## 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 27606Pest 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 2 8 , 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 2 8 , 2011 1 

### 1. Introduction **1.1 .**  **Background** This document was prepared b y the Plant Epidemiology and Risk Anal ys is Laboratory of the Center for Plant Health Science and Technology , USDA Animal and Plant Health Inspection Service (APHI S), 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 anal ys es. The methods used here are consistent with guidelines provided b y the IPPC, specificall y 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: I SPM #11). The use of biological and phy tosanitary terms is consistent with the ‘Glossary

of Phy tosanitary Terms and the Compendium of Phy tosanitary Terms’ (IPPC, 2009: I SPM #5). Three stages of pest risk anal ys is 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 anal ys is; 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 pur poses of this assessment High, Medium, and Low probabilities will be defined as: High: More likel y to occur than not to occur Medium: As likely

to occur as not to occur Low: Less likel y to occur than not to occur The appropriate risk management strategy for a particular pest depends on the risk posed b y that pest. Id entification of appropriate sanitary and phy tosanitary 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 famil y. The import request describes the species as Crataegus pubescens (Kunth) Steud. and gives the sy nony m Crataegus mexicana Moc. & Sessé. According to Núñez

- Colín (2008) , Crataegus pubescens (Kunth) Steud. is a sy nony m 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 mainl y from three regional sources : the states of Puebla, Mexico, and Chiapas (Núñez

- Colín et al. , 2008).Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 2 The fruit appears similar to a small apple, ye llow 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 commerciall y produced mainl y in the states of Puebla, Oaxaca, and Chiapas (see Fig. 1). Fruit is harvested b y 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.** Princip al 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 provide s a potential pathway for th e 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 MexicoPest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 3 into the United States is not authorized under 7 CFR § 319; th e 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 h awthorn, tej ocote (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 S**  **tatus 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 generall y 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 commerciall y 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 phy tosanitary 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 toPest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 4 follow the pathway , phy

tosanitary measures against these pests would not be jus tified because they

already occur in the continental United States. Therefore, for non

quarantine pests we indicate that information with “N/A ” (not applicable).
 Although Ceratitis capitata has been reported on Crataegus pubescens (Eskafi and Cunningham , 1 987), 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 likel y t o follow the pathway of commercial fruit shipments.

**T able 2.**  Pests reported on tejocote (in any country) and present in Mexico. **Scientific name & a**  **ssociation with**  **t ejocote**  **D istribution**  **1 Quaran** 
**** **tine pest Plant 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 StatesPest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 5 **Scientific name & a**  **ssociation with**  **t ejocote**  **D istribution**  **1 Quaran** 
**** **tine pest Plant 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 (Alvare z , 1976) Yes Leaf (Alvarez, 1976) No

Colletotrichum lindemunth ianum Sacc. & Magn. Scrib (Garcia

- Serrano et al. , 2008) MX (Garcia

- Serrano et al., 2008), US (Farr and Rossman, 2011) No N/A N/APest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 6 **Scientific name & a**  **ssociation with**  **t ejocote**  **D istribution**  **1 Quaran** 
**** **tine pest Plant part** 

**association Follow** 

**pathway** Colletotrichum sp. (Alvarez, 1967) MX (Alvarez, 1976) Yes Leaf , Fruit2 Yes 3 Diaporthe sp. (Alvarez, 1967) MX (Alvarez, 1976) Yes Trunk, B ranch (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) Yes 3

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. Anthracnose s caused by species of Colletrotrichum are diseases of foliage, stems and fruit (Agrios, 2005), and co ngener C.lindemunt hian um 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 wa s not analyzed further. 4 Reported on Crataegus mexicana in Mexico (Gallegos and Cummins, 1981).Pest Risk Assessment for Tejocote from Mexico

Ver. 1 March 2 8 , 2011 7 **Scientific name & a**  **ssociation with**  **t ejocote**  **D istribution**  **1 Quaran** 
**** **tine pest Plant part** 

**association Follow** 

**pathway** Phyllosticta sp. (Alvarez, 1976) MX (Alvare z , 1976) Yes Leaf (Alvarez, 1976) No
Phytophthora sp. (Alvarez, 1976) MX (Alvarez, 1976) Yes Root (Alv arez, 1976) No

Rosellinia necatrix Berl. ex Prill. Anamorph: Dematophora necatrix R. Hartig (Sy

n. 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 Rossm an, 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, consequentl y, whether it meets the definition of a quarantine pest for the continental United States. In this risk ass essment, 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 i dentification. 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 detail ed 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 2 8 , 2011 8 

### 3. Conclusion Since we identified no quarantine pests likel y to follow the pathway of commerciall y imported tejocote fruit from Mexic o , the p est risk a ssessment stops here

. In the absence of quarantine pests likely to follow the pathway, the proposed irradiation may be unnecessary

. 

### 4. Author and Reviewers **Author s**  **:** Shawn Robertson, Entomologist/Risk Analyst Bets y 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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