United States 

Department of 

Agriculture

Animal and 

Plant Health 

Inspection 

Service

August 25,

2009

Rev. 10

Importation of Fruit of ‘Hass’ Avocado, 

Persea Americana, from Peru into the 

Continental United States

A Qualitative, Pathway-Initiated Risk Assessment

Agency Contact:

Plant Epidemiology and Risk Analysis Laboratory

Center for Plant Health Science and Technology

Plant Protection and Quarantine

Animal and Plant Health Inspection Service

United States Department of Agriculture

1730 Varsity Drive, Suite 300

Raleigh, NC 27606
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 ii

Executive Summary

This assessment examines the risks associated with the importation of  ̳Hass‘ avocado, Persea 

americana Miller., fruit from Peru into the United States. Among the pests found affecting 

avocado in Peru were six quarantine pests—five insects and one viroid—that may be associated 

with fresh avocado fruit from Peru as a pathway for introduction into the United States. These 

pests are as follows:

Insects

Anastrepha fraterculus Wiedemann (Diptera: Tephritidae)

Ceratitis capitata Wiedemann (Diptera: Tephritidae)

Coccus viridis (Green) (Hemiptera: Coccidae)

Ferrisia malvastra (McDaniel) (Hemiptera: Pseudococcidae)

Stenoma catenifer Walsingham (Lepidoptera: Oecophoridae) 

Viroid

Potato spindle tuber viroid

We qualitatively analyzed these quarantine pests using the methodology described in the USDAAPHIS Guidelines Ver. 5.02, which examines pest biology in the context of the Consequences of 

Introduction and Likelihood of Introduction, and estimates overall Pest Risk Potentials. Scale 

insects, Coccus viridis and Ferrisia malvastra, received Medium ratings for Pest Risk Potential.

Both fruit flies—Anastrepha fraterculus, and Ceratitis capitata—and the seed moth, Stenoma 

catenifer, were rated High risk. Although the viroid was rated High in the risk assessment, an 

additional analysis for the Likelihood of Establishment of the pathogen entering on avocados for 

consumption estimated the probability to be Low (Appendix B). Therefore, no mitigation 

measures are required against potato spindle tuber viroid. Specific phytosanitary measures may be 

necessary for pests with a baseline Pest Risk Potential of Medium. Port-of-entry inspections are 

insufficient to safeguard U.S. agriculture from pests that are rated High and mitigation measures 

are suggested to provide phytosanitary security.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 iii

Table of Contents

Executive Summary ....................................................................................................ii

1. Introduction.............................................................................................................1

2. Risk Assessment ......................................................................................................1

2.1. Initiating Event: Proposed Action.....................................................................................1

2.2. Assessment of Weediness Potential of Persea americana (avocado). ................................3

2.3. Previous Risk Assessments, Current Status, and Pest Interceptions...................................4

2.4. Pest List: Pests Associated with avocado in Peru ..............................................................4

2.5. Consequences of Introduction ........................................................................................20

2.6. Likelihood of Introduction..............................................................................................27

2.7. Conclusion: Pest Risk Potential and Phytosanitary Measures ..........................................30

3. Risk Mitigation......................................................................................................31

3.1. Prior to Harvest..............................................................................................................32

3.2. Post-harvest and Prior to Shipping .................................................................................33

3.3. During Shipping and at U.S. Ports-of-entry ....................................................................34

3.4. Monitoring .....................................................................................................................36

3.5. Conclusions....................................................................................................................36

4. Authors and Reviewers.........................................................................................38

5. Literature Cited ....................................................................................................38

6. Appendices.............................................................................................................50

Appendix A. Pest interceptions from selected countries in South America (excluding Peru) 

from the pest identification database..................................................................................50

Appendix B. Likelihood of Entry, Introduction, and Establishment of Potato Spindle Tuber 

Viroid (PSTVd) with Imported  ̳Hass‘ Avocado, Persea americana, Fruit from Peru........53
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 1

1. Introduction

The Animal and Plant Health Inspection Service (APHIS) of the United States Department of 

Agriculture (USDA) prepared this pest risk assessment to examine plant pest risks associated with 

the importation of fresh  ̳Hass‘ avocado, Persea americana fruits from Peru into the continental 

United States. This is a qualitative pest risk assessment. Estimates of risk are expressed in 

qualitative terms of high, medium, or low, rather than in numerical terms, such as probabilities or 

frequencies. The details of methodology and rating criteria are in the Guidelines for 

Pathway-Initiated Pest Risk Assessment, version 5.0 (PPQ, 2000).

International plant protection organizations, such as the North American Plant Protection 

Organization (NAPPO) and the International Plant Protection Convention (IPPC) provide 

guidance for conducting pest risk analyses. The methods used to initiate, conduct, and report this 

pest risk assessment are consistent with the guidelines provided by NAPPO and IPPC. The use of 

biological and phytosanitary terms conforms to the Glossary of Phytosanitary Terms (IPPC, 2007:

ISPM #5).

Avocado is part of the Lauraceae plant family, which has about 50 genera (Ploetz et al., 1994).

Most members of the family have aromatic foliage and include bays, camphor, cinnamon, and 

sassafras. Three races of avocado are generally recognized: Mexican, West Indian and 

Guatemalan; these races vary in their sensitivity to cold and fruit characteristics. Hass, of the 

Guatemalan race, is the leading variety produced in California. Hass has the advantages of year 

round production and excellent storage life and fruit quality. In 1987, Peru ranked 18th in annual 

production of avocado with 24,000 metric tons compared to Mexico‘s 357,000 metrics tons 

(Ploetz et al., 1994). Peruvian avocados for export are currently produced in Lima (20,180 Metric 

Tons in 1999), Ica (2,656) and Moquega (2,632) (Fig. 1, SENASA, 2002A).

2. Risk Assessment

2.1. Initiating Event: Proposed Action

This assessment was initiated in response to an official request for USDA authorization to allow 

imports under 7 CFR §319.56, the regulation which provides authority to USDA for restricting or 

prohibiting the importation of fruits and vegetables based on the risk of introducing harmful exotic 

plant pests into the United States. The PRA request was made by G.A. Ball, Import Specialist, 

Riverdale, MD, on October 31, 2001. Importing ―Hass‘ avocados (Persea americana) from Peru 

into the United States is a potential pathway for the introduction of pests. This pest risk 

assessment is commodity-based and therefore pathway-initiated.

2.1.1. Correspondence with Peru

December 29, 2000. Facsimile (2725) from Ing. Alicia de la Rosa Brachowicz, General 

Director Plant Health, SENASA to Dr Lou Vanechos, Area Director APHIS-IS, Chile. The 

letter included a request to export Persea americana fruit to the United States and contained 

the enclosed document ―The Phytosanitary Status of the avocado (Persea americana Miller) 

in Peru.‖
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 2

Figure 1. Avocado production in Peru (SENASA, 2002A).

January, 11, 2002. Facsimile from Robert V. Flanders, Risk Assessment Branch Chief, APHIS 

to Ing. Alicia de la Rosa Brachowicz, General Director Plant Health, SENASA to Dr Lou 

Vanechos, Area Director APHIS-IS, Chile. The letter indicated that APHIS has a backlog of 

PRAs. SENASA was offered the chance to conduct the PRA as a way to expedite the risk 

assessment process. 

January, 14, 2002. Letter from Ing. Alicia de la Rosa Brachowicz, General Director Plant 

Health, SENASA to Dr Lou Vanechos, Area Director APHIS-IS, Chile. It indicated that 

Annabella Reszcynski was compiling information on the cultivation of Avocado in Peru.

March 27, 2002. Letter from Alan S. Green (USDA/APHIS) to Dra. Elsa Carbonell Tores, 

SENASA. The letter acknowledged receipt of the report ―The Phytosanitary Status of the 

avocado (Persea americana Miller) in Peru.‖ The letter requested additional information 

relating to the harvest, packaging, shipment and export of avocados from Peru.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 3

June 14, 2002. Letter (1653-2002-AG-SENASA-DGSV-DDF) from Ing. Alicia de la Rosa 

Brachowicz, General Director Plant Health, SENASA to Dr Lou Vanechos, Area Director 

APHIS-IS, Chile. The letter listed helpful reference material for the PRA process.

July 11, 2002. Letter (1867-2002-AG-SENASA-DGSV-DDF) from Ing. Alicia de la Rosa 

Brachowicz, General Director Plant Health, SENASA to Dr Lou Vanechos, Area Director 

APHIS-IS, Chile. The letter provided the additional information requested by Alan S. Green 

on March, 27 2002.

June 17, 2003. Letter from Ing. Alicia de la Rosa Brachowicz, General Director Plant Health, 

SENASA to Dr Lou Vanechos, Area Director APHIS-IS, Chile. The letter indicated that only 

the ―Hass‖ variety of avocado should be considered for export. 

2.1.2. Documents Supplied by Peru

1. ―The Phytosanitary Status of the avocado (Persea americana Miller) in Peru.‖ December, 

2002. DGSV-DVF/DDF, 12 pp.

2. Information about the phytosanitary condition of the avocado (Persea americana Miller) In 

Peru. October, 2001

3. Draft proposal for the application of pest risk mitigation measures in the exportation of 

avocado (Persea americana) to the United States from Peruvian sites where the avocado seed 

moth (Stenoma catenifer) is not known to occur. SENASA, August, 2002.

4. ―Importation of avocado fruit (Persea Americana) from Peru. A Pest Risk Assessment.‖

SENASA, Dec 2002.

2.2. Assessment of Weediness Potential of Persea americana (avocado).

The weediness assessment is presented below (Table 1).

Table 1. Assessment of weediness potential of avocado

Phase 1: Persea americana is widely cultivated in California and Florida; (Ploetz et al., 1994; 

NRCS, 2003); avocadoes are also grown in Texas (Vines, 1960).

Phase 2: Is the species listed in:

NO Geographical Atlas of World Weeds (Holm et. al., 1979)

NO World's Worst Weeds (Holm et. al., 1977) or World Weeds: Natural 

Histories and Distribution (Holm et al., 1997)

NO Report of the Technical Committee to Evaluate Noxious Weeds; Exotic 

Weeds for Federal Noxious Weed Act (Gunn & Ritchie, 1982) 

NO Economically Important Foreign Weeds (Reed, 1977)

NO Weed Science Society of America list (WSSA, 2007)

NO Is there any literature reference indicating weediness (e.g., AGRICOLA, 

CAB, Biological Abstracts, AGRIS; search on "species name" combined 

with "weed").

Phase 3: Conclusion: Avocado is not considered to be an economically important weed. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 4

2.3. Previous Risk Assessments, Current Status, and Pest Interceptions

2.3.1. Decision History

For avocado fruit (limited to the last 30 years for South America) included one record: 1969 -

Peru, avocado: Entry was denied for lack of effective treatments for Ceratitis capitata, 

Anastrepha fraterculus, A. serpentina and Stenoma catenifer.

Avocado importation requests from other South American countries were denied in the following 

years due to lack of effective treatments for S. catenifer and/or Anastrepha sp.:

1961 - Columbia

1970 - Columbia

1974 - Brazil, Columbia

1977 - Chile

1991 - Argentina

1994 - Ecuador

2.3.2. Current status

USDA does not currently authorize the importation of avocado from South America except for 

from Chile (PPQ, 2004). Importation of avocado from Peru is currently not authorized. A list of

actionable and non-actionable pests (with the exception of non-reportable) intercepted on 

avocado from Peru is presented below (Table 2).

2.3.3. Pest interceptions

We listed pest interceptions on avocado for selected South American countries below (Appendix 

A). All interceptions were in baggage, quarters, and stores.

2.4. Pest List: Pests Associated with avocado in Peru

We listed the pests associated with avocado below (Table 3). The table was compiled from 

scientific and regulatory reports, including pest lists provided by Peruvian officials. For each pest, 

we summarize information on the presence or absence in the United States, commodity 

association (i.e., the generally attacked/infected plant parts), quarantine status in the United 

States, and the likelihood that the pest could move with the commodity in commerce (i.e. follow 

the pathway) (Table 3).

Organisms listed at the level of genus (or family), although regarded as quarantine pests because 

of their uncertain identity, are not further analyzed due to the lack of evidence of the risks that 

they pose (see discussion after the pest list).

Numerous pests included below are not subjected to further analyses because they are widely 

established in the United States; they are associated with plant parts other than the commodity; or 

they are associated with the commodity, but not likely to remain with the commodity due to 

various factors including processing.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 5

Table 2. Pest interceptions (recorded as events) on avocado, Persea americana, fruit from Peru, 

1985 to 2008 (PestID, 2008).

Pest Interceptions 

(no.)

Abgrallaspis sp. 1

Anastrepha sp. (Tephritidae) 2

Cladosporium sp. 1

Chrysomphalus pinnulifer (Diaspididae) 4

Curculionidae, species of 2

Diaspididae, species of 9

Fiorinia sp. (Diaspididae) 1

Heilipus sp. (Curculionidae) 2

Hemiberlesia diffinis 1

Oecophoridae, species of 2

Pentatomidae, species of 1

Phomopsis sp. 1

Phycitinae (Pyralidae)

Pinnaspis sp. (Diaspididae) 5

Pseudaonidia trilobitiformis (Diaspididae) 11

Pseudococcidae, species of 3

Sphaceloma sp. 1

Stenoma catenifer (Oecophoridae) 11

Total 58

Table 3. Pests reported on avocado in any country and present in Peru on any host.

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

ARTHROPODS

Acari: Tarsonemidae

Polyphagotarsonemus latus

Banks 

PE, US L, S, F, I No Yes CABI, 2002

Acari: Tetranychidae

Oligonychus mangiferus (Rahman 

and Sapra)

PE L Yes No Bolland et al., 1998; Hill, 

1983

 

1 Distribution: CA = California, FL= Florida, GA = Georgia, NY = New York, PE = Peru, USA = United States of America, TX 

= Texas.

2

Plant part affected: F = fruit, I = flower or inflorescence, L = leaves, S = stem, R = roots, Sd = seed, Pd = Pod, U = unknown

3 Quarantine Pest: U = Unknown. Brackets indicate that the species, although not fitting the definition of a quarantine pest (IPPC, 

2002), is considered actionable (APHIS, PPQ, National Identification Services)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 6

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Oligonychus peruvianus

(McGregor)

PE, US L No No Bolland et al., 1998; CABI, 

2003

Oligonychus punicae (Hirst) PE, US L No No Bolland et al., 1998; Hofshi, 

2005

Oligonychus yothersi (McGregor) PE, US L No No Bolland et al., 1998

Panonychus citrii (McGregor) PE, US L No No Bolland et al., 1998; Wolfe et 

al., 1969; Wysoki et al., 2002 

Tetranychus mexicanus

(McGregor)

PE, US L No No Bolland et al., 1998

Tetranychus neocaledonicus 

André

PE, US L No No Bolland et al., 1998

Tetranychus sp. PE L Yes No Alata Condor, 1973

Tetranychus urticae Koch PE, US L No No Bolland et al., 1998; Wolfe et 

al., 1969;

INSECTA

Coleoptera: Cerambycidae

Derobrachus asperatus Bates PE S Yes No Alata Condor, 1973; Hovore, 

2003

Oncideres poecilla Bates PE S Yes No Alata Condor, 1973; Wolfe et 

al., 1969; Wysocki et al., 2002

Oncideres sp. PE, US S Yes No Alata Condor, 1973; CABI, 

2003

Coleoptera: Curculionoidae

Copturomimus sp. L. PE S Yes No Alata Condor, 1973; Wysoki 

et al., 2002;

Heilipus empiricus (Pascoe) PE F, S4 Yes No5 Alata Condor, 1973; 

Heilipus sp. PE, US 

(FL)

F, Sd, R Yes No6Laurencao et al., 2003; Pena 

(2003); PestID, 2008; 

Wolfenbarger (1948)

Pantomorus cervinus Boheman PE, US L, F, S, R No Yes CABI, 2002

Rhynchophorus palmarum L. PE R, S, F

7

[Yes] No8 CABI, 2005

 

4 Based on biology of Heilipus catagraphus (Wysoki et al., 2002).

5 H. empiricus is only mentioned in the literature once by Alata Condor (1973). We found no other information about this species. 

According to SENASA (2005), this species is very rare in Peru and does not pose any economic threat. Heilipus sp. were 

intercepted twice on avocado in the passenger luggage from Peru (PestID, 2008), but this was insufficient evidence of its 

ability to follow the pathway. Thus, we did not further analyze this species. However, we reserve the right to add to the 

pathway any species of Heilipus if these insects are intercepted on avocados from Peru, because H. empiricus might be a 

misidentification by Alta Condor (1973) of some other species from the genus Heilipus.

6 We listed Heilipus sp. based on two interceptions in a passenger baggage, but that is not sufficient evidence to conclude that it 

will follow the pathway. However, as stated above, we reserve the right to add any species of Heilipus to the pathway in the 

future should they be intercepted in commercial avocados from Peru. Also, see Conclusion section for more information.

7

Predominantly a pest of palms; When reported on other plants, R. palmarum was feeding on ripe fruits but not causing 

economic damage (CABI, 2005). Avocado is a minor host of this species (CABI, 2005).

8

Eggs are usually inserted into previously damaged tissue (CABI, 2005), but only mature, unripe avocado fruits will be imported. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 7

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Coleoptera: Languriidae

Toramus sp. PE, US Sd, Pd No9 Yes Alata Condor, 1973

Coleoptera: Histeridae

Acritus sp. PE, US U No9 U Alata Condor, 1973; 

Anonymous, 2006a

Coleoptera: Nitulidae

Carpophilus sp. PE, US F No9 Yes Alata Condor, 1973

Coleoptera: Scarabeidae

Pelidnota chlorana Er. PE I, L Yes No Arellano Cruz, 1998

Coleoptera: Scolytidae

Pagiocerus frontalis Fabricus PE, US S No No Alata Condor, 1973

Diptera: Agromyzidae

Liriomyza trifolii Burgess in 

Comstock

PE, US L No No CABI, 2003; NZPPO, 1999

Diptera: Cecidomyiidae

Clinodiplosis sp. PE, US I, Sd, L No9 Yes Alata Condor, 1973

Diptera: Lonchaeidae

Neosilba pendula PE S, F Yes No10 Hofshi, 2005

Silba sp. PE S, F Yes6 No10 Alata Condor, 1973; CABI, 

2002; Katsoyannos, 1983

Diptera: Muscidae

Atherigona orientalis Schiner PE, US L, S, F No Yes CABI, 2002

Diptera: Tephritidae

Anastrepha fraterculus

Wiedemann 

PE F Yes Yes CABI, 2002; Norrbom 2004; 

Ovruski et al., 2003; Putruele, 

1996; White and Elson-Harris,

1992; Wille, 1952

Anastrepha serpentina

(Wiedemann)

PE F Yes No11 Bush, 1957; CABI, 2002

Ceratitis capitata Wiedemann PE F Yes Yes CABI, 2002; Hofshi, 2005; 

Liquido et al., 1990, 1998; 

Metcalf & Metcalf, 1993; 

Putruele , 1996; Snell, 2006; 

White & Elson-Harris, 1992 

 

Furthermore, this is a large insect—larvae reach up to 4-6 cm in length, and adults are 4-5 cm—that is likely to be noticed 

during packing.

9

Listed as  ̳Non-reportable‘ in Pest Identification database (PestID, 2008). Also, see Courneya (2003).

10 These species are secondary pests that attack hosts previously damaged by primary invaders, particularly fruit flies (McAlpine 

and Steyskal, 1982; White and Elson-Harris, 1992). Culling damaged fruit and mitigating against fruit flies is likely to remove

these pests from the pathway.

11 Avocado is a poor host for A. serpentina (Bush, 1957; Aluja et al., 2004). Therefore this pest is unlikely to follow the pathway.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 8

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Xanthaciura major Malloch PE, US I

12 No No Alata Condor, 1973; Morin et 

al., 1997; Peña and Bennett, 

1995

Hemiptera: Aetalionidae

Aetalion reticulatum L. PE F, S, I, L Yes No13 Alata Condor, 1973; Briceno, 

1977, Dominguez Gil, 1978

Hemiptera: Aleyrodidae

Aleurodicus cocois Curtis PE L Yes No Lopez and Kairo, 1999;

Seguenas and Camara, 2002;

Silva, 1978

Aleurodicus dispersus Russell PE, US 

(FL)

L [Yes]

14 No CABI, 2003

Aleurodicus pulvinatus (= A. 

ridescens)

PE L Yes No CABI, 2003

Hemiptera: Aphididae

Aphis gossypii (Glover) PE, US L, S, I No No Blackman & Eastop, 2000; 

CABI, 2003

Aphis spiraecola Patch PE, US L, S, I No No CABI, 2003

Myzus persicae Sulzer PE, US L, S No No CABI, 2002

Toxoptera aurantii Boyer de 

Fonscolombe

PE, US L, S, I No No Blackman and Eastop, 2000; 

CABI, 2003

Hemiptera: Coccidae

Ceroplastes cirripediformis 

Comstock

PE, US L, S No No Ebeling, 1959; Ben-Dov et al., 

2003

Ceroplastes floridensis Comstock PE, US L, S15 No No Ebeling, 1959; Ben-Dov et al., 

2003

Coccus hesperidum (L) PE, US L, S No No CABI, 2003; Ben-Dov et al., 

2003

Coccus viridis (Green) PE, US

(FL)

L, S, F [Yes]

16 Yes CABI, 2003; Courneya, 

2004b, 2006; Ben-Dov et al., 

2003

Parasaissetia nigra Nietner PE, US L, S No No CABI, 2002

Parthenolecanium corni (Bouché) PE, US L, S No No CABI, 2002; Swirski et al., 

1997

Protopulvinaria pyriformis

Cockerell 

PE, US 

(FL)

L, F, S No Yes Alata Condor, 1973; Ebeling, 

1959; Wysoki et al., 2002

Saissetia coffeae Walker PE, US L, S No No CABI, 2002

 

12 Based on biology of Xanthaciura connexionis (Morin et al., 1997).

13 This insect is an external pest and affects fruit at the early stages of development by causing fruit darkening or premature drop 

(Dominguez Gil, 1978). Damaged fruit are likely to be eliminated during culling.

14 Courneya (2004a)

15 Based on biology of C. cirripediformis

16 Courneya (2004b)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 9

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Saissetia oleae Oliver PE, US L, S No No CABI, 2002

Hemiptera: Diaspididae

Acutaspis sp. PE, US L, S, F Yes Yes Alata Condor, 1973; Peña et 

al., 2003

Acutaspis albopicta (Cockerell) PE, US 

(TX, CA)

L, F [Yes] Yes17 Courneya, 2005; Ben-Dov et 

al., 2003

Acutaspis subnigra McKenzie PE L Yes No Ben-Dov et al., 2003

Aspidiotus destructor PE, US L, F No Yes CABI, 2002; Miller and 

Davidson, 2005

Chrysomphalus aonidum (L.) PE, US L, S, F No Yes

Chrysomphalus dictyospermi

Morgan 

PE, US L, S, F No Yes CABI, 2003

Fiorinia fioriniae Targ. PE, US L, F No Yes Alata Condor, 1973; Wysoki 

et al., 2002

Hemiberlesia cyanophyilli 

Signoret [Syn. Abgrallaspis

cyanophylli (Signoret)]

PE, US L, S, F18 No Yes Alata Condor, 1973; CABI, 

2003

Hemiberlesia lataniae Signoret PE, US L, S, F No Yes CABI, 2002; Nakahara, 1982

Hemiberlesia palmae (Cockerell) PE, US 

(CA, FL)

L No No Ben-Dov et al., 2003

Hemiberlesia rapax (Comstock) PE, US L, S, F No Yes CABI, 2003; UCIPM, 2003

Howardia biclavis (Comstock) PE, US U No U Ben-Dov et al., 2003

Lopholeucaspis cockerelli

(Grandpré & Charmoy)

PE, US U No U Ben-Dov et al., 2003

Oceanaspidiotus spinosus 

(Comstock)

PE, US L, Bark No No Ben-Dov et al., 2003

Pinnaspis aspidistrae (Signoret) PE, US S, L, F No Yes SENASA, 2002c; Ben-Dov et 

al., 2003

Pinnaspis sp. PE, US S, L, F Yes Yes PestID, 2008

Pinnaspis strachani (Cooley) PE, US S, L, F No Yes Ben-Dov et al., 2003

Pseudaonidia trilobitiformis

Green 

PE, US 

(FL)

F

19, L [Yes] Yes17 Anon., 1979; Coile and 

Dixon, 2000; Cavey, 2007; 

PestID, 2008

Selenaspidus articulatus Morgan PE, US 

(CA)

L, S, F No Yes CABI, 2002; Miller and 

Davidson, 2005; Wolfe et al.,

1969; Wysoki et al., 2002

 

17 The armored scales A. albopicta and P. trilobitiformis may enter the United States on commercial fruit for consumption, but 

are unlikely to establish via this pathway. Please see discussion following the pest list for a detailed explanation.

18 Based on biology of Hemiberlesia lataniae (CABI, 2003).

19 This scale species has been intercepted on fruit at U.S. ports-of-entry (PestID, 2008).
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 10

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Unaspis citri Comstock PE, US L, F No Yes Alata Condor, 1973; Ben-Dov 

et al., 2003; Wolfe et al.,

1969; Wysoki et al., 2002

Hemiptera: Margarodidae

Icerya purchasi Maskell PE, US L, S No No CABI, 2003; Mendel et al., 

1992

Hemiptera: Membracidae

Tylopelta sp. PE S

20 Yes No Alata Condor, 1973

Hemiptera: Miridae

Dagbertus sp. PE, US L, I, F Yes No21 Leston, 1979; Pena, 2003; 

Yarita Rubinos, 2005

Hemiptera: Pentatomidae

Pentatomidae, species of PE, US L, F Yes No22 PestID, 2008

Hemiptera: Pseudococcidae

Dysmicoccus brevipes Cockerell PE. US L, S, R, F No Yes CABI, 2003

Ferrisia malvastra (McDaniel) PE, US 

(AZ, FL)

L, F, S23 [Yes] Yes Gullan et al., 2003; Miller et 

al., 2002; Ben-Dov et al., 

2003

Ferrisia virgata Cock PE, US L, F, S No Yes CABI, 2003

Nipaecoccus nipae Maskell PE, US L, S, F No Yes CABI, 2003

Planococcus citri (Risso) PE, US L, S, F, R No Yes CABI, 2003; 

Pseudococcus longispinus

Targioni 

PE, US S, F, L No Yes CABI, 2002

Hemiptera: Triozidae

Trioza perseae Tuthill PE L Yes No Alata Condor, 1973; Chavez 

et al., 1985; Hollis and 

Martin, 1997 

Hymenoptera: Formicidae

Acromyrmex hispidus Santaschi PE L Yes No Alata Condor, 1973; Arellano 

Cruz, 1998; San Juan, 2003

Atta cephalotes L. PE L Yes No Alata Condor, 1973; CABI, 

2003

Atta sexdens (L.) PE L Yes No Arellano Cruz, 1998; Ebeling, 

1959; Wolfe et al., 1969;

 

20 Based on biology of the family Membracidae.

21 Dagbertus sp. typically affects only young fruit, causing them to drop later, and prefers to oviposit on flowers (Pena, 2003). For 

these reasons, the pest is highly unlikely to follow the pathway. 

22 Because of its size, biology, and mobility, this pest is not expected to stay on the commodity through harvest, and standard 

handling and processing. Pentatomidae (species of) has only been intercepted 5 times, all in baggage (not cargo) and only once 

on fruit. This indicates that insects in this family are unlikely to follow commercial export quality fruit.

23 Based on biology of Ferrisia virgata.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 11

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Lepidoptera: Geometridae

Sabulodes caberata Gueneé PE, US 

(CA)

L No No Alata Condor, 1973; Condit, 

1915; Robinson et al.,, 2004; 

Wolfe et al., 1969; Wysocki et 

al., 2002

Lepidoptera: Gracilariidae

Phyllocnistis n. sp. PE, US 

(FL)

L Yes No CABI, 2002; Peña, 2003; 

Wolfe et al., 1969; Wysocki et 

al., 2002

Lepidoptera: Lymantriidae

Eloria sp. PE L, S Yes No Alata Condor, 1973; U.S. 

Congress, 1993 

Lepidoptera: Noctuidae

Chrysodeixis includens (Walker) 

[Syn. Pseudoplusia includens 

(Walker)]

PE, US L, F, I No No24 CABI, 2003

Helicoverpa zea (Boddie) PE, US L, I, F, Sd No Yes CABI, 2003; Robinson et al,

2004

Peridroma saucia Hübner PE, US L, S, F, I No No24 CABI, 2002

Spodoptera eridania Stoll PE, US L, F No No24 CABI, 2002

Lepidoptera: Oecophoridae

Stenoma catenifer Walsingham PE25 L, F, Sd Yes Yes Alata Condor, 1973, CABI, 

2002; Ebeling, 1959; Wolfe et 

al., 1969; Wysoki et al., 2002

Lepidoptera: Pyralidae

Jocara zetila Druce PE L Yes No Alata Condor, 1973; Arellano 

Cruz, 1998

Stericta albifasciata (Druce)

[Syn. Jocara ban Dyar]

PE L Yes No CABI, 2002; Ebeling, 1959 

Zhang, 1994

Lepidoptera: Psychidae

Oiketicus kirbyi Guilding PE L Yes No Alata Condor, 1973; Arce et 

al., 1987; Ponce et al., 1979; 

Rhainds et al., 1996

Lepidoptera: Sesiidae

Aegeria sp. PE, US S (trunk)26 Yes No Alata Condor, 1973; BFW, 

2004; Zhang, 1994

Lepidoptera: Tortricidae

Platynota sp. PE, US L Yes No Alata Condor, 1973

 

24 External feeder; damaged fruits are likely to be eliminated from packing by visual culling.

25 The pest has a limited distribution in Peru (CABI, 2005).

26 We based this information on that for Sesia sp. of the same family, Sesiidae. Larvae of this family are generally stem borers.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 12

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Thysanoptera: Thripidae

Heliothrips haemorrhoidalis

Bouche 

PE, US L, F No Yes CABI, 2002

Selenothrips rubrocinctus Giard PE, US L, F No Yes CABI, 2002

VIRUSES

Avocado sunblotch viroid PE, US 

(CA, FL)

L, F, S, I No Yes Ploetz, et al., 1994, Vargas, et 

al. 1991

Potato spindle tuber viroid PE L, F, S, I Yes27 Yes CABI 2003; Querci, et al.

1995 

ALGAE

Cephaleuros viriscens Künze

(Trentepohliales, 

Trentepohliaceae)

PE, US

(FL)

L, S No28 No Alfieri et al., 1993; Bazán de 

Segura, 1959; Brannen, 2004

BACTERIA

Rhizobium radiobacter

(Beijerinck & van Delden 1902) 

Young (Rhizobiaceae, 

Rhizobiales)

PE, US R, S No No CABI, 2002

FUNGI and CHROMISTANS

Armillaria sp.

29 (Agaricales, 

Marasmiaceae)

PE R, S Yes No CABI 2003; Gonzalez and 

Abad, 1975; Wellman, 1977

Aspergillus niger Tiegh. 

(Anamorphic Emericella, 

Eurotiales, Trichocomaceae.)

PE, US F, L, R, S, I No Yes CABI 2003; Torres and 

Gamarra, 1988; Wellman, 

1977

Botryodiplodia sp. (Anamorphic 

Ascomycetes)

PE, US F, I, L, S No Yes Farr et al., 2004; Torres and 

Gamarra, 1988

Botryosphaeria dothidea (Moug.) 

Ces. & de Not. (=Physolospora 

perseae Doidge). (Anamorph: 

Fusicoccum sp. Dothideales, 

Botryosphaeriaceae.)

PE, US F, L, S30 No Yes Bazán de Segura, 1959; CABI 

2003; Farr et al., 2004, Kirk, 

et al. , 2001b; Ploetz et al., 

1994.

Botrytis cinerea Pers.: Fr

(Anamorphic Helotiales, 

Sclerotiniaceae) 

PE, US L, S, I, F, 

Sd

No Yes CABI 2003; Wellman, 1977

 

27 Potato Spindle Tuber Viroid was declared absent from the United States (NAPPO, 2004a).

28 Listed as non-reportable (PestID, 2008).

29 Reported as Armillaria mellea. As currently accepted, A. mellea is a northern hemisphere species except for a single 

introduction into South Africa (Coetzee et al. 2001). Reports of its occurrence in South America are likely to be errors. A 

recent study (Coetzee and Wingfield 2003) identified A. luteobubalina and A. novae-zelandiae from Chile and Argentina. 

Both of these species occur in Australia and New Zealand, but not in the United States. It is uncertain which species of 

Armillaria was detected in Peru, therefore the quarantine status is ―Yes.‖

30 We based these associations on the biology of P. pyricola Nose (Botryosphaeria berengeriana f.sp. pyricola).
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 13

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Ceratocystis fimbriata Ellis & 

Halst (Microascales, 

Ceratocystidaceae)

PE, US F, L, R, S No28 No31 CABI 2003; Farr et al., 2004;

Cercospora lingue Speg. 

(Anamorphic 

Mycosphaerellales, 

Mycosphaerellaceae)

PE L, F No32 Yes Farr et al., 2004; Wellman, 

1977

Cercospora perseae33Ell. & Mart. 

(Anamorphic 

Mycosphaerellales, 

Mycosphaerellaceae)

PE, US L, F No Yes Farr et al., 2004; Palm, pers. 

com. 2005; Wellman, 1977

Cladosporium sp. (Anamorphic

Mycosphaerellales,

Mycosphaerellaceae)

PE R, S, F Yes Yes CABI, 2003; PestID, 2008

Corticium salmonicolor Berk. & 

Broome. (=Erythricium 

salmonicolor (Berk. & 

Broome) Burd. Polyporales, 

Phanerochaetaceae)

PE, US L, S No No CABI 2003; Farr et al., 2004; 

Wellman, 1977

Curvularia lunata (Wakk.) 

Boedijn. (= Acrothecium 

lunatum Wakk. Teleomorph:

Cochliobolus lunatus R.R. 

Nelson & Haasis. Pleosporales, 

Pleosporaceae)

PE, US L No No CABI 2003; Wellman, 1977

Fusarium lateritium Nees. 

(Teleomorph Gibberella 

baccata (Wallr.) Sacc.

Hypocreales, Nectriaceae)

PE, US F, R, S, I, No Yes CABI 2003; Icochea et al., 

1994; Wellman, 1977

Fusarium roseum Link.

(Teleomorph Gibberella zea

(Schwein.) Petch. Hypocreales, 

Nectriaceae)

PE, US F, R, S, L No Yes CABI 2003; Icochea et al., 

1994; Wellman, 1977

 

31 Ceratocystis fimbriata typically only causes stem and trunk cankers of its hosts but has been reported to cause superficial 

lesions on cocoa pods (CABI, 2005). The fungus produces sticky spores that are splash dispersed (Hodges, 2006) or moved by 

insects and pruning tools (CABI, 2005). Fruit infections of avocado have not been documented and the skin of the avocado, if it

could be contaminated with the sticky spores, is highly unlikely to contact a fresh wound in a host plant in the United States. 

Ceratocystis fimbriata has not been intercepted at U.S. ports-of-entry on any commodity from any country (1985 to 

September, 2008; PestID, 2008). Standard post-harvest treatments and processing such as cleaning from dirt and dust and 

washing in low concentration of a bleach solution (see Risk Mitigation section: post-harvest procedures in the packing house) 

are likely to eliminate any spores from the surface.

32 Cercospora lingue is listed in Wellman, 1977, but is not a recognized Cercospora fide (Chupp, 1953) and its status is unclear 

(Crous and Braun, 2003). Consequently, we did not further analyze it.

33 Cercospora persae and C. purpurea are sometimes found together on the same leaf, however they are morphologically distinct 

species (Chupp, 1953).
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 14

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Fusarium oxysporum Schlecht.

(Anamorphic Gibberella. 

Hypocreales, Nectriaceae)

PE, US F, R, S, L No Yes CABI 2003; Icochea et al., 

1994; Wellman, 1977

Fusarium solani (Martius) Sacc.

(Teleomorph Nectria 

haematococca (Wollenw.) 

Gerlach. Hypocreales, 

Nectriaceae)

PE, US S, R No No CABI 2003; Farr et al., 2004

Gibberella avenacea R.J. Cook

(Anamorph Fusarium 

avenaceum (Fr.) Sacc.

Hypocreales, Nectriaceae.)

PE, US F, I, L, S No Yes CABI, 2002

Glomerella cingulata (Stonem.) 

Spauld. & Schrenk (Incertae 

sedis, Glomerellaceae)

PE, US F, L, S, I, 

Sd

No Yes CABI 2003; Farr et al., 2004

Lasiodiplodia theobromae (Pat.) 

Griffiths & Maubl. (anamorphic 

Botryosphaeriaceae)

PE, US F, I, L, S No Yes CABI 2003; Bazán de Segura, 

1959

Macrophomina phaseolina

(Tassi) Goid (Anamorphic 

Ascomycetes)

PE, US F, I, L, R, S,

Sd

No Yes CABI 2003; Farr et al., 2004

Mucor sp. (Mucorales, 

Mucoraceae) 

PE L, F Yes Yes Arce et al., 1974; Wellman, 

1977

Mycena citricolor (Berk. & 

Curtis) Sacc. (Anamorph 

Stilbella flavidum (Cooke) 

Henn. Agaricales, 

Tricholomataceae).

PE, US

(FL)34

L, F, S Yes34 No35 CABI, 2002; Wellman, 1977

Nectria rigidiuscula Berk. & 

Broome. (Anamorph Fusarium 

rigidiusculum W.B. Snyder & 

H.P. Hansen. Hypocreales, 

Nectriaceae)

PE, US S, F No Yes CABI, 2002

 

34 Mycena citricolor is reported as present in Florida (CABI, 2002). However, Florida experts indicate that it has not been 

detected there since 1926 (Schubert, 2002).

35 Mycena citricolor seems unlikely to follow the pathway, as we found no reference that it specifically attacks avocado fruit. For 

example, Mariau (2001) and Wellman (1977) report M. citricolor infects the fruit of coffee, but do not report that it infects

avocado fruit. Most references refer to M. citricolor as a pest of coffee (Mariau, 2001; CABI, 2004; Thurston, 1989; Wellman, 

1977). Avocado is not listed as any kind of host in CABI (2004). On coffee, the disease produces sub-circular spots on leaves,

initially brown becoming pale-brown to straw-colored. Similar spots may be produced on stalks and berries. The main effect is 

to cause leaf fall with a consequent reduction in growth and yield of the coffee tree (CABI, 2004). Although it has been 

reported in Peru (Farr et al., 2004; CABI, 2004), it has not been intercepted on avocado fruit or any fruit from any country 

since at least 1985, the earliest APHIS computerized interception data available (PestID, 2008). Because M. citricolor is 

primarily a leaf spotting disease, primarily a disease of coffee (Coffea spp.), and has neither been reported on nor intercepted 

on avocado fruit, we did not consider it likely to follow the pathway.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 15

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Nigrospora oryzae (Berk. & 

Broome) Petch. Teleomorph 

Khuskia oryzae H.J. Huds..

Trichosphaeriales, Taxonomic 

position of family uncertain.

PE, US L, F No Yes CABI, 2002; Vallejos and 

Mattos, 1990; Wellman, 1977

Oidium sp. (powdery mildew) 

(Anamorphic Erysiphales, 

Erysiphaceae) 

PE L Yes No Alfieri, 1984; Bazán de 

Segura, 1959; 

Pellicularia koleroga Cooke

(=Corticium koleroga (Cooke) 

Höhn. Ceratobasidiales, 

Ceratobasidiaceae)

PE, US S, L No No CABI, 2002; Wellman, 1977

Pestalotiopsis guepinii (Desm.) 

Steyaert. (=Pestalotia guepinii

Desm. Anamorphic 

Pestalosphaeria. Xylariales, 

Amphisphaeriaceae).

PE, US L, F No Yes Alfieri, 1984; Bazán de 

Segura, 1959

Pestalotia leprogena Speg.

(Anamorphic Broomella.

Xylariales, 

Amphisphaeriaceae).

PE, US L No No Farr et al., 2004; Wellman, 

1977

Pestalotiopsis neglecta (Thüm.) 

Stayaert . (=Pestalotia neglecta

Thüm). Anamorphic 

Pestalosphaeria. Xylariales, 

Amphisphaeriaceae)

PE, US L, S, F No Yes Farr et al., 2004; Wellman, 

1977

Phomopsis sp. (Anamorphic 

Diaporthe. Diaporthales, 

Valsaceae)

PE F, S Yes Yes Alfieri, 1984; PestID, 2008

Phytophthora cactorum (Lebert &

Cohn) J. Schröt. (Pythiales, 

Pythiaceae) 

PE, US L, S, F, R No Yes CABI, 2003

Phytophthora cinnamomi Rands.

Pythiales, Pythiaceae

PE, US L, S, R No No Bazán de Segura, 1959; 

CABI, 2002; Ploetz, et al., 

1994

Phytophthora citrophthora (R.H. 

Sm. & E. Sm.) Leonian.

(Pythiales, Pythiaceae)

PE, US F, L, R, S, 

Sd

No Yes CABI, 2003; Farr et al., 2004

Phytophthora nicotianae Breda 

de Haan var. parasitica

(Dastur) G.M. Waterhouse

(Pythiales, Pythiaceae)

PE, US L, S, F, R No Yes Alfieri, et al., 1984; Farr, et 

al., 1989; CMI, 1964; CABI, 

2003

Phytophthora palmivora (E. J. 

Butler) E. J. Butler (Pythiales, 

Pythiaceae)

PE, US L, S, F, R, I No Yes CABI, 2003; Wellman, 1977
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 16

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

Polyporus hirsutus (Wulfen) Fr.

(Polyporales, Polyporaceae)

PE, US S No No Farr et al., 2004; Wellman, 

1977

Pseudocercospora purpurea

(Cooke) Deighton (= 

Cercospora purpurea Cooke).

Anamorphic Mycosphaerellales, 

Mycosphaerellaceae.

PE, US F, L No Yes Bazán de Segura, 1959; CABI 

2003; Farr et al., 2004; Ploetz 

et al. 1994; Wellman, 1977

Pycnoporus sanguineus (L.) 

Murrill (=Polyporus 

sanguineus (L.) Fr.

Polyporales, Polyporaceae.)

PE, US S No No Farr et al., 2004; Renjifo and 

Trujillo, 1992

Pythium ultimum Trow (Pythiales, 

Pythiaceae)

PE, US R No No CABI, 2003; Perez et al., 

1994; Wellman, 1977

Rhizoctonia solani Kühn.

(Teleomorph Thanatephorus 

cucumeris (Frank) Donk.

Ceratobasidiales, 

Ceratobasidiaceae)

PE, US L, S, F, R, I,

Sd

No Yes CABI, 2003; Farr et al., 2004; 

Wellman, 1977

Rhizoctonia sp. (Anamorphic 

Ceratobasidiales, 

Ceratobasidiaceae)

PE L, S, F, R, I,

Sd

Yes Yes Perez, 1999; Wellman, 1977

Rigidoporus microporus (Sw.) 

Overeem. Polyporales, 

Meripilaceae.

PE, US R, S No No CABI, 2003; Farr et al., 2004

Rosellinia bunodes (Berk. & Br.) 

Sacc. Xylariales, Xylariaceae.

PE R, S Yes No Menge and Ploetz, 2003; 

Ploetz, et al., 1994; Watson, 

1971; CMI, 1985, CABI 

2003; Farr et al., 2004

Sclerotinia sclerotiorum (Lib.) de 

Bary (Helotiales, 

Sclerotiniaceae)

PE, US L, S, F, I, R No Yes CABI, 2002

Sclerotium rolfsii Sacc.

(Teleomorph Athelia rolfsii

(Curzi) C.C. Tu & Kimbr.

Polyporales, Atheliaceae)

PE, US L, S, F, R, I,

Sd

No Yes CABI, 2003; Wellman, 1977

Sphaceloma perseae Jenk. 

Anamorphic Elsinöe.

Myriangiales, Elsinoaceae.

PE, US 

(FL, TX)

F, I, L No Yes Alfieri, et al., 1984; CABI, 

2002; Farr et al., 2004; 

Pernexny, 2000.

Sphaeropsis tumefaciens Hedges.

(Anamorphic Ascomycetes.)

PE, US 

(FL)

S No28 No CABI, 2003; Timmer, 2003

Verticillium dahliae Kleb.

(Anamorphic Hypomyces.

Hypocreales, Hypocreaceae)

PE, US L, S, F, R, I,

Sd

No Yes CABI, 2003; Farr et al., 2004;
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 17

Scientific Name, Classification Distribution1Plant part 

affected2

Quarantine pest3Follow

pathway3

References 

NEMATODES

Tylenchida: Belonolaimidae

Tylenchorhynchus sp. PE R Yes No Torres, 1977; Wellman, 1977

Tylenchida: Hoplolaimidae

Helicotylenchus dihystera (Cobb) 

Sher

PE, US R No No CABI, 2003

Helicotylenchus multicinctus

(Cobb) Golden

PE, US R No No CABI, 2003

Helicotylenchus sp. PE R No No Torres, 1977; Wellman, 1977

Rotylenchulus reniformis Linford 

& Oliveira 

PE, US R No No CABI, 2003

Tylenchida: Heteroderidae

Meloidogyne sp. PE R Yes No Delgado and Rosas, 1977; 

Wellman, 1977

Tylenchida: Pratylenchidae

Pratylenchus brachyurus

(Godfrey) Filipjev & 

Schuurmans Stekhoven

PE, US R, S No No CABI, 2003

Radopholus similis (Cobb) 

Thorne

PE, US R, S No No Anonymous, 1984; 

Anonymous, 1992; CABI, 

2003; PestID, 2008; Ploetz, et 

al., 1994

Dorylaimida: Xiphinematidae

Xiphinema floridae Lamberti & 

Bleve-Zecheo

PE, US 

(FL)

R No No Lamberti, et al. 1987; 

Lehman, 2002

MOLLUSCA

Helix aspersa Muller [=Sy. Cornu 

aspersum (Muller)]

PE, US L, S, R, F, 

Sd

No36 No37 CABI, 2003

 

36 Action required to PR, FL, and AL (Courneya, 2004a).

37 This large pest is unlikely to stay on the commodity through harvest and standard handling and processing.

Table 4. Quarantine Pests Likely to be Associated with avocado imported from Peru

Type Pests Taxonomy

Arthropods Anastrepha fraterculus Wiedemann Diptera: Tephritidae

Ceratitis capitata Wiedemann Diptera: Tephritidae

Coccus viridis (Green) Hemiptera: Coccidae

Ferrisia malvastra (McDaniel) Hemiptera: Pseudococcidae

Stenoma catenifer Walsingham Lepidoptera: Oecophoridae

Viroid Potato spindle tuber viroid
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 18

2.4.1. General discussion

We listed the quarantine pests selected for further analysis above (Table 4). We only analyzed 

further those quarantine pests that can be reasonably expected to follow the pathway of 

commercial shipments of export avocado fruit. Other quarantine pests not included in this 

summary could be detrimental to U.S. agriculture, but were not further analyzed for a variety of 

reasons, as follows: the pest‘s primary association is with plant parts other than the commodity, 

such as Aleurodicus cocois, Aleurodicus pulvinatus, Oligonychus mangiferus, Oncideres 

poecilla, Trioza perseae, etc., which are associated with leaf or stem feeding (Bolland et al., 

1998; CABI, 2003; Hollis and Martin, 1997; Lopez and Kairo, 1999); pests may be intercepted 

during inspection by Agricultural Officers as biological contaminants of the commodity (PestID, 

2008), but biological contaminants are not expected to be present in every shipment.

Also, the biological hazard of organisms identified to the order, family or generic levels was not 

assessed; however, if pests identified to higher taxa are intercepted in the future, then a

reevaluation of their risk may occur. In this risk assessment, this applies to the arthropods 

Acutaspis sp. and Pinnaspis sp., and the pathogens Phomopsis sp., Cladosporium sp., and

Oidium sp. Generally, the biological hazard of organisms not identified to the species level is not 

assessed because there are many species within a genus, and it is not reasonable to assume that 

the biology of all organisms within a genus is identical. The lack of species‘ identification may 

indicate the limits of the current taxonomic knowledge, the life stage, or the quality of the 

specimen submitted for identification. By necessity, pest risk assessments focus on the organisms 

for which biological information is available. The lack of identification at a specific level does not 

rule out the possibility that a high risk quarantine pest was intercepted or that the intercepted pest 

was not a quarantine pest. Conversely, development of detailed assessments for known pests that 

inhabit a variety of ecological niches, such as the surfaces and/or interiors of fruit, stems or roots, 

allow effective mitigation measures to eliminate the known organisms, as well as similar, but 

incompletely identified organisms that inhabit the same niche.

Other plant pests listed in Table 3 that were not chosen for further scrutiny may be potentially 

detrimental to the agricultural systems of the United States; however, there were a variety of 

reasons for not subjecting them to further analysis.

2.4.2. Anastrepha species discussion

In the past, Anastrepha species were one of the greatest concerns in allowing the importation of 

Mexican avocados. A review of the current literature, however, suggests that under most 

circumstances, Hass avocados do not serve as hosts for Anastrepha spp., as indicated by recent 

laboratory and field (Aluja et al. 2004) tests conducted in Mexico. The research prompted a reevaluation of the potential of Anastrepha spp. to infest Hass avocado in Mexico. The reevaluation concluded that uninjured, commercially produced Hass avocados in Mexico do not 

serve as hosts for the Anastrepha ludens, A. serpentina, and A. obliqua. Nevertheless, the current 

re-evaluation of  ̳Anastrepha sp. - Hass avocado‘ relationships is based on experiments conducted 

in Mexico only, and, therefore, should be extrapolated to other regions of the world with caution, 

considering that Norrbom (2004) lists a field study by Wille (1952) that shows avocado is a host 

for some of the species in Peru. In addition, the Mexican studies indicated that Hass avocado 

could possibly be a host for species of Anastrepha under some environmental or tree stress 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 19

circumstances (Aluja et al. 2004). Anastrepha fraterculus is variable in its pest status in different 

regions, and isozyme and karyotype studies suggest that what has been considered fraterculus

consists of several closely similar ―sibling species‖ (Foote et al., 1993 and references therein).

This species complex has not yet been studied in sufficient detail to permit a clear separation of 

the included species (White and Elson-Harris, 1992): thus, in Venezuela, Andean and lowland 

populations are distinct species, and populations from southern and north-eastern Brazil also have 

marked genetic differences. Also, ―there is evidence that the Mexican morphotype differs 

significantly from South American morphotypes‖ (Aluja et al., 2004 and references therein) and 

this was one of the reasons why A. fraterculus was not investigated in Mexico by Aluja et al. 

(2004). Reliable research is very limited regarding actual host status of avocado for several 

Anastrepha species in different parts of the Western Hemisphere which leads to a high uncertainty 

level. Given available evidence, we believe that A. fraterculus could be considered a pest of 

avocado in Peru (Jiron et al., 1988; White and Elson-Harris, 1992; Uchôa et al., 2002) while A. 

obliqua and A. serpentina are less likely to infest avocados (Bush, 1957; Uramoto et al., 2001;

Norrbom, 2004; Aluja et al., 2004).

Two species of Anastrepha had dubious records of a host association with avocado. Anastrepha

striata only occasionally infests avocado in the field in Costa Rica and Brazil (Jiron et al., 1988; 

Uchôa et al., 2002). Likewise, for A. obliqua, only one record of a host relationship exists, from

Brazil, where three females were ―recovered from host fruit‖ of unspecified numbers and of 

unknown variety (Uramoto et al., 2001), and Norrbom (2004) reported that avocado is not a 

natural host for A. obliqua. Most importantly, recent trials in Mexico definitively established that 

avocado is not a host of either A. obliqua or A. striata (Aluja et al. 2004). 

Considering genetic diversity of A. fraterculus, more data on the suitability of Hass avocado as a 

host should be collected in Peru. This would be based on results of adult fly trappings in avocado 

groves, fruit cuttings for possible larval infestations, as well as further experiments designed to 

actually identify their status as pests of avocado.

2.4.3. Armored scales discussion

In the draft pest risk assessment for Hass avocados imported from Peru that was made available 

to the public for comment on May 25, 2006, we listed Acutapsis albopicta and Pseudaonidia 

trilobitiformis as quarantine pests and analyzed the risk associated with them. In this revised risk 

assessment however, these armored scales are not further analyzed because, although they may 

enter on commercial fruit for consumption, armored scales are not expected to become 

established, and therefore introduced, via this pathway (Miller, 1985; PERAL, 2007). A recent 

review of the literature, APHIS-PPQ operational data, and expert opinion concludes that, even 

assuming high quantities of imported fruit infested with armored scale species that could be 

parthenogenic, highly fecund, polyphagous, invasive, theoretically able to survive in most of the 

United States, and cause high level consequences, the specific pathway represented by 

commercially produced fruit shipped without leaves, stems or contaminants constitutes an 

extremely low risk (PERAL, 2007). This low risk is explained by poor ability of armored scales to 

disperse to new host plants from fruits for consumption, and consequently, by their low 

probability of establishment (PERAL, 2007). The following characteristics of armored scales 

contribute to their poor dispersal capabilities:
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 20

Legs and wings are absent in females and in feeding immature forms. Males possess wings but 

are short-lived, do not feed, and tend to mate with nearby females.

Self-dispersal of armored scales occurs by immature forms, or ―crawlers‖. They are the most 

vulnerable life stage, survival of which decreases with long distance wind dispersal. Crawlers 

can be passively dispersed by wind from one plant to another only during a time period of 

approximately 24 hours. No further dispersal is possible after the crawlers start feeding as they

lose their legs during the first molt and the mouth parts are deeply inserted in the host, 

anchoring them firmly to the substrate.

Dispersal from fruit discarded in the environment is considered very unlikely because of low 

wind speeds at ground level and low survival rate of crawlers on the ground or on decaying 

fruit or fruit peel. There is a low probability of active dispersal of crawlers by walking from 

their natal host since they are not capable of rapid movement over bare soil or rough surfaces.

An additional reason for not analyzing the armored scales in this risk assessment is that 

commercially produced avocado fruit is expected to have a low infestation rate of armored scales 

due to requirements of industry quality standards. Processing, culling, and inspection of fruit 

infested with armored scales can further reduce the prevalence and survival of this group of pests.

2.5. Consequences of Introduction

The undesirable consequences that may occur from the introduction of quarantine pests is

assessed in this section. For each quarantine pest, the potential Consequences of Introduction are 

rated in five areas called ―Risk Elements‖: climate-host interaction, host range, dispersal potential, 

economic impact and environmental impact. The ratings are determined using the criteria in the 

risk assessment Guidelines, Version 5.02 (PPQ, 2000). A cumulative risk rating is then calculated 

by summing the values; we summarized these ratings below (Table 5).

The major sources of uncertainty present in this risk assessment are similar to those in other risk 

assessments: the use of a developing process (PPQ, 2000; Orr, et al., 1993), the approach used to 

combine risk elements (Bier, 1999; Morgan and Henrion, 1990), and the evaluation of risk by 

comparisons to lists of factors within the guidelines (Kaplan, 1992; Orr et al., 1993). To address 

this last source of uncertainty, the lists of factors are interpreted as illustrative and not exhaustive.

Another traditionally recognized source of uncertainty is the quality of the biological information 

(Gallegos and Bonano, 1993), which includes uncertainty whenever biological information is 

lacking on the regional flora and fauna. Inherent biological variation within a population of 

organisms also introduces uncertainty (Morgan and Henrion, 1990).

Anastrepha fraterculus Wiedemann (Diptera: Tephritidae) Risk ratings

Risk Element #1: Climate-Host Interaction

The A. fraterculus species complex is widely distributed in Central and South 

America, with restricted distribution in Mexico (CAB, 2001a; Weems, 2002).

This group occurs from the south of Texas to Argentina (Foote et al., 1993). A 

conservative estimate is that this insect can survive in Plant Hardiness Zones 7-10 

of the Continental United States (USDA-NA, 2003).

High (3)

Risk Element #2: Host Range High (3)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 21

Anastrepha fraterculus Wiedemann (Diptera: Tephritidae) Risk ratings

Anastrepha fraterculus is extremely polyphagous. Preferred hosts include 

Myrtaceae, Eugenia and Syzygium spp.and guava. Other hosts of this species are 

Terminalia catappa (Combretaceae), Malus pumila and Prunus spp. (Rosaceae), 

Annona spp. (Annonaceae), Citrus spp. (Rutaceae), Coffea spp. (Rubiaceae), 

Ficus carica (Moraceae), Juglans spp. (Juglandaceae), Diospyros kaki

(Ebenaceae), Manilkara zapota (Sapotaceae), Persea americana (Lauraceae), 

Solanum quitoense (Solanaceae), Theobroma cacao (Sterculiaceae), Olea 

europaea (Oleaceae), and Vitis vinifera (Vitaceae) (CABI, 2003); Passiflora spp. 

(Passifloraceae) (Aguiar-Menezes et al., 2002).

Risk Element #3: Dispersal Potential

Females deposit 200-400 eggs in host fruits (White & Elson-Harris, 1992). 

Reproduction is continuous, as adults are present year-round (CABI, 2003). In 

international trade, the major means of dispersal to previously un-infested areas is 

the transport of fruit containing larvae. For most regions, the most important 

fruits liable to carry this species are mango and guava (CABI, 2003).

High (3)

Risk Element #4: Economic Impact

Anastrepha fraterculus is the most economically important Anastrepha in Brazil 

and other South American countries because of its broad host range (Foote et al., 

1993). In Brazil, where it causes severe yield losses in apple, the pest is of major 

concern to growers, and represents a significant constraint to fresh fruit export 

into countries with quarantine barriers (Sugayama et al., 1996). The insect is also 

an important pest of guava and mango, and to some extent Citrus and Prunus

spp. (CABI, 2003). Introduction and establishment of this fruit fly will increase 

cost of production due to application of pesticides and initiation of monitoring 

programs. Anastrepha fraterculus is an important pest of quarantine significance 

and its establishment will lead to losses of foreign and domestic markets. 

High (3)

Risk Element #5: Environmental Impact

The extreme polyphagy of this species predisposes it to attack plants in the United 

States listed as Threatened or Endangered, such as Prunus (P. geniculata, FL)

(USFWS, 2004). Its wider establishment in the United States would likely lead to 

the initiation of chemical or biological control programs.

High (3)

Ceratitis capitata (Diptera: Tephritidae) Risk ratings

Risk Element #1: Climate-Host Interaction

Ceratitis capitata is found in Southern Europe and West Asia, throughout Africa, 

South and Central America, and in Northern Australia (CABI, 2002). We estimate

this species could establish within Plant Hardiness Zones 7-10 of the continental 

United States (USDA-NA, 2003).

High (3)

Risk Element #2: Host Range 

This pest has been recorded on a wide variety of host plants in several families, 

including Rubiaceae (Coffea spp.), Solanaceae (Capsicum annuum), Rutaceae 

(Citrus spp.), Rosaceae (Malus pumila, Prunus spp), Moraceae (Ficus carica), 

High (3)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 22

Ceratitis capitata (Diptera: Tephritidae) Risk ratings

Myrtaceae (Psidium guajava), Sterculiaceae (Theobroma cacao), Arecaceae 

(Phoenix dactylifera) and Anacardiaceae (Mangifera indica) (CABI, 2002), 

Lauraceae (Persea americana) (Putruele, 1996).

Risk Element #3: Dispersal Potential

Eggs are deposited in host fruit in small batches of six to eight (Hassan, 1977), 

around 300 per female (Weems, 1981). In warm climates breeding is continuous 

throughout the year, as there are several overlapping generations (Hassan, 1977). 

Adults can fly 20 or more kilometers (CABI, 2002). Transport of infested fruits is 

the major means of movement and dispersal to previously un-infested areas 

(CABI, 2002).

High (3)

Risk Element #4: Economic Impact

Ceratitis capitata is an important pest in Africa, and can be spread in suitable 

climates worldwide, making it the single most important pest species in its family 

(CABI, 2005). In Mediterranean countries, the pest is particularly damaging to 

citrus and peach crops increasing cost of production due to expenses related to 

control programs. It may also transmit fruit-rotting fungi (CABI, 2005). Ceratitis 

capitata is of quarantine significance worldwide, especially for Japan and the 

United States, where we spent considerable resources in order to prevent 

introduction of this fly (CABI, 2005). Its presence can lead to severe constraints 

for fruit export leading to losses of foreign and domestic markets (CABI, 2005).

High (3)

Risk Element #5: Environmental Impact

The introduction and establishment of C. capitata in the United States will trigger 

the initiation of chemical control, particularly bait sprays. The species is highly 

polyphagous, and can attack the following species listed as Threatened or 

Endangered: Prunus geniculata (FL); Argemone pleiacantha (NM); Asimina

tetramera (FL); Berberis nevivii, B. pinnata, B. sonnei, (CA); Cucurbita

okeechobeensis (FL); Echinocereus chisoensis, E. reichenbachii, E. iridiflorus

(TX); E. fendleri (NM); E. triglochidiatus (AZ); Euphorbia telephioides (FL);

Opuntia treleasei (CA); Ribes echinellum (FL, SC); and Ziziphus celata (FL)

(USFWS, 2006). As species of Opuntia are hosts, damage can disrupt critical 

habitats in the Southwest (Chavez-Ramirez et al., 1997).

High (3)

Coccus viridis (Green) (Hemiptera: Coccidae) Risk ratings

Risk Element #1: Climate-Host Interaction

This species is pantropical in distribution. It has been reported from India through 

Indo-China, Malaysia, the Philippines, Indonesia, Oceania and sub-Saharan Africa 

(CABI, 2003). In the New World, it is present in Florida, and ranges from Mexico 

and Central America to northern South America and the Caribbean (CABI, 2002). 

We estimate that C. viridis could establish in the continental United States throughout

Plant Hardiness Zones 8-10 (USDA-NA, 2003).

Medium (2)

Risk Element #2: Host Range

This species is polyphagous. Primary hosts include Citrus spp. (Rutaceae), Coffea 

High (3)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 23

Coccus viridis (Green) (Hemiptera: Coccidae) Risk ratings

arabica (Rubiaceae), Artocarpus sp. (Moraceae), Camellia sinensis (Theaceae), 

Manihot esculenta (Euphorbiaceae), Mangifera indica (Anacardiaceae), Psidium 

guajava (Myrtaceae), and Theobroma cacao (Sterculiaceae) (CABI, 2002). Other 

hosts include Alpinia purpurata (Zingiberaceae), Chrysanthemum sp. 

(Asteraceae), Manilkara zapota (Sapotaceae), and Nerium oleander

(Apocynaceae) (CABI, 2002), Persea americana (Lauraceae) (Peña, 2003; BenDov et al., 2003).

Risk Element #3: Dispersal Potential

Females may deposit up to 500 eggs (CABI, 2002); there may be several generations 

per year (Kosztarab, 1997). In spite of the slow rate of natural dispersal (Tandon and

Veeresh, 1988), the scale can quickly spread through the transport of infested plant 

materials. Coccus viridis has been intercepted numerous times by PPQ on many plants 

from many countries (PestID, 2008).

High (3)

Risk Element #4: Economic Impact

Coccus viridis is a major pest of coffee in Haiti (Aitken-Soux, 1985) and India 

(Narasimham, 1987). In Brazil, infestations of 50 scales per plant caused significant 

damage to coffee seedlings, reducing leaf area and plant growth rate (Silva and Parra, 

1982). Coccus viridis is a major cause of yield loss in New Guinea coffee crop

(Williams, 1986). In India, the infestation of C. viridis and the sooty mold 

(Capnodium citri) that accompanied it significantly altered the quality of citrus fruit 

(Haleem, 1984). This pest is mostly known to be a minor pest of tropical crops, 

particularly coffee. Most of these hosts are not grown in the United States or of minor 

economic importance. In Florida the preferred host is groundsel bush, Baccharis 

halimifolia L., a non-cultivated plant. Preferred cultivated hosts are gardenia and 

ixora. In Florida, the records include 174 host plants for the green scale (Dekle

and Fasulo, 2001). This scale may occur on cultivated hosts in commercial 

nurseries and usually infestations are accompanied by sooty mold. Implementation 

of chemical control of the scale as well as the control of the ants protecting the 

scale from its natural enemies increases the cost of production (Dekle and Fasulo, 

2001).

High (3)

Risk Element #5: Environmental Impact

As a polyphagous organism, C. viridis is likely to attack native plants in the United 

States, some of which could be Threatened or Endangered (e.g., Senecio layneae –

CA; Cucurbita okeechobeensis – FL; Manihot walkerae – TX; Verbena californica -

CA) (USFWS, 2004). If this species were introduced to citrus production areas of 

California and Texas, it could have a negative impact and stimulate the initiation of 

additional biological control programs, such as release of predators (e.g., ladybird 

Chilocorus, caterpillars Eublemma, parasites Coccophagus, or the parasitic fungus 

Cephalosporium lecanii) (CABI, 2005). It is also possible, however, that native 

natural enemies in the new areas of scale introductions would be able to suppress 

populations of the pest. Thus, C. viridis is already present in Florida where several 

entomopathogenic fungi play an important role in the natural limitations of this scale 

on citrus (Peer Review, 2006). Chemical sprays that are already in place against 

other scale insects should be able to control C. viridis.

Medium (2)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 24

Ferrisia malvastra (McDaniel) (Hemiptera: Pseudococcidae) Risk ratings

Risk Element #1: Climate-Host Interaction

The species is widely distributed in Africa (from South Africa to Israel), Americas 

(from Argentina to Mexico), Australia, Oceania, and India (Ben-Dov et al., 2003). It 

is estimated that it could establish in Plant Hardiness Zones 7-10 of the Continental

United States (USDA-NA, 2003).

High (3)

Risk Element #2: Host Range

This species is widely polyphagous. The most important host families include 

Cruciferae (Brassica rapa), Euphorbiaceae (Euphorbia hirta, Manihot esculenta),

Lauraceae (Persea Americana), Fabaceae (Arachis hypogaea, Phaseolus vulgaris), 

Malvaceae (Gossypium hirsutum), Rutaceae (Citrus paradise), Solanaceae 

(Lycopersicon esculentum, Solanum tuberosum), Chenopodiaceae (Suaeda monoica), 

Compositae (Erigeron), Crassulaceae (Sedum) (Ben-Dov et al., 2003).

High (3)

Risk Element #3: Dispersal Potential

Note: We found no information about dispersal potential for this species. 

Consequently, we based our analysis on information for F. virgata.

In India, several overlapping generations occur per year, but only three generations 

occur in Egypt (CABI, 2003). Fecundity ranges from 109 to 185 eggs per 

generation, and may exceed 500. The oviposition period is 20-29 days, while the

incubation period is about 3-4 hours. Nymphs molted 3 (females) and 4 (males) 

times, and the development period varied from 26-47 and 31-57 days, 

respectively (CABI, 2003). Longevity of the adult female was 36-53 days and 1-3 

days for the male. The primary dispersal stage is the first instar, which naturally 

disperses by wind and animals. The females are active and mobile until they start 

to produce an ovisac and lay eggs. All life stages may be carried on consignments 

of plant material and fruit. Ferrisia malvastra was intercepted three times and 

Ferrisia sp. 153 times, with 43 interceptions in commercial and permit cargo

(PestID, 2008). We ranked this species High for this element.

High (3)

Risk Element #4: Economic Impact

Ferrisia malvastra is a widespread, polyphagous species (USDA, 2003a). 

Although it is not commonly known to be a significant plant pest, it has been 

confused with F. virgata and prior to recognition of F. malvastra as distinct from 

F. virgata, F. malvastra may have been misidentified as F. virgata (Culik et al., 

2006). It is considered to be a pest in the United States (Miller et al. 2002) and is 

of concern as a potential agricultural pest in Israel (Ben-Dov 2005). We found no 

good evidence that F. malvastra is a pest of economic significance, but it 

damages multiple species and is a vector of "swollen shoot", a virus disease of 

cacao in West Africa (Ben-Dov et al., 2003). Taking into account the pest's broad 

distribution, its polyphagy, and the ability to transmit a viral pathogen, we gave it 

a Medium rating for this risk factor. 

Medium (2)

Risk Element #5: Environmental Impact Medium (2)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 25

Ferrisia malvastra (McDaniel) (Hemiptera: Pseudococcidae) Risk ratings

As a polyphagous pest, F. malvastra is likely to attack native plants in the United 

States. Some of these could be Threatened or Endangered, such as Euphorbia

telephioides (FL), Manihot walkerae (TX), Suaeda californica,( CA), Erigeron

(E. decumbens – OR, E. maguirei – UT, E. parishii – CA, E. rhizomatus – NM), and 

Sedum integrifolium (MN, NY) (USFWS, 2004). Introduction of this species in areas

where the related species, F. virgata, is already present and controlled, may not lead 

to the initiation of additional programs

Potato Spindle Tuber Viroid (PSTVd) Risk ratings

Risk Element #1: Climate-Host Interaction

Climate is unlikely to limit the distribution of the viroid. PSTVd is found in a wide 

range of climates from temperate to tropical (CABI, 2004). Before being 

eradicated from the United States it was found in thirteen states from North 

Dakota to Mississippi, which corresponds to more than four hardiness zones. 

High (3)

Risk Element #2: Host Range 

The primary natural host of PSTVd is potato, but the viroid also affects tomato 

and other Solanum spp. (Peters and Runia, 1985). The experimental host range of 

PSTVd includes a wide range of Solanaceous species, as well as species from 

other families (Singh, 1973). Sweet potatoes (Ipomoea batatas) 

(Convolvulaceae), avocados (Persea americana) (Lauraceae) and Solanum 

muricatum have recently been described as hosts, in addition to wild Solanum 

spp. hosts (Salazar, 1989; Owens et al., 1992; Querci et al., 1995; Behjatnia et al., 

1996; Shamloul et al., 1997). The viroid attacks plant hosts from several families 

therefore the ranking is High.

High (3)

Risk Element #3: Dispersal Potential

PSTVd may be spread by contact between infected and healthy plants (CABI, 

2004). It may also be transmitted by pollen or aphid vectors (in association with 

PLRV) over short distances (CABI, 2004). The dispersal potential of the viroid in 

avocado fruit is unknown. In potato, tubers are the most important means of 

PSTVd dissemination over both long and short distances (Salazar, 1989). The 

increased use of true potato seed (TPS) for potato propagation is another 

potential avenue for spread of the disease if measures are not maintained to certify 

disease-free status (Singh and Crowley, 1985a; Salazar, 1989). 

Medium (2)

Risk Element #4: Economic Impact

PSTVd can cause up to a 90 percent yield reduction in avocado (Querci et al., 

1995) Losses in potato vary from 3 to 64 percent (Le Clerg et al.,1944; Singh et 

al., 1971). However, the severe strain reduced the yield by up to 64 percent. Reestablishment of PSTV in the seed potato producing areas of the United States 

could lead to the losses of potential markets. 

High (3)

Risk Element #5: Environmental Impact

There are no known host plants that are listed as Threatened or Endangered in the 

continental United States (USFWS, 2004). The environmental impact of the 

Low (1)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 26

Potato Spindle Tuber Viroid (PSTVd) Risk ratings

pathogen is likely to be minimal since the disease used to be widely spread 

throughout North America (CABI, 2004). 

Stenoma catenifer Walsingham (Lepidoptera: Oecophoridae) Risk ratings

Risk Element #1: Climate-Host Interaction

This moth is distributed in the Western Hemisphere, from Mexico to Brazil

(CABI, 2003). Suitable climatic conditions for this species in the Continental United 

States include Plant Hardiness Zones 9-10 (USDA-NA, 2003).

Medium (2)

Risk Element #2: Host Range 

The seed moth infests species in several genera of Lauraceae: Beilschmiedia, 

Chlorocardium rodiei (greenheart tree), Persea americana (avocado), P.

schiedeana (coyo) (CABI, 2003). We rated this factor Medium.

Medium (2)

Risk Element #3: Dispersal Potential

Females lay eggs on the skin of the fruit, and the larvae bore into the pulp and 

seed; on Persea (in environmental chamber), there could be approximately 164 

eggs laid per female, and up to 206 eggs per female on Chlorocardium rodiei

(CABI, 2003). The average life cycle is 46 days with thee generations per year 

(FAO, 1999). In tropical regions, this pest is present throughout the year due to 

the availability of host plants with diverse flowering periods (CABI, 2003). 

Stenoma catenifer populations increase during the growing season, reaching the 

highest level before harvest (CABI, 2003). Because larvae are internal, S. 

catenifer can be spread worldwide via humans.

High (3)

Risk Element #4: Economic Impact

Stenoma catenifer is a major pest of avocado in Latin America (CABI, 2003). 

The proportion of damaged fruit may reach 100 percent in Brazil (with total fruit 

loss), 80 percent in Venezuela, and 100 percent in Ecuador (CABI, 2003). 

High (3)

Risk Element #5: Environmental Impact

No plants in the genus Persea are listed as Threatened or Endangered (USFWS, 

2004), but several states do. Thus, P. borbonia (L.) Spreng. is endangered in 

Maryland and P. palustris (Raf.) Sarg. is endangered in Arkansas. Species from 

the Lauraceae family are Federally listed as Threatened and Endangered (e.g.,

Lindera melissifolia (Walt.) Blume). Preference tests were not conducted for 

these species, but they could be hosts for S. catenifer. If S. catenifer was 

introduced, new spray programs will likely be initiated since current programs

only target external lepidopteran avocado pests.(Bailey and Olsen, 1990a,b; Glenn 

et al., 2003). In Brazil, S. catenifer is currently controlled by organophosphates, 

carbamates, and pyrethroids (Ventura et al., 1999). In Mexico, insecticides have 

to be applied at least 12 times to be effective (Wysoki et al., 2002). New 

biological control programs could be developed based on the reports of the egg 

parasitism in natural populations. For example, in Brazil, natural egg infestations 

by Trichogramma pretiosum and Trichogrammatoidea annulata can reach 40

percent (Hohmann and Meneguim, 1993). One of these species (T. annulata) 

High (3)
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 27

Stenoma catenifer Walsingham (Lepidoptera: Oecophoridae) Risk ratings

occurs in the United States where it has been released against the navel orange 

worm (Peer Review, 2006). Introduction of the new control programs could be 

detrimental to the beneficial fauna of the current pests, however, there is a high 

degree of uncertainty to the exact impact. We are erring on the side of caution 

and assigning High ranking for this risk factor.

Table 5. Summary of the risk ratings for Consequences of Introduction

Pest Risk elements Overall 

ratinga

Climate / 

Host 

interaction

Host

Range

Dispersal 

potential

Economic

impact

Environ. 

impact

Anastrepha 

fraterculus

High (3) High (3) High (3) High (3) High (3) High (15)

Ceratitis capitata High (3) High (3) High (3) High (3) High (3) High (15)

Coccus viridis Med (2) High (3) High (3) High (3) Med (2) High (13)

Ferrisia malvastra High (3) High (3) High (3) Med (2) Med (2) High (13)

Potato Spindle Tuber 

Viroid

High (3) High (3) Med (2) High (3) Low (1) Medium (12)

Stenoma catenifer Med (2) Med (2) High (3) High (3) High (3) High (13)

a

Low is 5-8 points, Medium is 9-12 points and High is 13-15 points

2.6. Likelihood of Introduction

The rating for the Likelihood of Introduction is the sum of the ratings values for the Quantity 

Imported Annually and Pest Opportunity (Table 6). The likelihood that an exotic pest will be 

introduced depends on the amount of the potentially-infested commodity that is imported. The 

assessment of Pest Opportunity is based on the biological features exhibited by the pest‘s 

interaction with the commodity, and represent a series of independent events that must take place 

before a pest outbreak can occur. The five components are as follows: availability of postharvest 

treatments, whether the pest can survive through the interval of normal shipping procedures, 

whether the pest can be detected during a port-of-entry inspection, the interactions among factors 

that influence the rate of establishment, and factors affecting population establishment.

2.6.1. Quantity imported annually

The amount reported by the country of proposed export, in standard units of 40-foot long 

shipping containers (Table 6), was 250 containers in 2003, 375 in 2004, and 500 in 2005 

(SENASA, 2002b). This is greater than 100 containers, so the risk factor is High.

2.6.2. Survive Postharvest Treatment

We rated Anastrepha fraterculus, Ceratitis capitata, and Stenoma catenifer High for this subelement because the larvae are internal feeders that are not likely to be affected by a surface-
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 28

cleansing postharvest treatment, such as washing and culling, especially if the extent of the damage is 

not very obvious.

We rated Coccus viridis and Ferrisia malvastra Medium because they are external feeders that 

are likely to be dislodged by a surface-cleansing postharvest treatment. Depending on their stage 

(egg, immature, adult) or instar, however, these insects might find shelter on fruit, particularly at the 

calyx end, on a bumpy surface or in packing materials. The Coccoidea have sessile stages that live 

firmly pressed to plant surfaces; this posture and their water-repellent, waxy cuticles can make them 

difficult to see or dislodge, especially if sheltered at the stem end of the fruit.

Potato Spindle Tuber Viroid (PSTVd), like other viruses or viroids, is expected to survive treatment,

and we therefore rated it High risk.

2.6.3. Survive Shipment

We rated all of the pests High risk for this sub-element. The internal feeders are protected from 

adverse environmental conditions by the plant part tissue, while other pests are expected to take

shelter in rough or pitted areas on the plant part surface. Fruit can be shipped by airfreight, which 

makes delivery time short, and may or may not be refrigerated. The temperature conditions and 

time frames associated with un-refrigerated air or sea transport are insufficient to reduce 

population levels of these pests. Further evidence of the ability of numerous pests to survive with 

avocado fruit shipments is in the fact that, since 1985, officers at U.S. ports-of-entry have intercepted

17,402 pests on avocado fruit, including permit and general cargo, stores, quarters, mail, and passenger 

baggage (PestID, 2008). Interceptions from South America are presented below (Appendix A).

PSTVd replicates autonomously and moves systemically within the plant. The viroid would be 

expected to survive shipment and is therefore ranked High. 

2.6.4. Not Detected at the Port-of-Entry

We rated Anastrepha fraterculus, Ceratitis capitata, and Stenoma catenifer High risk for this subelement because these internal pests are only intercepted by destructive sampling. Depending on 

the age of infestation, the fruit fly pests can have a high probability of escaping detection at a port-ofentry; fruit fly-infested fruit can go unrecognized (White and Elson-Harris, 1992).

Staining of fruits by sooty molds and large, obvious infestations can lead to the easy detection of 

Ferrisia malvastra and Coccus viridis. Sparser populations of these relatively small insects 

(especially eggs and early instars), particularly if concealed at the stem end of fruits or in packing 

materials, would be more difficult to discover, despite the color differences with the plant part. 

Consequently, we rated these pests Medium.

PSTVd may not be detected upon entry. PSTVd has been found in potato seed (CABI, 2004).

Some avocado fruits exhibit pronounced symptoms (Querci et al., 1995), but these fruits are 

unlikely to be packed. It is unclear if asymptomatic fruit contain viable inoculum quantities, so we

ranked the pest Medium here.

2.6.5. Moved to a Suitable Habitat

Areas suitable for these pests to establish permanent populations include parts of the South and the 

West Coast of the continental United States, which comprises about 20 percent of the total land area. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 29

Domestic Hass avocado consumption indicates that states where avocados are grown—

California and Florida—annually consume an average of about 36 percent of the total volume 

of avocados from all sources (Bellamore, 2006). If Hass avocados from Peru are allowed 

entry into the entire United States market, we expect a proportionately high share of the 

imports will go to California and Florida.

Based on their known distributions in warm temperate and tropical climates, we rated all of the 

arthropods Medium for this sub-element due to their need for specific temperature ranges.

PSTVd can establish in a broad range of climates so there is a High likelihood of it being moved to a 

suitable climate. 

2.6.6. Contact with Host Material

This varies among the arthropods in their potential geographic range within the United States. Hosts of 

the polyphagous species Anastrepha fraterculus and Ceratitis capitata (see above) should be available 

throughout the potential range. We rated these pests High for this sub-element.

Hosts of Coccus viridis are more limited in distribution in the United States, and are therefore less 

likely to be contacted. Ferrisia malvastra hosts include some temperate-zone or widely cultivated 

plants (NRCS, 2003), but Coccoidea biology reduces the likelihood of successful establishment in the 

United States. Specifically, their sessile nature greatly limits the chances of contacting hosts (Miller, 

1985; Gullan and Kosztarab, 1997). Successful establishment of these insects in a new environment 

depends on at least two necessary conditions: close proximity of susceptible hosts, and presence on the 

imported fruit of  ̳crawlers‘ (or other mobile forms) to transfer to new hosts. Since these circumstances 

are highly unlikely to co-occur (Miller, 1985), we rated all scale insects Low for this element.

PSTVd is unlikely to come into contact with hosts. In potato, natural spread of PSTVd is through 

seed or aphid transmission (CABI, 2004). PSTVd and a related viroid Avocado Sunblotch Viroid 

(ASBVd) are known to be transmitted through seed or pollen of infected plants (Desjardins et al., 

1984; Fernow et al., 1970). Establishment would require infected seed or fruit tissue to come into 

contact with a host. This may require propagation of the seed rather than normal disposal; hence 

we rated the risk Low.

As mentioned above, Stenoma catenifer feeds on avocado and some other species from Lauraceae.

We expect the host range to include species of native Persea borbonia, P. humilis, and P. 

palustris, grown in South and South East of the Continental United States. The territory with the 

available hosts comprises approximately of less than 20 percent of total Continental United States 

(NRCS, 2006). For this reason, we rated it Medium for this factor.

Port-of-entry inspection will probably be inadequate to provide phytosanitary security for all 

quarantine pests that are likely to follow the pathway; therefore, the development of specific 

phytosanitary measures is recommended. Postharvest mitigation measures to reduce infestations 

of external and internal feeders are necessary and should be implemented for imports to be 

authorized. 
Pest Risk Assessment for Peru Avocados

Rev. 005 October 27, 2008 30

Table 6. Summary of the ratings for the Quantity Imported Annually, the Pest Opportunity, and the 

rating for the overall Likelihood of Introduction

Pest Quantity 

imported 

annually

Ratings for Pest Opportunity Likelihood of 

Introduction 

rating

Survive a

postharvest 

treatment

Survive 

shipment

Not detected 

at port-ofentry

Moved to

suitable 

habitat

Contact 

host 

material

Anastrepha 

fraterculus

High (3) High (3) High (3) High (3) Med (2) High (3) High (17)

Ceratitis capitata High (3) High (3) High (3) High (3) Med (2) High (3) High (17)

Coccus viridis High (3) Med (2) High (3) Med (2) Med (2) Low (1) Med (13)

Ferrisia malvastra High (3) Med (2) High (3) Med (2) Med (2) Low (1) Med (13)

Potato Spindle 

Tuber Viroid

High (3) High (3) High (3) Med (2) High (3) Low (1) High (15)

Stenoma catenifer High (3) High (3) High (3) High (3) Med (2) Med (2) High (16)

a

Low: 6 - 9 points, Medium: 10 - 14 points, High: 15 - 18 point

2.7. Conclusion: Pest Risk Potential and Phytosanitary Measures

The sum of the values for Consequences of Introduction and Likelihood of Introduction gives 

values for Pest Risk Potential (Table 7). This is a baseline estimate of the risks associated with this

importation, and the reduction of risk occurs through the use of mitigation measures.

Specific phytosanitary measures may be necessary for pests with a baseline Pest Risk Potential of 

Medium (Coccus viridis, Ferrisia malvastra). Both fruit flies, Anastrepha fraterculus and Ceratitis 

capitata, had High Pest Risk Potentials. The Guidelines (PPQ, 2000) state that a High Pest Risk 

Potential means that specific phytosanitary measures are strongly recommended, and that port-ofentry inspection is not considered sufficient to provide phytosanitary security. 

Note that any species of Heilipus seed beetles may later be considered to follow the pathway if 

these insects are intercepted on avocados imported from Peru. We included Heilipus sp. in the 

pest list based on two interceptions on avocado from Peru in baggage but this was not sufficient 

evidence to indicate that the pest follows the pathway. We have a high degree of uncertainty 

associated with the Heilipus species based mostly on a lack of sufficient evidence about this genus 

in Peru and its economic importance there. 

Likewise, uncertainty exists about whether or not other genera of seed weevils are associated with 

avocado in Peru. For example, Conotrachelus species were intercepted from Peru in permit and 

commercial cargo of different commodities, other than avocado (1985-2008; PestID, 2008). 

Despite this, we have no information on species of Conotrachelus that occur in Peru and may feed

on avocado. We therefore did not include any species from this genus in the pest list. Species 

from the genus Conotrachelus, however, are well known pests of avocados (Wysoki et al., 2002) 

and one or more of these species might occur on avocados in Peru. Seed weevils from genera 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 31

Heilipus and Conotrachelus are known to be in the pathway on avocados imported by the United 

States from other countries (7 CFR §319.56; PestID, 2008). 

The conclusions from pest risk assessment are used to decide whether risk management is 

required and the strength of measures to be used (Stage 2 of PRA) (IPPC, 2007: ISPM #2). Pest 

risk management (Stage 3 of PRA) is the process of identifying ways to react to a perceived risk, 

evaluating the efficacy of these procedures, and recommending the most appropriate options 

(IPPC, 2007: ISPM #s 2 and 14). We described risk mitigation options below, with their efficacy 

and application.

Table 7. Pest Risk Potential

Pest Consequences of 

Introduction

Likelihood of 

Introduction

Pest Risk Potentiala

Anastrepha fraterculus High (15) High (17) High (32)

Ceratitis capitata High (15) High (17) High (32)

Stenoma catenifer High (13) High (16) High (29)

Potato Spindle Tuber Viroid Medium (12) High (15) High (27)b

Coccus viridis High (13) Medium (13) Medium (26)

Ferrisia malvastra High (13) Medium (13) Medium (26)

a

Low = 11-18 points, Medium = 19-26 points and High = 27-33 points.

b Determined to be Low based on analysis in Appendix B.

3. Risk Mitigation

The appropriate level of protection associated with the risks of commodity importations can be 

achieved by the application of a single phytosanitary measure, such as inspection, quarantine 

treatment, or a combination of measures. Specific mitigations may be selected from a range of 

pre-harvest and post-harvest options (Table 8), and may include other safeguarding measures.

Measures may be added or the strength of measures may be increased to compensate for 

uncertainty associated with evidence of a risk. At a minimum, for a measure to be considered for 

use in a systems approach, it must be: 1) clearly defined; 2) efficacious; 3) officially required 

(mandated); and 4) subject to monitoring and control by the responsible national plant protection 

organization (IPPC, 2007: ISPM #14). 

A systems approach to mitigate risks involved with mature green  ̳Hass‘ avocado imports from 

Peru might combine a variety of measures: 1) certification of pest-free areas, pest-free places of 

production, or areas of low pest prevalence for certain quarantine pests; 2) programs to control 

pests within orchards (e.g., mechanical, chemical, cultural); 3) preclearance oversight by USDAAPHIS officials; 4) packinghouse procedures to eliminate external pests (e.g., washing, brushing, 

inspection of fruit); 5) quarantine treatments to disinfest fruit of internal and external pests; 6) 

consignments inspected and certified to be free of quarantine pests; 7) fruit traceable to origin, 

packing facility, grower, and field; 8) consignments subject to sampling and inspection after 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 32

arrival in the United States; and 9) limits on distribution and transit within the United States. 

3.1. Prior to Harvest

3.1.1. Pest-Free Areas

Establishment of pest-free areas, pest-free places of production, and pest-free production sites, as 

well as areas of low pest prevalence, may be an effective alternative to post-harvest quarantine 

treatments or a component of systems approach (IPPC, 2007: ISPM #14). If used, pest-free areas 

or production sites should be established and maintained in compliance with relevant ISPMs

(IPPC, 2007: ISPM #s 2, 10, and 22) and NAPPO Standard No. 17 (NAPPO 2004b). Export 

from Peru could be considered only from production areas that participate in the Integrated Fruit 

Fly Management program. Currently, this program includes trappings for fruit flies during the 

avocado growing season (SENASA, 2005). We that pre-harvest trapping programs are as 

important as monitoring population levels during the harvest season. Overall, the trapping 

schedules should satisfy the requirements of the appropriate international and regional standards, 

such as those mentioned above.

Fruit flies/Anastrepha fraterculus and Ceratitis capitata. Basic requirements for the trapping 

program for establishing fruit fly pest free areas (PFA) are found in NAPPO Standard No. 17 

(NAPPO, 2004b). Specific trapping levels for A. fraterculus and C. capitata should be identified 

in the Workplan and are not discussed in this document. In addition to the trappings, an exclusion 

of untreated host fruit imports into PFA is required. Also, mandatory are treatments of all capture 

sites and strict increase of trapping levels at first capture, trapping in pueblos as well as in 

orchards, suspension of exports on second capture in 1 sq mile in the same life cycle. We suggest 

a periodic APHIS review of the program and possibly a pre-clearance of shipments.

Seed moth/Stenoma catenifer. If used, establishing a pest-free area for this pest should be based 

on official sample prior to export season, orchard cleanliness, verification sampling and inspection 

of lots at harvest; certification of being harvested from pest free place of production.

The municipality should be surveyed at least annually and found to be free from the seed moth.

The survey should cover a specific area (as stated in the Workplan) and include randomly selected 

portions of each registered orchard and areas with wild or backyard avocado trees. The survey

should be conducted during the growing season and completed prior to the harvest of the 

avocados. Specifics for this survey could be similar to those approved for the importation of Hass 

avocados from Mexico into the United States as described in the Code of Federal Regulations (7 

CFR § 319, 2003). 

A second option is a pest-free place of production based on a higher level of official sampling, 

orchard cleanliness, and higher levels of verification samplings and inspections of lots at harvest as 

well as a phytosanitary certification of production in a pest free place. 

Scales/Coccus viridis and Ferrisia malvastra. Effective IPM programs achieving low pest 

prevalence of these scales combined with inspection is a possible mitigation option. Freedom from 

the scales could be verified by conducting an official survey or lot freedom based on inspection of 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 33

shipping lot. 

3.1.2. Control Program

Mechanical, cultural, or chemical means (e.g., orchard sanitation, pre-harvest insecticidal, 

fungicidal, and herbicidal sprays) could be used to control pests within the orchards routinely to 

achieve pest-free areas or pests-free production sites. Sanitation and pesticide applications, as 

essential components of best management practices, are mainstays of commercial fruit production 

(e.g., Kirk et al., 2001a).

3.1.3. Phytosanitary Certification Inspections

Fruit could be sampled and inspected periodically during the growing season and after harvest for 

quality control and as phytosanitary precautionary measures. Orchards could be surveyed 

periodically; at these times, a random sample of fruit per tree will be inspected to detect for 

presence of quarantine pests. Results of surveys must be negative for quarantine pests. Production 

areas also could be subject to scheduled audits and periodic, unannounced inspections by certified 

inspectors from PPQ and SENASA; these inspections will insure that production areas will meet 

stipulated requirements for the issuance of a phytosanitary certificate required for each 

consignment. This measure is useful for detecting pests present during the growing season that 

may be more difficult to detect post-harvest. Detection methods need to be combined with other 

measures to ensure the absence of pests of concern. Statistical procedures are available to verify, 

to a specified confidence level, the pest-free status of an area, given negative survey or trapping 

results (Barclay and Hargrove, 2005).

3.2. Post-harvest and Prior to Shipping

Removal of infected or infested plant material reduces the likelihood that quarantine organisms 

would be present with a shipment. Routine post-harvest and packing practices for avocados to be 

exported to the United States might include safeguards similar to those applied for avocados 

imported from Mexico (7 CFR § 319.56-2ff, 2003; now 7 CFR § 319.56-30, 2008). For example, 

removal and disposal of fallen avocado fruit from the orchard at least once every 7 days. Other 

safeguards might include placing fruit in containers or field boxes marked with an orchard

registration number, protecting fruit from fruit flies with insect-proof screens or tarpaulins before 

they are moved, or moving fruit from the orchard to the packinghouse within 3 hours of harvest.

Maintaining fruit identification from field boxes or containers to the shipping boxes would allow 

avocados to be traced back to the orchard of origin if pests are found at the packinghouse or 

during entry inspection in the United States.

In addition, the packinghouse might accept fruit only from orchards certified for participation in 

the avocado export program. To prevent insects from entering the packinghouse, all openings 

could be covered by screening or by some other barrier. The packinghouse could also have double 

doors at the entrance to the facility and at the interior entrance to the area where the avocados are 

packed.

Prior to the culling process, a sample of 300 avocados per shipment could be selected, cut, and 

inspected to be found free from quarantine pests.

Prior to being packed in boxes, each avocado fruit could be cleaned of all stems, leaves, and other 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 34

portions of plants to remove external pests. Most avocado fruit can be cleaned by gently wiping 

the surface with a clean soft cotton cloth or gloves. It may be necessary to use a moist cloth if the 

dirt particles or surface stains are difficult to remove. The cloth should periodically be dipped in a 

mild solution of household bleach (150 ppm hypochlorous acid or household bleach) to minimize 

the spread of possible latent diseases. Larger-scale operations may choose to clean the avocados 

by hand- rubbing individual fruit dumped in a tank of sanitized water. The wash water should be 

sanitized with 150 ppm hypochlorous acid (household bleach) maintained at a pH of 6.5. This is 

equal to 2 oz of household bleach (such as Marvex) per 5 gallons of water, or .3 liters of bleach 

per 100 liters of water. Avocadoes can also be cleaned mechanically by passing the fruit over a 

series of roller brushes wetted from above with spray nozzles (GMC, 2006). 

During the grading process, any damaged, diseased, or infested fruit could be removed and 

separated from the commodity destined for export. Each selected fruit should be labeled with a 

sticker that bears registration number of the packinghouse. Any avocados that have not been 

packed or loaded into a refrigerated truck or refrigerated container by the end of the work day 

must be kept in the screened packing area.

3.3. During Shipping and at U.S. Ports-of-entry

3.3.1. Shipping conditions

The boxes could be kept in a refrigerated truck or refrigerated container while in transit to the 

port of first arrival in the United States. Prior to leaving the packinghouse, the truck or container 

could be secured with a seal that will be broken when the truck or container is opened. Once 

sealed, the refrigerated truck or refrigerated container should remain unopened until it reaches the 

port of entry. Each shipment of avocados should be accompanied by a phytosanitary certificate 

issued by SENASA stating that all of the conditions of the Workplan have been met.

3.3.2. Limits on Distribution and Transit within the United States

Some imported commodities harboring exotic pests are authorized for shipment only to certain 

locations (e.g., Alaska or North Atlantic ports) or during a specific season (usually the one with 

the coldest temperatures). These additional measures limit the risk of establishment for many 

exotic pests. The importation of avocados into the United States is anticipated during the harvest

season in Peru, which is during May – August, with the peak harvest during June and July. These 

months are warmest in the continental United States and could be very suitable for survival of 

exotic pests. Shortening the importation season to May only and confining shipments to Alaska 

and North Atlantic ports during these months could somewhat increase the level of protection.

3.3.3. Point-of-entry Sampling and Inspection

Inspect consignments upon arrival in the United States, paying particular attention to paperwork, 

to ensure that the chain of custody has remained intact. A random sample of fruit from each 

consignment might be inspected (depending on the Workplan conditions) to detect a pest 

infestation rate of 10 percent or greater (USDA, 2004). 

3.3.4. Quarantine treatments

Fumigation and Refrigeration. Treatments of avocado against Mediterranean fruit fly, Ceratitis 

capitata, are governed by the rule 7 CFR § 305.2 (2008). Fumigation with methyl bromide at 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 35

normal atmospheric pressure followed by refrigerated storage in accordance with the procedures 

described in this section of the CFR is effective against the above mentioned fruit fly but is not 

effective against other dangerous pests of avocado. 

The fumigant is methyl bromide applied at normal atmospheric pressure with the dosage of two 

pounds per 1,000 cubic feet for 21⁄2 hours at 70o F or above. In addition, cold treatment T107-a is 

effective against Ceratitis capitata in avocado under 34oF for 14 days or 36ofor 18 days. For 

avocados from Peru, these specific treatments should be effective only against Ceratitis capitata. 

We have no current data on the efficacy of this treatment against the fruit flies Anastrepha spp. 

and the moth Stenoma catenifer on avocado. 

Many treatments are available, however, against Anastrepha spp. in other fruits and vegetables. 

For citrus, for example, the treatment is T101-j-2-1, which is fumigation with methyl bromide at 

NAP—chamber at 80—85o F with the condition that the infestation level is less than 0.5 percent 

of the lot. Another option for citrus is to treat Anastrepha spp. with high-temperature forced air 

treatment (Treatment: T103-a-1). For mango, to treat against Anastrepha spp., available 

treatment is T102-a Hot water dip. Apples, grapes, apricots, tangerine and other fruits could be 

subject to different schedules of Cold treatment against Anastrepha spp. Specific efficacy data are 

needed to verify that any of the available treatments against Anastrepha spp. could be used for 

treating this group of pests in avocado.

Treatment T104-a-1 and T104 -a-2 with methyl bromide at NAP------tarpaulin or chamber are

approved by APHIS for scale insects (Coccus viridis) and mealybugs (Ferrisia malvastra) at 70°

F or above (maximum dosage, 2 pounds/1,000 ft3), for 0.5 or 2.0 hours, depending on 

concentration readings.

Irradiation. Recently approved irradiation treatment with the generic dose of 400 Gy for all pests 

of the phylum Arthropoda, excluding adults and pupae of the order Lepidoptera could be a 

valuable option for controlling external pests Coccus viridis and Ferrisia malvastra and fruit flies 

Anastrepha spp., and Ceratitis capitata (Treatments for Fruits and Vegetables, 2006). The 

treatment could be questionable against the moth Stenoma catenifer since not all of its larvae 

pupate outside the fruit, in the soil, as reported in CABI (2005). In some cases, larvae pupate 

inside the seed (Arrellano Cruz, 1998) and thus, irradiation could be ineffective against this pest.

Irradiation dose of 150 Gy is effective treatment against fruit flies and could be used in 

combination with other measures to mitigate the rest of the pest complex. In spite of the 

effectiveness of the treatment against fruit fly pests, it appears that avocado fruit is sensitive to 

irradiation and even dose of 80 Gy causes loss of the fruit quality (Peer Review, 2006). It is the 

responsibility of exporting parties to decide regarding tradeoffs between efficacy of the treatment 

and its effect on the quality of the commodity. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 36

3.4. Monitoring

3.4.1. Pre-shipment Programs

Inspection, treatment, or other mitigative measures performed in the field and packinghouse 

should be under the direct supervision of qualified APHIS and SENASA personnel, and in 

accordance with specified phytosanitary procedures. Such programs call for monitoring of all 

aspects of any required phytosanitary measures, in addition to identifying the shortcomings and 

opportunities for program modifications. Provisions should be made for the formal recognition of 

approved areas, sites, or producers, as well as the specification of conditions for revoking 

approvals or refusing certification for export to the United States.

3.4.2. Field Survey and Trapping

Survey procedures include visual inspection, fruit cutting, and field trapping. Surveys should be 

conducted at regular intervals during the growing season to determine the presence or absence of 

pests. Specific methodologies of trappings and surveys for each quarantine pest of concern should 

be outlined in the Workplan. Growers will receive or be denied certification for export on the 

basis of survey or trapping results.

3.4.3. Shipments Traceable to Place of Origin in Peru

A system of identification labels and record keeping is required for avocado indicating the specific 

place of origin to ensure traceability to each production site.

3.5. Conclusions

The number and diversity of pests that require mitigation make it unlikely that a single mitigative 

measure will be adequate to reduce risks of their introduction into the United States. For this 

reason, a combination of measures in a systems approach is most feasible. The system should 

include the following safeguards: monitoring of orchards and management programs to achieve 

and maintain area pest freedom; packinghouse inspection and post-harvest treatments; and 

maintenance of consignment security and traceability in transit.

This document does not purport to establish specific work plans or to evaluate the quality of a 

specific program or systems approach. It identifies risks and provides information regarding 

known mitigative measures. The specific implementation of measures, as would be present in an 

operational Workplan, is beyond the scope of this document.

Table 8. Summary of risk mitigation options for Avocado from Peru

Measure(s) Pest Efficacy

Pest-free areas or places of 

production

All Satisfies requirements for

appropriate level of protection

Control program, including 

mechanical, cultural, or chemical 

means, and monitoring 

All Research required to

demonstrate efficacy

Fruit cutting samples combined Anastrepha spp., Adequate sampling size satisfies 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 37

Measure(s) Pest Efficacy

with low pest prevalence Ceratitis 

capitata, 

Stenoma 

catenifer 

requirements for appropriate level 

of protection

Packinghouse procedures, 

including cleaning, brushing, 

washing and visual culling

External feeders 

Coccus viridis

and Ferrisia 

malvastra

Research required to demonstrate 

efficacy on avocado. Washing with 

warm soapy water and brushing is used 

extensively against these pests in 

foliage and cut flowers.

Point-of-entry sampling and 

inspection including fruit cuttings

combined with other treatments

Most of the 

external pests; 

most of the 

internal pests 

when fruit is cut

Certain small insects, such as scales 

demonstrate low rate of detection 

during routine visual inspections.

Shaker-box technique and/or 

microscopic evaluations might be 

needed to reduce level of risk. For cut 

fruit, sample size should be adequate to 

detect infestation

Irradiation 150 Gy for fruit flies 

combined with low prevalence of 

other pests plus fruit cutting and 

inspection for Stenoma catenifer

All pests Research required to demonstrate

efficacy. Due to sensitivity of avocado 

to irradiation, data might be needed to 

identify a lower specific doze.

Methyl-Bromide fumigation 

(T104-a-1, schedule for 

mealybugs) combined with low 

pest prevalence

Coccus viridis Approved by APHIS to treat surface 

pests such as scales on vegetables, 

including avocado. 

Methyl-Bromide fumigation 

(T104-a-2, schedule for 

mealybugs) combined with low 

pest prevalence

Ferrisia 

malvastra

Approved by APHIS to treat 

mealybugs

Fumigation with Methyl-Bromide 

followed by cold treatment

Ceratitis capitata Approved by APHIS to treat certain 

fruit flies in avocado. 

Cold treatment Ceratitis capitata Approved by APHIS to treat C. 

capitata in avocado

Methyl-Bromide fumigation, or 

hot water dip, or high 

temperature forced air

Anastrepha spp. Different schedules approved by 

APHIS for a number of fruits. Research

required to demonstrate efficacy on 

avocado
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 38

4. Authors and Reviewers

CPHST, PERAL

Authors

Roger D. Magarey, Plant Pathologist

Marina Zlotina, Entomologist

Reviewers

Leah Millar, Entomologist

Heather Hartzog, Plant Pathologist

Michael Hennessey, Entomologist

5. Literature Cited

7 CFR § 319.56-2ff. 2003. U.S. Code of Federal Regulations, Title 7, Part 319 (7 CFR § 319.56-

2ff — Administrative instructions governing movement of Hass avocados from 

Michoacan, Mexico, to approved States).

7 CFR § 305.2. 2008. U.S. Code of Federal Regulations. Title 7, Part 305 (7 CFR § 305.2. 

Approved treatments).

7 CFR § 319.56-30. 2008. U.S. Code of Federal Regulations, Title 7, Part 319 (7 CFR § 319.56-

30 —Hass avocados from Michoacan, Mexico).

Aguiar-Menezes, E., E. Menezes, P. C. Cassino and M. A. Soares. 2002. Passion Fruit. In: Peña, 

J., J. Sharp and M. Wysoki, eds. Tropical Fruit pests and pollinators, CAB International, 

Wallingford, UK., pp., 361-390.

Aitken-Soux, P. 1985. Some pests and diseases generally encountered in coffee nurseries. Feuille 

Extens. Abstract. (53): 1-5 (in French).

Alata Condor, J. 1973. Lista de Insectos y Otros Animales Daninos a la Agricultura en el Peru.

Manual N 38. Ministerio de Agricultura, Direccion General de Investigacion Agraria, 

Centro Regional de Investigacion Agraria N1, Estacion Experimental Agricola de la 

Molina, Departamento de Entomologia. 176 pp.

Alfieri, S.A., Langdon, K.R., Wehlburg, C. and Kimbrough, J.W. 1984. Index of Plant Diseases in 

Florida. Bulletin 11. Florida Department of Agriculture and Consumer Services, Division 

of Plant Industry, Gainesville. 389 pp.

Alfieri, S. A., Langdon, K. R., Kimbrough, J. W., El-Gholl, N. E., and Wehlburg, C. 1993. 

Diseases and disorders of Plants in Florida. Florida Department of Agriculture and 

Consumer Services, Division of Plant Industry, Gainesville, Florida. pp. 1114. 

Aluja, M., Diaz-Fleischer, F., and J. Arredondo, J. 2004. Nonhost status of commercial Persea 

americana ―Hass‖ to Anastrepha ludens, Anastrepha obliqua, Anastrepha serpentina, 

and Anastrepha striata (Diptera: Tephritidae) in Mexico. J. Econ. Entomol. 97 (2): 293 –

309.

APHIS. 2006. Regulated plant pest list. http://www.aphis.usda.gov/ppq/regpestlist/. Last 

accessed October 2006. 

Anonymous, 1984. Distribution of Plant Parasitic Nematode Species in North America. Society of 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 39

Nematologists. 205 pp.

Anonymous. 1992. Radopholus similis. Pg. 390-395. In: Quarantine Pests for Europe. C.A.B. 

International, Wallingford, Oxon, U.K.

Anonymous. 2006a. Coleoptera: Histeridae present in the Entomological Museum of Lund 

University.

http://www.biomus.lu.se/zoomus/ZooDoc/VetSam/ZooEnt/OrdCol/ListCol/027Histeridae

.html.

Anonymous. 2006b. Arthropods of economic importance. Diaspididae of the world. 

http://ip30.eti.uva.nl/BIS/diaspididae.php?menuentry=sorten&id=80.

Arce, B. H., M. G. Valdivia R. C. Dongo, and R. M. Koc. 1974. Effect of fourteen fungicides on 

micro-organisms that affect seed germination of Yungas purple groundnut. Abstract. 

Invest. Agropec. 4 (1-2): 47-55 (in Spanish, English summary)

Arce, J. J. C., Peres, F.O. and F. E. Berti. 1987. Biologia do bicho do cesto Oiketicus kirbyi

(Lands.-Guilding, 1827) (Lepidoptera, Psychidae) em folhas de Eucalyptus spp. An. Esc. 

Sup. Agric. Luiz Queiroz. 44 (1) 341-358 (in Spanish, English summary).

Arellano Cruz, G. 1998. El ―barrenador del fruto del palto‖ Stenoma catenifer Walsh y su control 

natural en Chanchamayo y Satipo. Revis. Asoc. Peru. Ecol. 1 (1): 55-58 (in Spanish).

Bailey, J. B., and K. N. Olsen. 1990a. Chemical control of Amorbia, an insect pest of avocado 

and citrus. California Agric. 44:189-198.

Bailey, J.B., and K. N. Olsen. 1990b. Supplemental chemical control of omnivorous looper on 

avocados. California Agric. 44:8-9.

Ballou, C. H. 1936. El aguacate como planta hosperda del adulto de la mosca prieta. Rev. Gr. 

Com. y TArab. 5(5): 16. 312.

Barclay, H. J., and J. W. Hargrove. 2005. Probability models to facilitate a declaration of pestfree status, with special reference to tsetse (Diptera: Glossinidae). Abstract. Bull. 

Entomol. Res. 95(1): 1-11

Bazán de Segura, C. 1959. Principales Enfermedades de las Plantas en el Perú. Asociaciones de 

Agricultures de Cañete e Ica y el Comité de Defensa Técnica del Algodonero de la 

Sociedad Nacional Agraria [ed.], 70 pp.

Behjatnia, S.A.A., I.B. Dry, L.R. Krake, B.D. Condé, M.I. Connelly, J.W. Randles, M.A. 

Rezaian, 1996. New potato spindle tuber viroid and tomato leaf curl geminivirus strains 

from a wild Solanum sp. Abstract. Phytopathology, 86(8):880-886. 

Bellamore, T. 2006. Comment of the California Avocado Commission on Docket No. APHIS2006-0072, Availability of a Draft Risk Assessment for Hass Avocados from Peru. 

Ben-Dov Y. 2005. The malvastrum mealybug Ferrisia malvastra (Hemiptera: Coccoidea: 

Pseudococcidae), distribution, host plants and pest status in Israel. Phytoparasitica 33: 

154-156. 

Ben-Dov, Y., D. R. Miller, and G. A. P. Gibson. 2003. ScaleNet. 

http://www.sel.barc.usda.gov/scalenet/scalenet.htm. (Archived at PERAL)

BFW. 2004. Bundesamt und Forschungszentrum für Wald (BFW; Austrian Federal Office and 

Research Centre for Forests). Glasflügler, Erlenglasflügler und andere Arten - Sesia sp.

Bier, V.M. 1999. Challenges to the acceptance of probabilistic risk analysis. Risk Analysis 19 (4): 

703-710. 

Blackman, R.L., and V.F. Eastop. 2000. Aphids and the World‘s Crops: an Identification and 

Information Guide. 2

nd ed. John Wiley and Sons, Ltd. Chichester, England. 466 Pp.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 40

Bolland, H. R., J. Gutierrez, and C.H.W. Flechtmann 1998. World Catalogue of the Spider Mite 

Family (Acari: Tetranychidae). Koninklijke Brill NV, Leiden, The Netherlands. 392 Pp.

Brannen, P. M. 2004. Orange felt (Orange Cane Blotch) of Blackberry. The Southern Region, 

Small Fruits Consortium. (Vol. 4 No. 3).

Briceno, V. A. 1977. Notes on some arthropods of blackberry (Rubus spp.) in the Venezuelan 

Andes. Abstract. Frutas. 7 (33): 6-10 (in Spanish, English summary).

Bush, G.L. 1957. Some notes on the susceptibility of avocados in Mexico to attack by the 

Mexican fruit fly. Proc. Rio Grande Val. Hort. Soc. 11:75-78. 

CABI, 2002. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

CABI, 2003. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

CABI, 2004. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

CABI, 2005. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

CABI, 2007. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

Cavey, J. 2007. Email (April 05, 2007) from Joseph Cavey, Entomologist, USDA-APHIS-PPQ 

National Identification Services, to Marina Zlotina, Entomologist, USDA-APHIS-PPQCPHST Plant Epidemiology and Risk Analysis Laboratory (on file with USDA-APHISPPQ-CPHST-PERAL

C.M.I., 1964. Descriptions of Pathogenic Fungi and Bacteria No. 35. Phytophthora nicotianae

var parasitica. Commonwealth Agricultural Bureaux, England.

C.M.I., 1985. Distribution Maps of Plant Diseases No. 358. Rosellinia bunodes. Commonwealth 

Agricultural Bureaux, England.

Chavez, H., Pereira, C., and R. Gonzalez. 1985. Chicharrita del agucate Trioza perseae Tuthil 

(Homoptera: Psyllidae) plaga potebcial del aguacate en zones atlas Del estado de Lara.

Boletin de Entomologica Venzolana 4:17-24.

Chavez-Ramirez, F., Wang, X., Jones, K., Hewitt, D. and P. Felker. 1997. Ecological 

Characterization of O puntia Clones in South Texas: Implications for Wildlife 

Herbivory and Frugivory. Journal of the Professional Association for Cactus 

Development, 2: 9 -19. 

Chupp, E. 1953. A Monograph of the Fungus Genus Cercospora. Cornell University, Ithaca, NY.

667 pp.

Coetzee, M.P.A., B. Wingfield, P. Bloomer, G.S. Ridley, M.J. Wingfield. 2003. Molecular 

identification and phylogeny of Armillaria isolates from South America and IndoMalaysia. Mycologia 95: 285-293.

Coetzee, M.P.A., Wingfield, B.D., Harrington, T.C., Steimel, J., Coutinho, T.A., Wingfield, M.F. 

2001. The root rot fungus Armillaria mellea introduced into South Africa by early Dutch 

settlers. Molecular Ecology 10: 387-396.

Coile, H. and W. Dixon. 2000. Trilogy. 39. Florida Department of Ag. Cons. Services. 

Condit, I. J. 1915. The avocado industry in California. Proc. Am. Soc. Hort. Sci. 12: 13-22. 

Courneya, P. 2003. Email (October 17, 2003) from Paul Courneya, Entomologist, USDAAPHIS-PPQ National Identification Services, to Roger Magarey, Plant Pathologist, and 

Marina Zlotina, Entomologist, USDA-APHIS-PPQ- CPHST Plant Epidemiology and Risk 

Analysis Laboratory (Archived at PERAL).

Courneya, P. 2004a Email (February 24, 2004) from Paul Courneya, Entomologist, USDAAPHIS-PPQ National Identification Services, to Leah Millar, Entomologist, USDAAPHIS-PPQ- CPHST Plant Epidemiology and Risk Analysis Laboratory (Archived at 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 41

PERAL).

Courneya, P. 2004b. Email (February 25, 2004) from Paul Courneya, Entomologist, USDAAPHIS-PPQ National Identification Services, to Marina Zlotina, Entomologist, USDAAPHIS-PPQ- CPHST Plant Epidemiology and Risk Analysis Laboratory (Archived at 

PERAL).

Courneya, P. 2005 Email (January 03, 2005) from Paul Courneya, Entomologist, USDA-APHISPPQ National Identification Services, to Marina Zlotina, Entomologist, USDA-APHISPPQ- CPHST Plant Epidemiology and Risk Analysis Laboratory (Archived at PERAL)

Crous, P.W., Braun, U. 2003. Mycosphaerella and its anamorphs: 1. Names published in 

Cercospora and Passalora. Centraalbureau voor Schimmelcultures, Utrecht, The 

Netherlands. 571 pp.

Culik, M. P., D. dos S. Martins, and P. J. Gullan. 2006. First records of two mealybug species in 

Brazil and new potential pests of papaya and coffee. Journal of Insect Science 6:23

Dekle, G. W. and T. R. Fasulo. 2001. Featured Creatures: green scale Coccus viridis (Green) 

(Insecta: Hemiptera: Coccidae). http://creatures.ifas.ufl.edu/orn/scales/green_scale.htm.

Delgado, B. T. E, and S. C. Rosas. 1977. Cassava, results of research and recommendations for 

its cultivation in Peru. Abstract. Inf. Espec. Dir. Gen. Investig. Min. Aliment Peru. No. 65, 

30 Pp. (in Spanish, English summary).

Desjardins, P.R., Drake, R.J., Sasaki, P.J., Atkins, E.L., and Bergh, B.O. 1984. Pollen 

transmission of Avocado Sun Blotch viroid and the fate of the pollen recipient tree.

Abstract. Phytopathology 74:845.

Dominguez Gil, O. E. 1978. Insectos perjudiciales del guanabano (Annona muricata L.) en el 

Estado Zulia, Venezuela. Revista Facult. Agron. 4 (3): 149-163 (in Spanish). 

Ebeling, W. 1959. Subtropical Fruit Pests. University of California. 436 pp.

Farr, D. F., Bills, G.F., Chamuris, G.P. and A.Y. Rossman. 1989. Fungi on plants and plant 

products in the United States. Am. Phytopath. Soc., St. Paul, MN. 1252 pp.

Farr, D. F., A. Y. Rossman, M.E. Palm, and E.B. McCray (n. d.). 2004. Fungal Databases, 

Systematic Botany and Mycology Laboratory, ARS, USDA<http://nt.arsgrin.gov/fungaldatabases/fungushost/FungusHostDisplayFrame.cfm> : Last accessed 5 

Feb. 2004.

Fernow, K.H., Peterson, L.C., and Palaisted, R.L. 1970. Spindle Tuber Virus in seed and pollen 

of infected potato plants. Abstract. Am. Potato J. 47:75-80.

Foote, R.H., Blanc, F.L., and Norrbom, A.L. 1993. Handbook of the Fruit Flies (Diptera: 

Tephritidae) of America North of Mexico. Ithaca, NY: Comstock Publ. Assoc.

Gallegos, D. P., and E. J. Bonano. 1993. Consideration of uncertainty in the performance 

assessment of radioactive waste disposal from an international regulatory perspective.

Reliability Engineering and System Safety. 42: 111-123.

Glenn, H., J. E. Pena, R. Baranowski, R., and R. Duncan. 2003. Lepidopterous pests of Florida

avocado: biodynamics, mortality factors and control. Pests of avocado in Florida. Actas, V

Congreso Mundial del Aguacate, 19-24 Octubre, Granada-Malaga, 2:503-508.

GMC. 2006. Avocado Product Care. Guyana Marketing Corporation (GMC).

http://www.newgmc.com/avocado.html.

Gonzalez, F.R. and C.J. Abad. 1975. Armillaria mellea Quel. Departamento de Industrias 

Forestales. Revista Forestal del Peru. Lima, Peru. 6(1/2): 89-93.

Gullan, P.J. and M. Kosztarab. 1997. Adaptations in scale insects. Annu. Rev. Entomol. 42: 23-
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 42

50.

Gullan, P.J., D.A. Downie, and S. A. Steffan. 2003. A new pest species of the mealybug genus 

Ferrisia Fullaway (Hemiptera: Pseudococcidae) from the United States. Ann. Entomol. 

Soc. Am. 96(6): 723-737.

Gunn, C.R. and Ritchie, C. 1982. Report of the Technical Committee to Evaluate Noxious 

Weeds; Exotic Weeds for Federal Noxious Weed Act. (unpublished).

Haleem, S.A. 1984. Studies on fruit quality of sweet orange as affected by soft green scale and 

sooty mould. South Ind. Hort. 32(5): 267-269.

Harrington, T.C. 2000. Host specialization and speciation in the American wilt pathogen 

Ceratocystis fimbriata. Fitopath. Bras. 25S: 262-263.

Hassan, E. 1977. Major Insect and Mite Pest [sic] of Australian Crops. Gatton, Qld.: Ento Press.

Hill, D.S. 1983. Agricultural Insect Pests of the Tropics and Their Control, 2nd ed. Cambridge: 

Cambridge Univ. Press. 746 P.

Hodges, C. 2006. Ceratocystis fimbriata. Datasheet. National Information Center for State and 

Private Forestry. 

http://spfnic.fs.fed.us/exfor/data/pestreports.cfm?pestidval=106&langdisplay=english.

Hofshi, R. 2005. Peru – Avocado industry in the desert. In: Growers. 

http://www.avocado.org/growers/pages/growers_605.php.

Hohmann, C. L. and A. M. Meneguim. 1993. Preliminary observations on the occurrence of 

avocado borer, Stenoma catenifer Wals in the state of Parana. Anais da Sociedade 

Entomológica do Brasil, 22(2):417-419 (in Portuguese, English summary)

Hollis, D., and Martin, J.H. 1997. Jumping plantlice (Hemiptera: Psylloidea) attacking avocado 

pear trees, Persea americana, in the New World, with a review of Lauraceae-feeding 

among psylloids. Bull. Entomol. Res. 87 (5): 471-480.

Holm, L.G., D.L. Plucknett, J.V. Pancho, and J.P. Herberger. 1977. The World's Worst Weeds.

University of Hawaii Press, Honolulu. 609 pp.

Holm, L.G., Doll, J, Holm, E., Pancho, J., and J. P. Herberger. 1997. World Weeds: Natural 

Histories and Distribution. John Wiley and Sons, New York. 1129 pp.

Holm, L.G., Pancho J.V., Herberger J.P. and Plucknett. D.L. 1979. A Geographical Atlas of 

World Weeds. John Wiley and Sons, New York.

Hovore, F.T. 2003. Checklist of the Cerambycidae and Disteniidae (Coleoptera) of Costa Rica. 

http://64.233.161.104/search?q=cache:LLWOOwuc80J:www.hovore.com/pdf/Cerambycidae_of_Costa_Rica_2003.pdf+&hl=en&gl=us&ct

=clnk&cd=1.

Icochea, T., Duarte, V and Clark.C.A. 1994. Occurrence of sweetpotato chlorotic leaf distortion 

in Brazil and Peru caused by Fusarium lateritium. Plant Dis. 78: 754.

IPPC. 2007. International Standards For Phytosanitary Measures, 1 to 29 (2007 edition). Food 

and Agriculture Organization of the United Nations, Secretariat of the International Plant 

Protection Convention (IPPC), Rome, Italy. 376 pp.

Jiron, L., A. L. Norrbom, and J. Soto-Manitiu. 1988. A preliminary list of the fruit flies of the 

genus Anastrepha (Diptera: Tephritidae) in Costa Rica. Fla. Entomol. 71(2): 130-137.

Kaplan, S. 1992. 'Expert information 'versus 'expert opinions.' Another approach to the problem 

of elicting/combining/using expert knowledge in PRA. Reliab. Eng. System Safety 35: 61-

72.

Katsoyannos, B. I. 1983. Field observations on the biology and behavior of the black fig fly Silba 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 43

adipata (Diptera: Lonchaeidae) and trapping experiments. Abstract. Zeitsch. Angewan. 

Entomol. 95 (5): 471-476.

Kirk, K., R. Bessin, J. Hartman, J. O‘Leary and J. Strang. 2001a. Total quality assurance: apple 

production: best management practices. Kentucky Coop. Ext. Serv. ID-137. 

Kirk, M., Cannon, P.F. and David, J.C. 2001b. Dictionary of the Fungi. CABI Bioscience, UK.

Kosztarab, M. 1997. Deciduous forest trees, pp. 347-355. In Y. Ben-Dov and C.J. Hodgson 

(eds.). Soft Scale Insects: Their Biology, Natural Enemies and Control. Vol. 7B. 

Amsterdam: Elsevier Sci. Publ. B.V.

Lamberti, F., Jatala, P. and Agostinelli, A. 1987. A report of some Xiphinema species occurring 

in Peru (Nematoda, Dorylaimida. Nematologia Mediterranea. 15:103-109.

Laurencao, A., H. Soares, and G. Rosado-Neto. 2003. Occurrence and damage of Heilipus 

rufipes Perty (Coleoptera:Curculionidae) larvae in avocado trees (Persea Americana

Mill.) in the state of Ceara, Brazil. Neotrop. Entomol. 32: 363-364 (in Portuguese, 

English summary) <http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1519-

566X2003000200028&lng=en&nrm=iso&tlng=en> Last accessed 03 Oct. 2006.

Le Clerg E.L., Lombard P.M., Eddins A.H., Cook H.T., and Campbell J.C. 1944. Effect of 

different amounts of spindle tuber and leaf roll on yields of Irish potatoes. American 

Potato Journal, 21:60-71.

Lehman, P.S. 2002. Phytoparasitic nematodes reported from Florida. Florida Department of 

Agriculture.

Leston, D. 1979. The Species of Dagbertus (Hemiptera: Miridae) Associated with Avocado in 

Florida. Florida Entomologist, Vol. 62 (4): 376-379.

Liquido, N. J., R.T. Cunningham, and S. Nakagawa. 1990. Host plants of Mediterranean fruit fly 

(Diptera: Tephritidae) on the island of Hawaii (1949-1985 survey). J. Econ. Entomol. 83 

(5): 1863-1878.

Liquido, N. J., Barr P. G., and R. T. Cunningham. 1998. An encyclopedic bibliography of the host 

plants of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann). USDA-ARS-144, 

version 1, cd database.

Lopez, V. F., and Kairo, M. Y. K.. 1999. Coconut whitefly in Nevis. Pest Cabweb. Biocontrol 

News and Information. General News. 20 (1).

<http://pest.cabweb.org/Journals/BNI/Bni20-1/gennews.htm

McAlpine, J. and Steyskal, G. 1982. A revision of Neosilba with a key to the world genera of 

Lonchaeidae. (Diptera). Canadian Entomologist. 114: 105-129.

Mariau, D. 2001. [Diseases of Tropical Tree Crops]. Enfield, NH, USA: Science Publishers, Inc. 

and CIRAD, France. xi + 237 + illustrations. 

Marin Acosta, J.C. 1973. Preliminary list of pests of Annonaceae, sapodilla (Achras zapota L.) 

and guava (Psidium guajava L.) in Venezuela. Agron. Trop. 23(2): 205-216. [in Spanish; 

English summary].

Mendel, Z., Blumberg, D. and Wysoki, M. 1992. Biological control of four homopterans in Israeli 

horticulture: achievements and problems. Phytoparasitica. 20: 45-49.

Menge, J.A. and Ploetz, R.C. 2003. Diseases of avocado. In R.C. Ploetz. Diseases of Tropical 

Fruit Crops. CABI Publishing. CABI, UK, 527 pp.

Metcalf, R. L., and Metcalf, R.A. 1993. Destructive and Useful Insects, Their Habits and Control, 

Fifth Edition. McGraw-Hill Inc., New York.

Miller, D. R. 1985. Pest risk assessment of armored scales on certain fruit (USDA-ARS Report 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 44

submitted to USDA-APHIS-PPQ). USDA Agricultural Research Service, Beltsville, MD.

Miller, D. R. , G. L. Miller, and G. W. Watson. 2002. Invasive species of mealybugs (Hemiptera: 

Pseudococcidae) and their threat to U.S. agriculture. Proceedings of the Entomological 

Society of Washington 104: 825-836.

Miller, D., and J. A. Davidson. 2005. Armored scale insect pests of trees and shrubs (Hemiptera:

Diaspididae). Comstock Publishing Associates; Cornell Univ. Press, Ithaca, NY. 442 pp. 

Morgan, M.G., and M. Henrion. 1990. Uncertainty. Cambridge Univ. Press, United Kingdom 332 

pp.

Morin, L., Hill, R.L. and Matayoshi, S. 1997. Hawaii‘s successful biological control strategy for 

mist flower (Ageratina riparia) – can it be transferred to New Zealand. Biocontrol. 18 

(3): 77-88. 

Mourichon, X. 1994. Serious citrus dieback in Colombia caused by Ceratocystis fimbriata. Fruits 

Paris 49: 5-6, 415-416.

Nakahara, S. 1982. Checklist of the Armored Scales (Homoptera: Diaspididae) of the 

Conterminous United States. USDA, APHIS, PPQ. 110 pp.

NAPPO. 2004a. North American Plant Protection Organization‘s Phytosanitary Pest Alert 

System. Official Pest Reports: Absence of Potato Spindle Tuber Viroid (PSTVd) in the 

United States. Date posted: 03/04/2004.

http://www.pestalert.org/oprDetail_print.cfm?oprid=101.

NAPPO. 2004b. Guidelines for the establishment, maintenance and verification of fruit fly pest 

free areas in North America. NAPPO Regional Standards for Phytosanitary Measures No. 

17. Ottawa: Secretariat of the North American Plant Protection Organization. 

Narasimham, A.U. 1987. Scale insects and mealybugs on coffee, tea and cardamom and their 

natural enemies. J. Coffee Res. 17(1): 7-13.

NRCS. 2006. The PLANTS Database. United States Department of Agriculture, Natural 

Resources Conservation Service (NRCS), The National Plant Data Center. 

http://plants.usda.gov. (Archived at PERAL)

Norrbom, A.L. 2004. Host plant database for Anastrepha and Toxotrypana (Diptera: Tephritidae: 

Toxotrypanini). Diptera Data Dissemination Disk (CD-ROM) 2: 5,984 records

Noyes, J.S. 2003. Universal Chalcidoidea Database. World Wide Web electronic publication.

<www.nhm.ac.uk/entomology/chalcidoids/index.html>. Last accessed 29 Dec. 2004.

NRCS. 2003. The PLANTS Database. United States Department of Agriculture, Natural 

Resources Conservation Service (NRCS), The National Plant Data Center. 

http://plants.usda.gov. (Archived at PERAL)

NZPPO. 1999. Import Health Standard: Commodity Sub-class: Fresh Fruit/Vegetables avocado, 

Persea americana, from Tonga. New Zealand National Plant Protection Organization

(NZPPO). 14 P. http://www.maf.govt.nz/biosecurity/imports/plants/standards/avocadoto.pdf. Last accessed 16 Oct. 2003.

Orr, R. L., Cohen, S. D., and R. L. Griffin. 1993. Generic non-indigenous pest risk assessment 

process: "The generic process" (For estimating pest risk associated with the introduction 

of non-indigenous organisms). USDA-APHIS, Policy and Program Development, MD 40 

pp. 

Ovruski, S., Schliserman, P., and M. Aluja. 2003. Native and introduced host plants of 

Anastrepha fraterculus and Ceratitis capitata (Diptera: Tephritidae) in northwestern 

Argentina. J. Econ. Entomol. 96: 1108-1118.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 45

Owens R.A., Khurana S.M.P., Smith D.R., Singh M.N., and Garg I.D., 1992. A new mild strain 

of potato spindle tuber viroid isolated from wild Solanum spp. in India. Abstract. Plant 

Disease, 76(5):527-529. 

Peer Review. 2006. Peer review report for Importation of  ̳Hass‖ avocado (Persea americana) 

fruit from Peru into the Continental United States. August 30, 2006. USDA-APHIS-PPQ, 

Riverdale, MD.

Peña, J. E., and Bennett, F.D. 1995. Arthropods associated with Annona spp. in the Neotropics.

78 (2): 329-349.

Peña, J. E. 2003. Pests of avocado in Florida. Actas, V Congreso Mundial del Aguacate, 19-24 

Octubre, Granada-Malaga, 2:487-494.

Peña, J., Pantoja, A., Duncan, R., de Coss, M., Halbert, S., Evans, G. and Hammon, A. 2003.

Survey of Homopteran pests of papaya in Florida. Florida Entomological Society 2003 

Annual Meeting, July 27-30 2003, Hutchinson Island, FL. Abstracts (display 

presentations). <http://www.flaentsoc.org/2003annmeetabstracts.html.

PERAL. 2007. Phytosanitary Risks Associated with Armored Scales in Commercial Shipments of 

Fruit for Consumption to the United States, Revision Original. United States Department 

of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and 

Quarantine, Center for Plant Health Science and Technology, Plant Epidemiology and 

Risk Analysis Laboratory (PERAL), Raleigh, NC.

Perez, W. 1999. Fungi present on sexual seeds of maca (Lepidium meyenii Walp.). Fitopat. 34 

(1): 29-34 (in Spanish, English summary).

Perez, W., L. Gutarra, and E. French. 1994. Pythium ultimum Trow. causing watery rot in potato 

tubers in Peru. Fitopat. 29 (3): 191-195 (in Spanish, English summary).

PestID. 2008. Pest Identification Database (PestID). United States Department of Agriculture, 

Animal and Plant Health Inspection Service, Plant Protection and Quarantine. 

https://mokcs14.aphis.usda.gov/aqas/login.jsp. (Archived at PERAL)

Peters D. and W.T. Runia. 1985. The host range of viroids. In: Maramorosch K, McKelvey Jr JJ, 

eds. Subviral Pathogens of Plants and Animals; Viroids and Prions. New York, USA: 

Academic Press, 21-38.

Ploetz, R.C., Zentmyer, G.A., Nishijima, W.T., Rohrbach, K.G. and Ohr, H.D. 1994.

Compendium of Tropical Fruit Diseases. APS Press, American Phytopathological Society, 

St. Paul, MN. 88 pp.

Ponce, O. T., Pelaez, H. I., and De la Cruz, L. J. 1979. Biological study of the bagworm 

Oiketicus kirbyi Lands Guilding (Lepidoptera: Psychidae) on banana and a survey of its 

principal parasites. Acta Agronom. 29 (1-4): 41-46 (in Spanish, English summary).

PPQ. 2000. Guidelines for pathway-initiated pest risk assessments (Version 5.02). United States 

Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection 

and Quarantine (PPQ), Riverdale, MD. 30 pp.

PPQ. 2004. Regulating the Importation of Fresh Fruits and Vegetables (On-line manual.). United 

States Department of Agriculture, Animal and Plant Health Inspection Service, Plant 

Protection and Quarantine (PPQ).

http://www.aphis.usda.gov/ppq/manuals/pdf_files/20Fruits_and_Vegetables.pdf 

Putruele, M. T. G. 1996. Hosts for Ceratitis capitata and Anastrepha fraterculus in the 

northeastern province of Entre Ríos, Argentina, p. 343-345. In: B. A. McPheron & G. J. 

Steck, eds., Fruit fly pests: A world assessment of their biology and management. St. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 46

Lucie Press, Delray Beach. 586 p.

Querci, M., Owens, R.A., Vargas, C. and Salazar, L.F. 1995. Detection of potato spindle tuber 

viroid in avocado growing in Peru. Plant Disease. 79:196-202. 

Reed, C.F. 1977. Economically Important Foreign Weeds. Agriculture Handbook No. 498. 746 

pp. 

Renjifo, R.J., and C.F. Trujillo. 1992. Natural durability of the wood of nine species of 

Bombacaceae. Rev. For. Peru. 19 (1): 83-92 (in Spanish, English summary).

Rhainds, M., Gries, G. and Chinchilla, C. 1996. Development of a sampling method for first instar 

Oiketicus kirbyi (Lepidoptera: Psychidae) in oil palm plantations. J. Econ. Entomol. 89 

(2): 396-401.

Robinson, G.S., P.R. Ackery, I.J. Kitching, G.W. Beccaloni and L.M. Hernandez. 2004. HOSTS 

- A database of the hostplants of the world's Lepidoptera. The Natural History Museum. 

London, United Kingdom. <http://www.nhm.ac.uk/ entomology/hostplants/>. Last 

accessed 12 Nov. 2004.

Rosen, D. 1990a. Armored scale insects, their biology, natural enemies and control, Vol A., 

Elsevier, NY 383 p. 

Rosen, D. 1990b. Armored scale insects, their biology, natural enemies and control, Vol B., 

Elsevier, NY 688 p. 

San Juan, A. 2003. Leafcutter Ant Common Names. 

<http://www.blueboard.com/leafcutters/names.htm>. Last accessed 29 Oct. 2003.

Schubert, T. S. 2002. Letter to Leah Millar, Entomologist USDA-APHIS-PPQ. Email (June 25, 

2002) from Timothy Schubert, Mycologist, Florida Division of Plant Industry to Leah 

Millar, Entomologist, USDA-APHIS-PPQ, confirming the status of Mycena citricolor in 

Florida.

Salazar L.F., 1989. Potato spindle tuber. In Plant Protection and Quarantine. Volume II. Selected 

Pests and Pathogens of Quarantine Significance [edited by Kahn, R.P.]. Boca Raton, 

Florida, USA; CRC Press, Inc., 155-167. 

Seferssa. 2004. Diccionario de Especialidades Agroquimicas. FOLIDOL ® M-72.

<http://www.seferssa.com.mx/DEA/productos/204.htm>. Last accessed 29 Dec. 2004.

Seguenas, Y., E., and C. Corman Camara. 2002. Efecto del Neem Azadirchacta indica (Triology 

70 y Neemix 4.5) en el control de mosca blanca Aleurodicus cocois en el palto cultivado 

en Huimanal XLIV Convencion Nacional de Entomologia, Lima, 3-7 Nov. 2002. 100 

Universidad Nacional Agraria La Molina.

<http://www.lamolina.edu.pe/convencionentomologia/insecticidas_botanicos.htm> Last 

accessed 04 Oct. 2006.

SENASA. 2002a. Draft proposal for the application of pest risk mitigation measures in the 

exports of avocado (Persea American) to the United States of America from sites in Peru 

where the avocado seed moth (Stenoma catenifer) is not known to occur. Ministry of 

Agriculture, Peru.

SENASA. 2002b. Importation of avocado fruit (Persea Americana) from Peru. A Pest Risk 

Assessment. SENASA, Dec 2002.

SENASA. 2002c. Phytosanitary Status of the Avocado in Peru. Ministry of Agriculture, Peru.

SENASA. 2005. Fax from SENASA to Dr. Cathleen Enright from 14 June 2005. On file with 

USDA-APHIS. 

Shamloul A.M., Hadidi A., Zhu S.F., Singh R.P. and Sagredo B. 1997. Sensitive detection of 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 47

potato spindle tuber viroid using RT-PCR and identification of a viroid variant naturally 

infecting pepino plants. Abstract. Canadian Journal of Plant Pathology, 19(1):89-96. 

Silva, A. B. 1978. Aleurodicus cocois attacking pepper Piper nigrum in Para state, Brazil. Anais 

Soc. Entomol. Brasil. 6 (1): 136-137.

Silva, C.G. and Parra, J.R.P. 1982. Biology and injuriousness of Coccus viridis (Green, 1889) 

(Homoptera-Coccidae) on coffee seedlings (Coffea spp.). Abstract. An. Soc. Entomol. 

Brasil 11(2): 181-195. 

Silva, N.M., da Silveira Neto, S. and Zucchi, R.A. 1996. The natural host plants of Anastrepha in 

the state of Amazonas, Brazil, pp. 353-357. In B.A. McPheron and G.J. Steck (eds.). Fruit

Fly Pests: A World Assessment of their Biology and Management. Delray Beach, FL: St. 

Lucie Press.

Singh R.P. and Clark M.C., 1973. Similarity of host response to both potato spindle tuber and 

citrus exocortis viruses. Abstract. FAO Plant Protection Bulletin, 21(6):121-125.

Singh R.P. and Crowley C.F., 1985. Successful management of potato spindle tuber viroid in seed 

potato crop. Abstract. Canadian Plant Disease Survey, 65(1):9-10.

Singh R.P., Finnie R.E., and Bagnall R.H., 1971. Losses due to the potato spindle tuber virus. 

Abstract. American Potato Journal, 48:262-267.

Snell, W. 2006. Memo (October 27, 2006) from Wilmer Snell, PIM Trade Manager, USDAAPHIS-PPQ, to Marina Zlotina, Entomologist, USDA-APHIS-PPQ- CPHST Plant 

Epidemiology and Risk Analysis Laboratory (Archived at PERAL).

Sugayama, R.L., Malavasi, Nora, A.I. and Branco, E.S. 1996. Ovipositional responses to apple in 

a caged tree by Anastrepha fraterculus in southern Brazil, pp. 67-69. In B.A. McPheron 

and G.J. Steck (eds.). Fruit Fly Pests: A World Assessment of their Biology and 

Management. Delray Beach, FL: St. Lucie Press.

Swirski, E., Wysoki, M. and Ben-Dov, Y. 1997. Avocado, pp. 231-239. In: Y. Ben-Dov and C. J. 

Hodson [Eds.]. Soft Scale Insects – Their Biology, Natural Enemies and Control (7B).

Elsevier Science B.V. Amsterdam, The Netherlands. 442 Pp.

Tandon, P.L. and Veeresh, G.K. 1988. Inter-tree spatial distribution of Coccus viridis (Green) on 

mandarin. Int. J. Trop. Agric. 6(3/4): 270-275.

Thurston, H. D. 1989. [Tropical Plant Diseases 2nd Edition]. St. Paul, MN: The American 

Phytophathological Society. vii + 200p. 

Timmer, L.W. 2003. Sphaeropsis knot. In L.W. Timmmer, S.M. Garnsey, J.H. Graham Eds. 

―Compendium of Citrus Diseases.‖ 2

nd Edition. APS Press, St Paul, MN.

Torres, E. C. 1977. Phytoparasitic nematodes of sugarcane in Peru. Abstract. Nematrop. 7: 2 (in 

Spanish, English summary).

Treatments for Fruits and Vegetables. 2006. Federal Register 71(18): 4451-4464 (January 27, 

2006). 

Uchôa F., M. A., I. de Oliveira, R. M. S. Molina and R. A. Zucchi. 2002. Species diversity of 

frugivorous flies (Diptera: Tephritoidea) from hosts in the cerrado of the state of Mato 

Grosso do Sul, Brazil. Neotropical Entomol. 31: 515-524.

UCIPM. 2003. UC IPM Pest Management Guidelines: Avocado - Armored Scales. University of 

California Statewide Integrated Pest Management (UCIPM) Program.

<http://www.ipm.ucdavis.edu/PMG/r8300211.html . Last accessed 16 Oct. 2003.

Uramoto, K., Zucchi, R. A., and Walder, M. M. 2001. Biodiversity of Anastrepha fruit flies (Dip., 

Tephritidae) on the Luiz de Queiroz campus, Piracicaba, Sao Paulo, Brazil. Abstract, 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 48

Fourth Meeting of the Working Group on Fruit Flies of the Western Hemisphere, 

Mendoza, Argentina, November 21-25, 2001: 37-38.

<http://www.iicasaninet.net/pub/sanveg/pdf/4th_fruit_flies.pdf.> Last accessed 8/14/04.

U.S. Congress. 1993. U.S. Congress Office of Technology Assessment, Alternative Coca 

Reduction Strategies in the Andean Region, OTA-F-556 (Washington, DC: United States

Government Printing Office, July 1993). Chapter6. Coca biological control issues, P. 194.

<http://www.wws.princeton.edu/cgibin/byteserv.prl/~ota/disk1/1993/9307/930708.PDF>. Last accessed 12 Nov. 2004.

USDA. 2004. Agricultural Quarantine Inspection Monitoring (AQIM) Handbook. USDA-APHIS,

PPQ. (http://www.aphis.usda.gov/ppq/manuals/pdf_files/AQIM_Handbook.pdf). Last 

accessed 12 Oct. 2005. 

USDA-NA. 2003. The 2003 U.S. National Arboretum "web version" of the USDA Plant 

Hardiness Zone Map. United States Department of Agriculture (USDA), National 

Arboretum (NA). http://www.usna.usda.gov/Hardzone/ushzmap.html. (Archived at 

PERAL)

USFWS. 2004. Threatened and endangered species system (TESS). United States Fish and 

Wildlife Serv. http://ecos.fws.gov/tess_public/TESSWebpage. Last accessed 10 Oct.

2006.

Vallejos, O. V., and C. L. Mattos. 1990. Mycoflora of Oryza sativa L. and its relationship with 

aflatoxins in Lambayeque. Fitopatologia., 25 (2): 54-59 (in Spanish, English summary).

Vargas,C.O., Querci, M. and Salazar, L.F. 1991 Identification and dissemination of avocado 

sunblotch viroid in Persea americana L. in Peru and the presence of another viroid in 

avocado. Fitopatologia. 26:23-27.

Vasquez, J., C. Delgado, J. Couturi, and Matile-Ferrero. 2002. Harmful insects for the guava tree 

(Psidium guajava L: Myrtaceae) in Peruvian Amazonia. Fruits 57: 323-334 (in French, 

English summary).

Ventura, M., D. Destro, E. Lopes, and R. Montalvan. 1999. Avocado moth (Lepidoptera:

Stenomidae) damage in two avocado cultivars. Florida Entomol. 82: 625-631.

Vines, R. A. 1960. Trees, shrubs, and woody vines of the Southwest. University of Texas Press, 

Austin. 1104 p. 

Watson, A.J. 1971. Foreign Bacterial and Fungal Diseases of Food, Forage and Fiber Crops. 

Weems, H.V., Jr. 1981. Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: 

Tephritidae). Fla. Dept. Agric. Consumer Serv. Div. Plant Ind. Entomol. Circ. 230.

Weems, H. 2002a. Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae). Entomology 

Circular No. 217. FL. Department of Agriculture and Consumer Services, Division of 

Plant Industry. http://creatures.ifas.ufl.edu/fruit/.

Wellman, F. L. 1977. Dictionary of Tropical American Crops and their Diseases. Scarecrow 

Press, Metuchen, New Jersey. 495 pp.

White, I. M. and Elson-Harris, M. M. 1992. Fruit flies of Economic Significance: Their 

identification and bionomics. CAB International, Wallingford, UK. 601 pp.

Wille, J. E. 1952. Entomologia Agricola del Peru. Sanidad Vegetal, Direccion General de 

Agricultura, Ministerio de Agricultura, Lima, Peru [eds.], Aramburu Raybada HNOS.

S.A., Lima. 543 pp.

Williams, D.J. 1986. Scale insects (Homoptera: Coccoidea) on coffee in Papua New Guinea. Pap. 

New Guin. J. Agric. For. Fish. 34(1-4): 1-7.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 49

Wolfe, H, R. Franciosi, E. Van Oordt, and R. Figueroa. 1969. El culivo del palto en el Peru.

Minesterio de Agricultura y Pesqueria, Estacion experimental Agricola de La Molina, 

Lima, Peru, Bulletin Tecnico 73 (in Spanish). 

Wolfenbarger, D. O. 1948. Heilipus squamosus Lec., A new enemy of the avocado. California 

Avocado Society 1948 Yearbook. 33: 98-102.

WSSA. 2007. Composite List of Weeds. Weed Science Society of America (WSSA). 

http://www.wssa.net/Weeds/ID/WeedNames/namesearch.php. (Archived at PERAL)

Wysoki, M., M. A .Van den Berg, G. Ish-Am, S. Gazit, J. E. Peña, and G. K. Waite. 2002. Pests 

and Pollinators of Avocado, pp. 223-294. In: J. E. Peña, J. L. Sharp, and M. Wysoki 

[Eds]. Tropical Fruit Pests and Pollinators: Biology, Economic Importance, Natural 

Enemies and Control. CABI Publishing. 430 Pp.

Yarita Rubinos, Y. 2005. Ciclo Biologico y Algunos Aspectos Del Comportamiento de 

Dagbertus sp. (Hemiptera: Miridae) en Cultivo de Palto en el fundo Frusol, Viru La 

Libertad, Agosto 2004 a Marzo 2005

Zhang, B. C. 1994. Index of Economically Important Lepidoptera. CAB International, 

Wallingford, Oxon, UK. 599 pp.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 50

6. Appendices

Appendix A. Pest interceptions from selected countries in South America (excluding Peru)

from the pest identification database

(PestID, 2008)

38

Pest Countrya Total

ARG BOL BRA CHI COL ECU VEN

Abgrallaspis sp. (Diaspididae) 1 1 2

Agrotis sp. (Noctuidae) 25 1 26

Aleyrodidae, species of 1 1

Anastrepha sp. (Tephritidae) 2 2 1 5

Apion sp. (Curculionidae) 1 1

Arhyssus tricostatus (Spinola) (Rhopalidae) 1 1

Ascochyta, species of 1 1

Athlia rustica erichson (Scarabaeidae) 1 1

Aulacaspis tubercularis newstead 

(Diaspididae)

1 1 1 3

Blapstinus punctulatus solier 

(Tenebrionidae)

3 3

Blapstinus sp. (Tenebrionidae) 1 1

Bruchidae, species of 1 1

Cerambycidae, species of 1 1

Ceratitis capitata (Wiedemann) 

(Tephritidae)

1 1

Cladosporium sp. 1 1 2

Coccotrypes sp. (Scolytidae) 1 1

Coelomycetes, species of 1 1

Conoderus rufangulus (Gyllenhal) 

(Elateridae)

1 1

Conotrachelus perseae 1 1

Conotrachelus sp. (Curculionidae) 3 3

Copitarsia sp. (Noctuidae) 18 18

Crambidae, species of 1 1

Chrysomphalus pinnulifer (Diaspididae) 1 1

Curculionidae, species of 1 1

Diaspididae, species of 1 1 2 4

Diaspis sp. (Diaspididae) 1 1

 

38 Interceptions from Chile include commercial and permit cargo since Chile is the only country in South America from 

which commercial importations of avocados to the United States is authorized. All interceptions from other countries are 

from baggage, stores or holds due to the absence of trade in avocados from these countries. 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 51

Pest Countrya Total

ARG BOL BRA CHI COL ECU VEN

Elateridae, species of 1 1

Gelechiidae, species of 1 3 1 5

Geometridae, species of 1 1

Grammophorus minor (Schwarz) 

(Elateridae)

1 1

Gryllus sp. (Gryllidae) 2 2

Hadeninae, species of (Noctuidae) 15 15

Heilipus sp. (Curculionidae) 1 1 2

Heliothinae, species of 1 1

Hemiberlesia diffinis (Newstead) 

(Diaspididae)

1 1

Homoptera, species of 1 1 2

Hoplosphyrum griseus (Philippi) (Gryllidae) 9 9

Hylurgus ligniperda (Fabricius) (Scolytidae) 1 1

Lepidoptera, species of 1 1

Lepidosaphes sp. (Diaspididae) 2 2

Ligyrus villosus burmeister (Scarabaeidae) 5 5

Lithraeus egenus (Blanchard) (Bruchidae) 2 2

Melanaspis sp. (Diaspididae) 1 1

Micrapate scabrata (Erichson) 

(Bostrichidae)

1 1

Microgryllus pallipes philippi (Gryllidae) 5 5

Microsphaeropsis sp. 1 1

Monochaetinula sp. (Coelomycetes) 1 1

Noctuidae, species of 3 3

Nomophila sp. (Pyralidae) 2 2

Nysius sp. (Lygaeidae) 2 2

Oecophoridae, species of 1 1

Palinaspis sp. (Diaspididae) 1 1

Phaeoseptoria sp. 1 1

Phoma sp. 1 1 2

Phomopsis sp. 3 3

Phyllosticta sp. (Coelomycetes) 1 1

Pseudaletia impuncta (Guenee) (Noctuidae) 3 3

Pseudaletia sp. (Noctuidae) 1 1

Pseudaonidia trilobitiformis (green) 

(Diaspididae)

1 2 5 1 9
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 52

Pest Countrya Total

ARG BOL BRA CHI COL ECU VEN

Pseudococcidae, species of 1 141 2 3 146

Pseudococcus sp. (Pseudococcidae) 81 81

Pyraustinae, species of (Crambidae) 1 1

Rhyephenes sp. (Curculionidae) 1 1

Sitona sp. (Curculionidae) 1 1

Sphaceloma sp. 1 1

Stenoma catenifer Walsingham 

(Oecophoridae)

3 2 2 30 9 46

Syrphidae, species of 1 1

Tenebrionidae, species of 1 1

Tomarus villosus (Scarabaeidae) 6 6

Tortricinae, species of 2 2

Vinsonia stellifera (Coccidae) 1 1

a ARG – Argentina, BOL – Bolivia, BRA- Brazil, CHI – Chile, COL – Colombia, ECU –

Ecuador, VEN – Venezuela.
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 53

Appendix B. Likelihood of Entry, Introduction, and Establishment of Potato Spindle Tuber 

Viroid (PSTVd) with Imported ‘Hass’ Avocado, Persea americana, Fruit from Peru.

Executive Summary

In the Peruvian Avocado PRA, the consequences of introduction and likelihood of introduction of 

PSTVd were analyzed and rated as medium for both measures. Here we evaluated the likelihood 

of establishment based on three pathways, commercial fruit disposal, residential disposal, and seed 

propagation, and found the overall likelihood of establishment of the pest to be Low.

Pathways for Establishment

In the PRA it was determined that PSTVd is unlikely to come into contact with hosts. In potato, 

natural spread of PSTVd is through seed or aphid transmission (CABI, 2004). PSTVd and a 

related viroid, Avocado Sun blotch Viroid (ASBVd), are known to be transmitted through seed 

or pollen of infected plants (Desjardins et al., 1984; Fernow et al., 1970). Establishment would 

require infected seed or fruit tissue to come into contact with a host. We evaluate the likelihood 

of establishment based on three pathways, commercial fruit disposal, residential disposal, and seed 

propagation. We did not evaluate the likelihood of an irrigation water pathway but this was 

considered less likely.

1. Warehouse disposal pathway. To illustrate the fate of exotic organisms on imported fresh 

produce we used a relevant study. Eight pathways were investigated by Gould et al. (2004) in a 

risk analysis that looked at fresh asparagus infested with lepidopteran eggs. The study examined 

disposal methods at 14 commercial import warehouses in the United States that represented 85

percent of the asparagus imports from Peru. That report concluded that of the discarded product 

(not initially sold for consumption): 76.0 percent went unbagged into dumpsters; 4.5 percent went 

bagged into dumpsters; 11.2 percent was compacted then placed in landfill; 7.3 percent went to 

soup kitchens (consumed); 0.5 percent was put in the garbage disposal (municipal sewage); 0

percent went as discounted produce (consumed); 0 percent was composted; 0 percent went for 

animal feed. Dumpsters leading to landfills are a dead-end pathway for insect pests in municipal 

waste, such as Anoplophora glabripennis (Auclair et al., 2005). We assume that the same is true 

with this pathogen. PSTVd only moves with plant material in the absence of a vector. If all plant 

material is accounted for in the dumpsters and landfills, the viroid is mitigated if all insect vectors 

are considered mitigated.

2. Residential disposal pathways. Consumers purchase fruit and take it home from 

supermarkets. A first discard scenario includes consuming fruit, but discarding stems and calyxes 

into a garbage disposal and finally into the waste water (sewage) system. In a second discard 

scenario, stems and calyxes are bagged and put into the trash destined for landfill. In the United 

States over 75 percent of the population is served by centralized waste water collection and 

treatment, the remaining population using other on-site systems to treat sewage and waste water 

(EPA 2004; Zipper, 2003). Waste water (sewage) treatment standards have been developed to 

reduce populations of pathogens harmful to humans, and this may reduce the viability of PSTVd 

(EPA, 2004; Zipper, 2003). There are no studies on the quantity of fruits and vegetables 

discarded in backyard compost in the U. S. One foreign study estimated that up to 0.5 percent of 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 54

U. S. apples purchased in Japan ended up as compost (Roberts et al., 1998). Another study 

estimated that 5 percent of U. S. cherries purchased in New Zealand ended up as compost 

(Wearing et al., 2001). If it is assumed that 5 percent composting mirrors U. S. practices, then it 

is unlikely that the commodity would be discarded on compost piles. Although no studies have 

been done, it is assumed that all compost produced by consumers is used on home gardens or 

yards and not spread directly onto agricultural fields.

3. Seed Propagation pathway. Avocado seeds are frequently propagated in biology classes.

Often students are allowed to take their plants home after completion of the class. There is no 

data available to determine the fate of these plants but some assumptions can be made. Most 

plants would probably remain indoors and die and be disposed under considerations discussed 

above. The only possible scenario would be for a propagated tree to be planted outside in 

proximity to other hosts such as potato or avocado. The avocado tree is relatively frost sensitive 

and would not survive in most of the United States (Scorza and Wiltbank, 1975). For these 

reasons, we consider this pathway to be Low risk.

Conclusions

In the PRA it was determined that there would be a high probability of introduction. We 

conclude, however, that the probability of establishment is Low and, consequently, the overall 

probability of the pest following the pathway is Low.

Table 1. Likelihood of PSTVd following pathway based on establishment and introduction

Event Likelihood 

Consequences of Introduction High a

Likelihood of Introduction High a

Likelihood of establishment:

Warehouse disposal pathway

Consumer disposal pathway

Propagation pathway

Overall risk of establishment

Low

Low

Low

Low

Overall likelihood Low

a

From Risk Assessment above

Contacts

USDA-APHIS-PPQ-CPHST-PERAL, Raleigh, North Carolina,

Roger D. Magarey, Plant Pathologist (Roger.D.Magarey@aphis.usda.gov)

Marina Zlotina, Entomologist (Marina.A.Zlotina@aphis.usda.gov) 
Pest Risk Assessment for Avocado from Peru

Rev. 10 August 25, 2009 55

Literature cited

Auclair, A.N.D., Fowler, G., Hennessey, G., M.K., Hogue, A.T., Keena, M., Lance, D.R.,

McDowell, R.M., Oryang, D.O. and Sawyer, A.J. 2005. Assessment of the risk of 

introduction of Anplophora glabripennis (Coleoptera: Cerambycidae) in municipal solid 

waste from the quarantine area of New York City to landfills outside of the quarantine 

area: a pathway analysis of the risk of spread and establishment. J. Econ. Entomol.. 98:47-

60.

CABI, 2003. Crop Protection Compendium. CAB International (CABI), Wallingford, UK.

Desjardins, P.R., Drake, R.J., Sasaki, P.J., Atkins, E.L., and Bergh, B.O. 1984. Pollen 

transmission of Avocado Sun Blotch viroid and the fate of the pollen recipient tree.

Phytopathology 74:845.

EPA. 2004. Primer for Municipal Waste Water Treatment Systems. Environmental Protection 

Agency (EPA), Office of Water Management. Public. EPA 832-R-04-001. 30 pp.

Gould, J., Venette, R. and Seltzer, J. 2004. The pathways followed by fresh produce in the United 

States and how they impact the risk of establishment for exotic pests. Unpublished APHIS 

poster.

Fernow, K.H., Peterson, L.C., and Palaisted, R.L. 1970. Spindle Tuber Virus in seed and pollen 

of infected potato plants. Am. Potato J. 47:75-80.

Roberts, R. C., van der Zwet, T., Miller, C. E. and Redlin, S. C.. 1998. The potential for spread 

of Erwinia amylovora and fire blight via commercial apple fruit: A critical review and risk 

assessment. Crop Prot. 17: 19-28.

Scorza, R.SD. and Wiltbank, W.J. 1975. Evaluation of avocado cold hardiness Proceedings of

Florida State Horticultural Society. 88:496-499. 

Wearing, C. H., Hansen, J., Whyte, C., Miller, C. E. and Brown, J. 2001. The potential for spread

of codling moth (Lepidoptera: Torticidae) via commercial sweet cherry fruit: a critical 

review and risk assessment. Crop Prot. 20: 465-488.

Zipper, C. R. B. Renaue, Jr., and A. Jantrania. 2003. On-site sewage treatment alternatives. 

Virginia Coop. Extension Pub. 448-407. http://www.ext.vt.edu/pubs/waterquality/448-

407/448-407.pdf. Last accessed 13 July 2005.