Importation of Fresh Fruit of Tejocote (Crataegus pubescens

(Kunth) Steud.) from Mexico into the Continental United 

States

A Qualitative, Pathway-Initiated Pest Risk Assessment

Version 1 (Original)

March 28, 2011

Agency Contact

Plant Epidemiology and Risk Analysis Laboratory

Center for Plant Health Science and Technology

United States Department of Agriculture 

Animal and Plant Health Inspection Service

Plant Protection and Quarantine

1730 Varsity Drive, Suite 300

Raleigh, NC 27606
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 i

Executive Summary

In this document we assess the risks associated with the importation of tejocote or hawthorn 

apples, Crataegus pubescens (Kunth) Steud., from Mexico into the continental United States. We

did not identify any pests of quarantine significance likely to be introduced into the United States 

in commercial shipments of tejocote from Mexico.
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 i

Table of Contents

Executive Summary....................................................................................................................... i

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

1.1. Background........................................................................................................................ 1

1.2. Production.......................................................................................................................... 1

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

2.1. Initiating Event: Proposed Action...................................................................................... 2

2.2. Assessment of the Weed Potential of tejocote................................................................... 3

2.3. Current Status and Pest Interceptions................................................................................ 3

2.4. Pest Categorization ............................................................................................................ 3

3. Conclusion ................................................................................................................................. 8

4. Author and Reviewers.............................................................................................................. 8

5. References.................................................................................................................................. 8
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 1

1. Introduction

1.1. Background

This document was prepared by the Plant Epidemiology and Risk Analysis Laboratory of the 

Center for Plant Health Science and Technology, USDA Animal and Plant Health Inspection 

Service (APHIS), Plant Protection and Quarantine (PPQ), in response to a request to evaluate the 

risks associated with the importation of commercially produced fresh fruit of tejocote or 

hawthorn apple, Crataegus pubescens, from Mexico into the continental United States.

The International Plant Protection Convention (IPPC) provides guidance for conducting pest risk 

analyses. The methods used here are consistent with guidelines provided by the IPPC, 

specifically the International Standard for Phytosanitary Measures (ISPM) on ‘Pest Risk 

Analysis for Quarantine Pests, Including Analysis of Environmental Risks and Living Modified 

Organisms’ (IPPC, 2009: ISPM #11). The use of biological and phytosanitary terms is consistent 

with the ‘Glossary of Phytosanitary Terms and the Compendium of Phytosanitary Terms’ (IPPC, 

2009: ISPM #5). 

Three stages of pest risk analysis are described in international standards: Stage 1, Initiation, 

Stage 2, Risk Assessment, and Stage 3, Risk Management. This document satisfies the 

requirements of Stages 1 and 2. 

This is a qualitative risk analysis; estimates of risk are expressed in terms of High, Medium, and 

Low pest risk potentials based on the combined ratings for specified risk elements (PPQ, 2000) 

related to the probability and consequences of importing fresh tejocote fruit from Mexico. For 

the purposes of this assessment High, Medium, and Low probabilities will be defined as:

High: More likely to occur than not to occur

Medium: As likely to occur as not to occur

Low: Less likely to occur than not to occur

The appropriate risk management strategy for a particular pest depends on the risk posed by that 

pest. Identification of appropriate sanitary and phytosanitary measures to mitigate the risk, if 

any, for this pest is undertaken as part of Stage 3 (Risk Management). Other than listing possible 

mitigation options for the pests of concern, we did not discuss risk management in this 

document.

1.2. Production

Mexican hawthorn apple, or tejocote, is a tree fruit in the Rosaceae family. The import request 

describes the species as Crataegus pubescens (Kunth) Steud. and gives the synonym Crataegus 

mexicana Moc. & Sessé. According to Núñez-Colín (2008), Crataegus pubescens (Kunth) Steud. 

is a synonym of C. gracilior Phipps. Crataegus mexicana and C. gracilior (= C. pubescens), 

along with C. nelsoni Eggl. and C. stipulosa (Kunth) Steud., are common accessions of tejocote 

in the Germplasm Bank of Tejocote at the Autonomous University of Chapingo, and these 

accessions are mainly from three regional sources: the states of Puebla, Mexico, and Chiapas 

(Núñez-Colín et al., 2008).
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Ver. 1 March 28, 2011 2

The fruit appears similar to a small apple, yellow to orange in color, and from one to two 

centimeters in diameter. The trees are evergreen, flowering from January to April. The fruits are 

formed in spring and mature until November or December, when they are harvested. In Mexico, 

the fruit is commercially produced mainly in the states of Puebla, Oaxaca, and Chiapas (see Fig. 

1). Fruit is harvested by hand and packed in insect-proof boxes for export. SAGARPA estimates 

that 200 tons would be exported to the United States (SAGARPA, 2009).

Figure 1. Principal states of tejocote fruit production (SAGARPA, 2009).

2. Risk Assessment

2.1. Initiating Event: Proposed Action

We prepared this commodity-based, pathway-initiated pest risk assessment in response to a 

request for the USDA to authorize the importation of tejocote fruit grown in Mexico into the

continental United States. Tejocote fruit from Mexico provides a potential pathway for the 

introduction of plant pests. The movement of fruits and vegetables from Mexico into the United 

States is regulated in 7 CFR part 319 (2008). Currently, the entry of tejocote fruit from Mexico 
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 3

into the United States is not authorized under 7 CFR § 319; the government of Mexico seeks a 

change in this Federal Regulation to allow importation.

2.2. Assessment of the Weed Potential of tejocote

If the species considered for import poses a risk as a weed pest, then we do a “pest-initiated” risk 

assessment. The results of the weed screening for tejocote did not prompt a pest-initiated risk 

assessment (Table 1). 

Table 1. Determining the weed potential of tejocote.

Scientific name: Crataegus pubescens (Kunth) Steud. (Rosaceae)

Common Names: Mexican hawthorn, tejocote (SAGARPA, 2009)

Synonyms: Crataegus mexicana Moc. & Sessé

Phase 1: Distribution in the United States: Limited distribution in the United States 

(Kartesz, 2011)

Phase 2: Invasive / Weed Status: Listing as weed

No (Holm et al., 1977; Reed, 1977; Gunn and Ritchie, 1988; Holm et al., 1991; Holm 

et al., 1997; Weber, 2003; 7 CFR § 360, 2005; Skinner et al., 2005; Swearingen,

2005; WSSA, 2005)

No A Global Compendium of Weeds (Randall, 2002).

No Other scientific literature (see below).

Phase 3: Summary and Conclusions: Crataegus pubescens is listed as an unwanted tree, 

present in Australia (Henderson, 2001), but not otherwise noted as a weed in the 

scientific literature. Proceed with the pest risk assessment.

2.3. Current Status and Pest Interceptions

No requests have been made to import tejocote in the past. No pests have been intercepted on 

tejocote fruit entering the United States (PestID, 2011).

2.4. Pest Categorization

2.4.1. Pests associated with tejocote

In Table 2, we list the pests associated with tejocote (in any country) that occur in Mexico (on 

any host). In this list we identified the presence or absence of these pests in the United States, the 

generally affected plant part or parts, the quarantine status of the pest with respect to the United 

States, if the pest is likely to follow the pathway and enter the United States on commercially 

exported tejocote fruit, and pertinent citations for either the distribution or the biology of the 

pest. Based on pest biology and distribution, we eliminate many organisms from further 

consideration as sources of phytosanitary risk on tejocote from Mexico. 

Important notes regarding the pest list: 

 We do not provide information on plant part association and whether the pest is likely to 

follow the pathway for non-quarantine pests. Even if non-quarantine pests were able to 
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 4

follow the pathway, phytosanitary measures against these pests would not be justified 

because they already occur in the continental United States. Therefore, for nonquarantine pests we indicate that information with “N/A” (not applicable).

 Although Ceratitis capitata has been reported on Crataegus pubescens (Eskafi and 

Cunningham, 1987), this insect has been eradicated from Mexico (CABI, 2011).

 Pests in rows shaded gray, if any, are quarantine pests identified for potential risk 

mitigation, as we consider them reasonably likely to follow the pathway of commercial 

fruit shipments.

Table 2. Pests reported on tejocote (in any country) and present in Mexico. 

Scientific name & association 

with tejocote

Distribution1 Quarantine pestPlant part 

association

Follow 

pathway

ARTHROPODS

Coleoptera: Curculionidae

Anthonomus quadrigibbus Say

(CABI, 2011)

MX (CABI, 2011), US 

(CABI, 2011; Maier, 1990)

No N/A N/A

Contrachelus crataegi Walsh

(SAGARPA, 2009)

MX (SAGARPA, 2009), US 

(Maier, 1990)

No N/A N/A

Diptera: Agromyzidae

Liriomyza trifolii Burgess

(CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Diptera: Tephritidae

Rhagoletis pomonella Walsh

(SAGARPA, 2009)

MX, US (CABI, 2011) No N/A N/A

Hemiptera: Aleyrodidae

Siphoninus phillyreae (Haliday) 

(CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Hemiptera: Aphididae

Aphis spiraecola Patch (CABI,

2011)

MX, US (CABI, 2011) No N/A N/A

Eriosoma lanigerum 

(Hausmann) (CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Hemiptera: Cercopidae

Prosapia simulans (Walker) 

(SAGARPA, 2009)

MX (SAGARPA, 2009), US 

(CABI, 2011)

No N/A N/A

Hemiptera: Coccicidae

Coccus hesperidum L. (CABI,

2011)

MX, US (CABI, 2011) No N/A N/A

Ceroplastes ceriferus (Fabricius) 

(CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

 

1 Geographic Distribution: MX=Mexico, US=United States
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 5

Scientific name & association 

with tejocote

Distribution1 Quarantine pestPlant part 

association

Follow 

pathway

Parasaissetia nigra (Nietner) 

(Ben-Dov et al., 2011)

MX, US (Ben-Dov et al., 

2011)

No N/A N/A

Parthenolecanium corni

(Bouché) (CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Hemiptera: Diaspididae

Chrysomphalus dictyospermi 

Morgan (CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Diaspidiotus perniciosus 

(Comstock) (CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Epidiaspis leperii (Signoret) 

(CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Hemiptera: Pseudococcidae

Pseudococcus calceolariae

(Maskell) (CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

Lepidoptera: Papilionidae

Papilio eurymedon Lucas

(CABI, 2011)

MX (CABI, 2011), US 

(Tyler, 1975; Armstead,

2003)

No N/A N/A

Lepidoptera: Tortricidae

Crocidosema plebejana Zeller 

(CABI, 2011)

MX, US (CABI, 2011) No N/A N/A

FUNGI

Alternaria sp. (Alvarez, 1967) MX (Alvarez, 1967) Yes Leaf 

(Alvarez,

1967)

No

Armillaria mellea Vahl : Fr. P. 

Kumm. Anamorph: 

Rhizomorpha subcorticalis

Pers. ex Gray)] (SAGARPA,

2009)

MX (SAGARPA, 2009; 

Alvarez, 1976), US (Farr 

and Rossman, 2011)

No N/A N/A

Botryotinia fuckeliana de Bary 

Whetzel Anamorph: Botrytis 

cinerea Pers. : Fr. (SAGARPA,

2009)

MX (SAGARPA, 2009), US 

(Farr and Rossman, 2011)

No N/A N/A

Cladosporium sp. (Alvarez, 

1976)

MX (Alvarez, 1976) Yes Leaf

(Alvarez, 

1976)

No

Colletotrichum 

lindemunthianum Sacc. & 

Magn. Scrib (Garcia-Serrano 

et al., 2008)

MX (Garcia-Serrano et al., 

2008), US (Farr and 

Rossman, 2011)

No N/A N/A
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 6

Scientific name & association 

with tejocote

Distribution1 Quarantine pestPlant part 

association

Follow 

pathway

Colletotrichum sp. (Alvarez, 

1967)

MX (Alvarez, 1976) Yes Leaf, Fruit2 Yes3

Diaporthe sp. (Alvarez, 1967) MX (Alvarez, 1976) Yes Trunk, 

Branch 

(Alvarez, 

1976)

No

Fusarium sp. (Alvarez, 1967) MX (Alvarez, 1976) Yes Root 

(Alvrez, 

1976)

No

Gymnosporangium bethelii F. 

Kern4(Alvarez, 1976; 

Gallegos and Cummins, 

1981)

MX (Alvarez, 1976; Gallegos 

and Cummins, 1981), US 

(Farr and Rossman, 2011)

No N/A N/A

Gymnosporangium clavipes

(Cooke & Peck) Cooke & 

Peck 4(Gallegos and 

Cummins, 1981; Farr and 

Rossman, 2011)

MX (Gallegos and 

Cummins), US (Farr and 

Rossman, 2011)

No N/A N/A

Gymnosporangium globosum

Farl. Farl. (Anamorph: 

Aecidium globosum Farl.

(Alvarez, 1976; SAGARPA 

2009)

MX (Alvarez, 1976; 

SAGARPA, 2009), US 

(Jones and Aldwinckle, 

1990; Farr and Rossman, 

2011)

No N/A N/A

Gymnosporangium sp.

(Alvarez, 1967, 1976)

MX (Alvarez, 1967) Yes Fruit 

(Alvarez,

1967,

1976)

Yes3

Nectria cinnabarina Tode : Fr. 

Fr. Anamorph: Tubercularia 

vulgaris Tode : Fr. 

(SAGARPA, 2009)

MX (SAGARPA, 2009), US 

(Farr and Rossman, 2011 )

No N/A N/A

Nectria sp. (Alvarez, 1976) MX (Alvarez, 1976) Yes Trunk, 

branches 

(Alvarez, 

1976)

No

 

2 Reference specified the disease (anthracnose), but not the plant parts. Anthracnoses caused by species of 

Colletrotrichum are diseases of foliage, stems and fruit (Agrios, 2005), and congener C.lindemunthianum is 

reported on tejocote fruit (Garcia-Serrano et al., 2008).

3

Species of this genus occur in the United States, and the pathogen was not identified to species; therefore, this 

pathogen was not analyzed further.

4 Reported on Crataegus mexicana in Mexico (Gallegos and Cummins, 1981).
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 7

Scientific name & association 

with tejocote

Distribution1 Quarantine pestPlant part 

association

Follow 

pathway

Phyllosticta sp. (Alvarez, 

1976)

MX (Alvarez, 1976) Yes Leaf

(Alvarez, 

1976)

No

Phytophthora sp. (Alvarez, 

1976)

MX (Alvarez, 1976) Yes Root 

(Alvarez, 

1976)

No

Rosellinia necatrix Berl. ex 

Prill. Anamorph: 

Dematophora necatrix R. 

Hartig (Syn. Hypoxylon 

necatrix Berl. ex Prill. 

P.M.D. Martin) (SAGARPA,

2009)

MX (SAGARPA, 2009), US 

(Farr and Rossman, 2011 )

No N/A N/A

Venturia inequalis Cooke G. 

Winter; Anamorph: 

Fusicladium pomi Fr. : Fr. 

Lind (SAGARPA, 2009;

Farr and Rossman, 2011)

MX (SAGARPA, 2009; 

Alvarez, 1967), US (Farr 

and Rossman, 2011 )

No N/A N/A

BACTERIA

Erwinia amylovora Burrill 

Winslow et al. (SAGARPA,

2009)

MX (SAGARPA, 2009), US 

(CABI, 2011)

No N/A N/A

2.4.2. Quarantine pests not considered for further mitigation

Generally, based on standards by the International Plant Protection Convention (IPPC, 2009), we 

do not consider risk mitigation measures for organisms identified only to the genus level if the 

genus in question is reported in the continental United States. Often there are many species 

within a genus, and we cannot know if the unidentified species occurs in the continental United 

States and, consequently, whether it meets the definition of a quarantine pest for the continental 

United States. In this risk assessment, the above statement applies to the pathogens Alternaria

sp., Colletotrichum sp., Diaporthe sp , Fusarium sp , Cladosporium sp , Nectria sp., Phyllosticta 

sp., and Phytophthora sp. These genera are reported to occur in the continental United States 

(CABI, 2007; Farr and Rossman, 2010). Lack of specific identification may indicate the limits of 

current taxonomic knowledge, the life stage, or the quality of the specimen submitted for 

identification. Pest risk assessments focus on organisms for which biological information is 

available. Lack of specific identification does not rule out the possibility that a high-risk 

quarantine pest was intercepted. Conversely, the development of detailed assessments for known 

pests that inhabit a variety of ecological niches, such as internal fruit feeders or foliage pests, 

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

incompletely identified organisms that inhabit the same niche. If pests identified to higher taxa 

are intercepted in the future, we may reevaluate their risk.
Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 28, 2011 8

3. Conclusion

Since we identified no quarantine pests likely to follow the pathway of commercially imported 

tejocote fruit from Mexico, the pest risk assessment stops here. In the absence of quarantine pests 

likely to follow the pathway, the proposed irradiation may be unnecessary.

4. Author and Reviewers

Authors:

Shawn Robertson, Entomologist/Risk Analyst

Betsy Randall-Schaedel, Plant Pathologist/Risk Analyst

Reviewers:

Entomology, Luis Forero, Entomologist/Risk Analyst

Plant Pathology, Nancy Arciniegas/Plant Pathologist, Risk Analyst

Editor, Ashley M. Jackson 

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