“B”
An pest of known economic or environmental detriment and, if present in California, it is of limited distribution. B-rated pests are eligible to enter the state if the receiving county has agreed to accept them. If found in the state, they are subject to state endorsed holding action and eradication only to provide for containment, as when found in a nursery. At the discretion of the individual county agricultural commissioner they are subject to eradication, containment, suppression, control, or other holding action.
John J. Chitambar, Primary PlantPathologist/Nematologist, California Department of Food and Agriculture, plant.health[@]cdfa.ca.gov.
Updated on 7/10/2019 by ls
John J. Chitambar, Primary PlantPathologist/Nematologist, California Department of Food and Agriculture, plant.health[@]cdfa.ca.gov.
Updated on 7/10/2019 by ls
The risk of infestation of Citrus viroid V (CVd-V) in California is evaluated and a permanent rating is herein proposed.
Background: The origin of Citrus viroid V (CVd-V) is uncertain (Serra et al., 2008a). In a study in Spain on the response of Citrus species and citrus-related genera to viroid infections, Serra and other researchers (2008a) originally detected CVd-V in Atalantia citroides, a citrus relative plant propagated on rough lemon rootstock and graft-inoculated with artificial mixtures of different viroids. The viroid source was provided to them by a researcher at the University of California, Riverside and purified preparations were shown to be infectious in Etrog citron (Citrus medica), a classical indicator plant of citrus viroids. Subsequently, CVd-V was considered a new species of the genus Apscaviroid in the family Pospiviroidae (Serra et al., 2008a). Viroids are classified within two families: Pospiviroidae and Avsunviroidae. Citrus are natural hosts of several viroid species that belong to the family Pospiviroidae. Therefore, A. citroides was identified as an unusual viroid host since it was resistant to all previously known citrus viroids, yet capable of replicating CVd-V (Serra et al., 2008b). Infectious assays conducted by Sierra et al. (2008) showed that CVd-V in Etrog citron exhibited mild symptoms, however, co-infections with either Citrus bent leaf viroid (CBLVd) or Citrus dwarfing viroid (CDVd, previously Citrus viroid III), also belonging to the genus Apscaviroid, showed synergistic effects in contrast to single infections of CVd-V or the other two viroids, however, titers of the viroids remained the same in singly or doubly infected plants (Serra et al., 2008a).
While the origin of CVd-V is not known, Pakistan may be one of the geographic origins of the viroid (Serra et al., 2008a, b; Parakh et al., 2017). Serra et al. (2008a) suggested that the viroid was present, but overlooked or unnoticed, in field sources containing Hop stunt Viroid or Citrus dwarfing viroid – both of which have electrophoretic mobilities similar to CVd-V. CVd-V has been found with some variations in its nucleotide sequence, in several countries in Africa, Asia, Europe, and North America (see ‘Worldwide Distribution).
In June 2016, the Citrus Clonal Protection Program-National Clean Plant Network (CCPP-NCPN), University of California, Riverside, California detected Citrus Viroid V in citrus budwood samples submitted by the CDFA for virus and viroid testing under the mandatory California (CA 3701) Citrus Nursery Stock Pest Cleanliness Program. These budwood samples were taken from asymptomatic redblush grapefruit (Citrus paradisi) and variegated calamondin (C. madurensis) from a nursery in Tulare County. This find marked the natural occurrence of CVd-V in California and corroborated the earlier report of CVd-VCA variant in the State (Dang et al., 2018; Serra et al., 2008b).
Hosts: Citrus spp. including ‘Sanguinelli’, Salustiana’, and ‘Ricart navelina’ sweet oranges (Citrus x sinensis), ‘Oroval’ and ‘Hernandina clementines (C. clementina), ‘Fino’ and ‘Verna’ lemons (C. limon), ‘Sevilano’ and ‘Cajel’ sour orange (C. aurantium), ‘Clausellina’ satsuma (C. unshiu), Temple mandarin (C. temple), Tahiti lime, Palestine sweet lime (C. limettioides), calamondin (C. madurensis), ‘Calabria’ bergamot (C. bergamia), ‘Orlando’ tangelo (C. paradisi x C. tangerina), ‘Page’ mandarin [(C. paradisi x C. tangerina) x C. clementina], and ‘Nagami’ kumquat (Fortunella margarita), and Etrog citrus (Atlantia citroides) (Serra et al., 2008); ‘Shiranui’ [(C. unshiu x C. sinensis) x C. reticulata] (Ito and Ohta, 2010); ‘Moro blood’ sweet orange (Citrus x sinensis) (Bani Hashemian et al., 2013); redblush grapefruit (C. paradisi) (Dang et al., 2018).
Symptoms: Citrus viroid V induced mild characteristic symptoms of very small necrotic lesions and cracks, sometimes filled with gum, in the stems of the viroid indicator plant, Etrog citron. However, CVd-V reacted synergistically when Etrog citrus was co-infected with either citrus bent leaf viroid (CBLVd) or Citrus dwarfing viroid (CDVd), and showed severe stunting and epinasty with multiple lesions in the midvein. Plants co-infected with CBLVd and CVd-V exhibited severe stem cracking characteristic of CBLVd, but without gum exudates, whereas plant co-infected with CDVd showed necrotic lesions (Serra et al., 2008a). Symptoms induced by CVd-V alone in commercial species and varieties are presently not known since commercial trees may be co-infected with several viroids (Ito and Ohta, 2010; Serra et al., 2008a). Citrus viroid V may be present in asymptomatic citrus plant tissue – as recently evidenced by its detection in asymptomatic budwood collected from Tulare County, California.
Damage Potential: The effect of CVd-V in commercial citrus rootstock-scion combinations, alone and in combination with other viroids, is yet unknown, however, Serra et al. (2008b) suggested that CVd-V could reduce tree size and yield as has been reported for clementine trees grafted on trifoliate orange co-infected with several viroids. Therefore, the need for nursery planting stock free of CVd-V is important.
Transmission: Similar to other citrus viroids, CVd-V is graft-transmitted and is spread mainly through the propagation of infested material.
Worldwide Distribution: Africa: Oman (Serra et al., 2008), Tunisia (Hamdi et al., 2015); Asia: China, Japan, Nepal, Pakistan (Cao et al., 2013), Iran (Bani Hashemian et al., 2010), Turkey (Önelge and Yurtmen, 2012); Europe: Spain (Serra et al., 2008); North America: USA (Serra et al., 2008).
Official Control: Citrus viroid V is a disease agent of concern that is tested for in the CDFA Citrus Nursery Stock Pest Cleanliness Program (3 CCR §§ 3701, et seq.).
California Distribution: Tulare County (Dang et al., 2018).
California Interceptions: None reported.
The risk Citrus viroid V would pose to California is evaluated below.
1) Climate/Host Interaction: Citrus viroid V is likely to establish within infested propagative citrus materials in all citrus-growing regions of California.
Evaluate if the pest would have suitable hosts and climate to establish in California.
Score: 3
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Citrus viroid V has a moderate host range that is limited to several species and varieties of Citrus.
Evaluate the host range of the pest.
Score: 2
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Citrus viroid V replicates autonomously within infested plants and is spread mainly through the propagation and movement of infested planting materials to non-infested regions.
Evaluate the natural and artificial dispersal potential of the pest.
Score: 2
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: The effect of CVd-V in commercial citrus rootstock-scion combinations, alone and in combination with other viroids, is yet unknown, however, it has been suggested by Serra et al. (2008b) that CVd-V could reduce tree size and yield.
Evaluate the economic impact of the pest to California using the criteria below.
Score: A, B, C
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 3
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: It is probable that home, urban, public garden and landscape plantings of CVd-V-infested citrus plantings may be significantly impacted by the viroid singly or in combination with other viroids.
Evaluate the environmental impact of the pest on California using the criteria below.
Environmental Impact: E
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact Score: 2
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here. (Score)
-Low = 5-8 points
–Medium = 9-12 points
-High = 13-15 points
Total points obtained on evaluation of consequences of introduction of CVd-V to California = 12.
6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)
-Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
Evaluation is Low (-1). Currently, Citrus viroid V has only been detected in a nursery in Tulare County.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)
Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 11.
The effect of CVd-V in commercial citrus rootstock-scion combinations, alone and in combination with other viroids, is yet unknown.
Based on the evidence provided above the proposed rating for Citrus viroid V is B.
Bani Hashemian, SM, Taheri, H, Duran-Vila, N, and Serr, P. 2010. First report of Citrus viroid V in Moro blood sweet orange in Iran. Plant Disease 94: 129.
Cao, M. J., Liu, Y. Q., Wang, X. F., Yang, F. Y., and Zhou, C. Y. 2010. First report of Citrus bark cracking viroid and Citrus viroid V infecting Citrus in China. Plant Disease 94: 922. https://doi.org/10.1094/PDIS-94-7-0922C
Dang, T., Tan, S. H., Bodaghi, S., Greer, G., Lavagi, I., Osman, F., Ramirez, B., Kress, J., Goodson, T., Weber, K., Zhang, Y. P., Vidalakis, G. First report of Citrus Viroid V naturally infecting grapefruit and calamondin trees in California. Plant Disease, Posted online on August 10, 2018. https://doi.org/10.1094/PDIS-01-18-0100-PDN
Hamdi, I., Elleuch, A., Bessaies, N., Grubb, C. D., and Fakhfakh, H. 2015. First report of Citrus viroid V in North Africa. Journal of General Plant Pathology 81, 87
Ito, T., and Ohta, S. 2010. First report of Citrus viroid V in Japan. Journal of General Plant Pathology 76: 348-350.
Önelge, N., and Yurtmen, M. 2012. First report of Citrus viroid V in Turkey. Journal of Plant Patholology 94 (Suppl. 4), 88.
Parakh, D. B., Zhu, S., and Sano, T. 2017. Geographical distribution of viroids in South, Southeast, and East Asia. In: Apscaviroids Infecting Citrus Trees by Tessitori, M, Viroids and Satellites, Edited by Hadidi, A, Flores, R, Randles, JW, and Palukaitis, P, Academic Press Ltd-Elsevier Science Ltd, Pages 243-249
Serra, P., Barbosa, C. J, Daros, J. A., Flores, R., Duran-Vila, N. 2008a. Citrus viroid V: molecular characterization and synergistic interactions with other members of the genus Apscaviroid. Virology 370, 102112.
Serra, P., Eiras, M., Bani-Hashemian, S. M., Murcia, N., Kitajima, E.W., Daro`s, J. A., et al., 2008b. Citrus viroid V: occurrence, host range, diagnosis, and identification of new variants. Phytopathology 98, 11991204.
John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-738-6693, plant.health[@]cdfa.ca.gov.
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Posted by ls
On September 27, 2017, a shipment of desert rose (Adenium obesum) plants showing symptoms of leaf spot disease was intercepted by San Diego Agricultural County inspectors. The shipment had originated in Florida and was destined to a private company in San Diego County. A sample of symptomatic plant leaves was collected by the San Diego Agriculture County and sent to the CDFA Plant Pathology Laboratory in Sacramento. On October 18, 2017, the fungus, Corynespora cassiicola, was identified by CDFA plant pathologist, Suzanne Latham, to be associated with the leaf spot symptoms. A temporary ‘Q’ rating was assigned to the pathogen and consequently, the shipment was destroyed. Corynespora cassiicola was previously detected on May 7, 2008, in an intercepted shipment of Mandevilla plants that originated in Florida and was destined to a nursery in San Diego County. This detection marked the first report of the pathogen in California and resulted in the destruction of the shipment. The current rating and consequences of introduction of C. cassiicola in California are assessed here and a permanent rating is proposed.
Background: Corynespora cassiicola is a fungal plant pathogen that attacks a wide range of plants from tropical and subtropical countries causing leaf spot disease in several economically important crops under different common names such as Corynespora leaf spot of cucumber and several other hosts, blotch disease of cucurbits, stem and fruit spot of eggplant, papaya and target spot of tomato and cotton. The fungus has been found in plant leaves, stems, fruit, roots, nematode cysts, and human skin and comprises many isolates. Majority of isolates reported have been obtained from lesions or from fulfilled Koch postulate trials and are known to be plant pathogens. However, isolates have also been reported from dead organic matter and non-symptomatic plant tissue and some can be both depending on the host substrate (Dixon et al., 2009). Isolates may vary in virulence in host specificity. Some isolates that specifically parasitize weed hosts without affecting agricultural crops may serve as potential bioherbicides agents (Smith & Schlub, 2005). In South-east Asia, C. cassiicola causes leaf fall disease of rubber, which is one of the most serious leaf diseases of rubber in that region.
The pathogen was first described as Helminthosporium cassiicola by Berkeley and Curtis in 1868, and subsequently underwent several taxonomic changes to now be known as Corynespora cassiicola (Farr & Rossman, 2018). This pathogen is ubiquitous and has been reported to cause major economic losses in more than 70 countries (Dixon et al., 2009).
Disease cycle: The pathogen survives in infested plant materials for more than two years. High humidity, warm temperature (25-32°C) and long days are necessary for conidia production, infection and disease development. Fluctuating day and night temperatures favor disease development (Williams, 1996). The disease develops in tomatoes at favorable temperatures of 20-28°C and infection can occur at 16-32°C. Extended periods of 16 to 44 hours of high moisture are necessary for optimum disease development (Pernezney et al., 2014).
Dispersal and spread: Infested planting stock, plant material, plant debris. Conidia (spores) are airborne and seedborne (Daughtrey et al., 1995).
Hosts: More than 530 plant species from 380 genera including monocots, dicots, ferns, and one cycad have been reported to support growth of C. cassiicola (Dixon et al., 2009). Economically important host crops for California include Cucumis sativus (cucumber), Cucurbita moschata (pumpkin), C. moschata (pumpkin), C. pepo (marrow), cucurbits, Gossypium sp. (cotton), Solanum lycopersicum (tomato), S. melongena (eggplant) and ornamentals (CABI, 2018; Farr & Rossman, 2018). Ornamental hosts include Aeschyanthus pulcher (lipstick vine), Aphelandra squarrosa (zebra plant), Catharnathus roseus (Madagascar periwinkle), Begonia, Hydrangea macrophylla (bigleaf hydrangea), Euphorbia pulcherrima (poinsettia), Saintpaulia ionantha (African violet) and Salvia splendens (scarlet sage) (Daughtrey et al., 1995)
Symptoms: The initial symptoms of target spot in tomato are pinpoint-size, water-soaked lesions on the upper surfaces of leaves. These lesions increase in size, turn circular and pale brown with individual yellow halos. Over time lesions coalesce and tissue may collapse while the leaflet remains attached to the petiole. Similar lesions may develop on petioles and stems resulting in rapid collapse of affected leaflets. Lesions can develop on young fruit and resemble those caused by abiotic factors. These lesions are initially dark, sunken, pinpoint and brown and may later develop into craters. On ripe fruit, large, circular lesions develop with pale brown centers that crack and over time create avenues for secondary invading pathogens (Pernezny et al., 2014). In infected cucurbits, initial lesions are angular yellow spots with light brown centers and dark brown borders. As these lesion age, they drop out. Young and green fruit are not susceptible however, early infection of the blossom end of fruit may result in shriveling and darkening of the infected area with dark sporulation (Williams, 1996). On ornamental plants such as poinsettia, lesions may be irregular, large and brown on bracts and primarily at the tips and margins of leaves; on hydrangea lesions may be small, reddish purple, circular with tan centers and reddish-purple margins; on African violets lesions are irregular and brown (Daughtrey et al., 1995).
Damage Potential: In the USA, reports of losses from target spot of field tomatoes are restricted to the Southeast which is frequented with high humidity and warm temperature climate (Pernezny et al., 2014). In California, if left uncontrolled, Corynespora disease development is likely to occur in greenhouses under favorable temperature and high humidity conditions. Impact of disease caused by this pathogen may be mitigated through proper sanitation, use of resistant varieties and regular applications of fungicidal treatments.
Worldwide Distribution: Asia: Bangladesh, Brunei Darussalam, Cambodia, China, India, Indonesia, Japan, Republic of Korea, Laos, Malaysia, Maldives, Myanmar, Nepal, Pakistan, Philippines, Singapore, Sri Lanka, Taiwan, Thailand, Vietnam, Yemen; Africa: Benin, Cameroon, Congo, Democratic Republic of Congo, Côte d’Ivoire, Egypt, Ethiopia, Gabon, Ghana, Guinea, Liberia, Mauritius, Nigeria, Seychelles, Sierra Leone, South Africa, Sudan, Tanzania, Togo, Uganda, Zambia; Central America and Caribbean: Antigua and Barbuda, Barbados, Belize, British Virgin Islands, Costa Rica, Cuba, Dominica, El Salvador, Guadeloupe, Guatemala, Haiti, Honduras, Jamaica, Nicaragua, Puerto Rico, Trinidad and Tobago, United States Virgin Islands; Europe: Austria, Bulgaria, Denmark, France, Germany, Hungary, Italy, Netherlands, Norway, Romania, Russian Federation, United Kingdom, Ukraine; North America: Canada, Mexico, USA; Oceania: American Samoa, Australia, Fiji, Guam, Micronesia, New Zealand, northern Mariana Islands, Palau, Papua New Guinea, Samoa, Solomon Islands, Vanuatu; South America: Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Venezuela (CABI, 2018).
In the United States, C. cassiicola has been reported from Alabama, Florida, Hawaii, Illinois, Iowa, Louisiana, Minnesota, Mississippi, Nebraska, New York, North Carolina, North Dakota, South Carolina, Tennessee, Virginia, and Wisconsin (CABI, 2018).
Official Control: Corynespora cassiicola is on the ‘Harmful Organism Lists” for Israel, Namibia, South Africa and Vietnam (USDA PCIT, 2018).
California Distribution: Corynespora cassiicola has not been reported from California. The pathogen is not known to be established in California.
California Interceptions: There have been two interceptions of plants infected with Corynespora cassiicola (see: ‘Initiating Event’).
The risk Corynespora cassiicola would pose to California is evaluated below.
1) Climate/Host Interaction: Corynespora cassiicola requires prolonged periods of high humidity (16-44 hours) and warm temperature (25-32°C) for disease development. These climatic conditions would limit the ability of the pathogen to establish and spread within California.
Evaluate if the pest would have suitable hosts and climate to establish in California. Score: 1
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: The pathogen has a very wide and diverse host range that comprises more than 530 plant species from 380 genera including monocots, dicots, ferns, and one cycad. Economically important host crops for California include cucurbits, cotton, tomato, eggplant and ornamentals.
Evaluate the host range of the pest.
Score: 3
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Conidia are produced in abundance and are dispersed by air currents, infected seeds, host plant material and debris. Therefore, a high score is given to this category.
Evaluate the natural and artificial dispersal potential of the pest.
Score: 3
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Plant damage caused by cassiicola is more likely under prolonged periods of high humidity and warm temperatures found in greenhouse cultivation than in open field environments of the state. If left uncontrolled, infections by the pathogen could result in lower crop yield and value resulting in the loss of markets. However, the administration of proper control measures may mitigate impact of damage caused by this pathogen. Therefore, a medium score is given to this category.
Evaluate the economic impact of the pest to California using the criteria below.
Economic Impact: A, B
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 2
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: No significant impact to the environment is likely as the requirements of prolonged, high humidity and warm temperatures would considerably limit the ability of cassiicola to establish within the state.
Evaluate the environmental impact of the pest on California using the criteria below.
Environment Impact: None
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact Score: 1
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here. (Score)
-Low = 5-8 points
–Medium = 9-12 points
-High = 13-15 points
Total points obtained on evaluation of consequences of introduction to California = 10
6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.
Evaluation is ‘Not established’ in California and has only been detected in intercepted plant shipments to the State.
Score: (0)
–Not established (0) Pest never detected in California, or known only from incursions.
-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)
Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 10
None.
Based on the evidence provided above the proposed rating for Corynespora cassiicola is B.
Agrios, G. N. 2005. Plant Pathology (Fifth Edition). Elsevier Academic Press, USA. 922 p.
Daughtrey, M. L., Wick, R. L., and Peterson, J. L. 1995.Corynespora leaf spot of Catharanthus, Hydrangea, Poinsettia, and Saintpaulia. In, Compendium of Flowering Potted Plant Diseases. APS Press, The American Phytopathological Society 90p.
Dixon, L. J., Schlub, R. L., Pernezny, K., and Datnoff, L. E. 2009. Host specialization and phylogenetic diversity of Corynespora cassiicola. Phytopathology 99: 1015-1027.
Farr, D.F., and Rossman, A. Y. 2016. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved August 1, 2016, from http://nt.ars-grin.gov/fungaldatabases/
Pernezny, K. L., Blazquez, C. H., Smith, L. J., and Schlub, R. L. 2014). Target spot. In, Compendium of Tomato Disease and Pests Second Edition, Edited by J. B. Jones, T. A. Zitter, T. M. Momol, and S. A. Miller. 44-46p.
Smith, L. J., and Schlub, R. L. 2005. Foliar fungi on weeds of Guam and the potential for Corynespora cassiicola as a bioherbicide for Stachytarpheta jamaicensis. (Abstr.) Phytopathology 95: S93.
USDA PCIT. 2017. USDA Phytosanitary Certificate Issuance & Tracking System. Retrieved May 23, 2018. 11:53:45 am CDT. https://pcit.aphis.usda.gov/PExD/faces/ReportHarmOrgs.jsp.
Williams, P. H. 1996. Target leaf spot. In, Compendium of Cucurbit Diseases, Ed. T. A. Zitter, D. L. Hopkins, and C. E. Thomas. APS Press, The American Phytopathological Society p 31-32.
John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.
You must be registered and logged in to post a comment. If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.
♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.
Example Comment:
Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]
♦ Posted comments will not be able to be viewed immediately.
♦ Comments may not be posted if they:
Contain inappropriate language which is not germane to the pest rating proposal;
Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;
Violates agency regulations prohibiting sexual harassment or other forms of discrimination;
Violates agency regulations prohibiting workplace violence, including threats.
♦ Comments may be edited prior to posting to ensure they are entirely germane.
♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.
Posted by ls
A pest risk assessment and rating for Grapevine pinot gris virus (GPGV) was recently requested by Joshua Kress, CDFA Pest Exclusion Branch, in response to notification received on January 24, 2018, from Foundation Plant Service (FPS), on the detection of GPGV in their Foundation grapevine plants. The risk of infestation of GPGV in California is evaluated and a permanent rating is herein proposed.
Background: Although symptoms of stunting, chlorotic mottling, and leaf deformation had been observed on V. vinifera ‘Pinot gris’, in Trentino, North Italy since 2003, it was not until 2012 that Grapevine pinot gris was first detected by deep sequencing in one symptomatic and one symptomless grapevine, Vitis vinifera cv. Pinot gris in Northern Italy. In this initial study, GPGV was associated with field symptoms of chlorotic mottling and leaf deformation, reduced yield and low quality of berries, however the plant was also associated with several other viruses and viroids. Furthermore, since GPGV was found in both symptomatic and symptomless plants from three different grape cultivars in a limited field survey, the virus could not be directly associated with the observed symptoms (Giampetruzzi et al., 2012; Glasa et al., 2014). This was further confirmed by Saldarelli et al. (2013) who reported 70% of GPGV-infected asymptomatic veins in cultivars Traminer and Pinot gris vineyards in Italy. Bianchi et al. (2015) also detected GPGV in symptomatic and asymptomatic plants over a 3-year period in a field survey of productive vineyards and scion mother plant nurseries in Italy, however, the mean quantity of the virus was significantly higher in symptomatic vines than in asymptomatic plants. Consequently, a critical level or quantity of virus could not be associated with symptom expression. Scientists in Italy determined that GPGV isolates that produce symptoms can be genetically differentiated from those that are asymptomatic (Saldarelli et al., 2015).
Grapevine pinot gris virus belongs to the genus Trichovirus in the family Betaflexiviridae. Its full-length sequence was described and shown to be phylogenetically closely related to, yet molecularly different from Grapevine berry inner necrosis virus, another Trichovirus which was found in Japan and is transmitted by eriophyid mites (Giampetruzzi et al., 2012). Since its original description in Italy, GPGV has been detected from symptomatic and asymptomatic grapevine cultivars in several countries in Europe and Asia, and few in North America, South America and Australia (see: ‘Worldwide Distribution’).
Grapevine Pinot gris virus (GPGV) was detected in California grapevine in Napa Valley and diagnosed by a testing service lab in Yolo County. An informal report of this detection was made in 2015 (Rieger, 2015) and in a ‘list of pathogens report’ submitted by a testing service lab to the CDFA. A formal first report of GPGV infecting grapevine was made in 2016 (Rwahnih et al., 2016) and marked a first detection of GPGV in the United States. In 2016, Rwahnih and other scientists at the Foundation Plant Services screened 2,014 vines, including 23 vines of Pinot gris for the possible presence and prevalence of GPGV in the collections of FPS, which are the source of all certified grapevine plants produced in California. Of all the vines tested, only one relatively rare, asymptomatic vine variety ‘Touriga Nacional” was found positive for GPGV. This vine had been imported from Portugal in 1981. The risk of GPGV spread in commercial vineyards was considered low, given the very low prevalence of the pathogen in the FPS collection, however, the need for a large-scale survey of commercial vineyards in California was emphasized, as well as, the need for research to evaluate the effect of the virus on grapevine performance and wine quality. Since cv ‘Touriga Nacional’ is rarely used in commercial vineyards, Angelini et al., (2016) molecularly surveyed 96 grapevine samples from four commercial wine grape vineyards in Napa Valley, California and reported the presence of GPGV in three cultivars, ‘Chardonnay’, ‘Cabernet Sauvignon’, and ‘Cabernet Franc’.
Grapevine pinot gris virus was recently detected in Foundation grapevine plants at FPS (see ‘Initiating Event’). Subsequently, FPS removed all source vines from the Foundation vineyard and initiated monitoring of the site with additional testing implemented to detect and destroy any further detection and contain possible spread of the pathogen (personal communication: M. Al Rwahnih, Foundation Plant Services).
Hosts: Grapevine pinot gris virus has been found in at least 28 wine and table grape varieties of Vitis vinifera and hybrids. including Pinot gris, Pinot noir, Traminer, Chardonnay, Merlot, Chardonnay, Cabernet Franc, Cabernet Sauvignon, Carmenere Glera (Prosecco), Sauvignon Blanc and Shiraz (AWRI, 2018).
Symptoms: Grapevines infected with GPGV may be symptomatic or asymptomatic. Furthermore, specific symptoms caused by GPGV have been difficult to assign as GPGV-infected grapevines were infected with other viruses. Because of this, definitive symptoms have not been attributed to GPGV alone. Symptoms putatively associated with GPGV include chlorotic mottling, leaf deformation, delayed bud-burst, stunted growth, reduced yields and low quality of berries with increased acidity (Saldarelli et al., 2015; AWRI, 2018).
Damage Potential: The complete impact of GPGV on grapevine health is currently unknown and further research is need in this area (AWRI, 2018). In Europe and Asia, GPGV and other concomitant viruses infesting grapevines have been associated with field observations of reduced yield, poor fruit set, poor quality and inner necrosis of berries (Giampetruzzi et al., 2012). In Slovenia, the disease was reported to cause considerable economic losses (Mavrič Pleško et al., 2014). Presently, the risk of spread of GPGV is considered low and the distribution of the virus has only been reported from commercial vineyards within Napa County (Al Rwahnih et al., 2016; Angelini et al., 2016).
Transmission: Grapevine Pinot gris virus is spread through movement of infected plant propagative material and by graft transmission. There is the possibility of GPGV transmission by the eriophyid mite Colomerus vitus, like the other grapevine-infecting Trichovirus, Grapevine berry inner necrosis virus, however, this has not been confirmed. Colomerus vitus commonly infests grapevine and has been reported in California.
Worldwide Distribution: Asia: China, South Korea, Georgia, Pakistan; Europe: Bosnia, Croatia, Czech Republic, France, Germany, Greece, Italy, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Turkey, Ukraine; North America: Canada, USA (California); South America: Brazil; Oceania: Australia. (Al Rwahnih et al., 2016; Angelini et al., 2016; Beuve et al., 2015; CABI, 2018; Casati et al., 2015; EPPO, 2018; Fan et al., 2016; Gazel et al., 2016; Lou et al., 2016; Mavrič Pleško et al., 2014; Rasool et al., 2017; Reynard, et al., 2016; Rius-Garcia & Olmos, 2017; Wu et al., 2017; Xiao et al., 2016).
Official Control: None reported.
California Distribution: Napa County.
California Interceptions: There are no CDFA records of detection of GPGV in quarantine shipments of plant material intercepted in California.
The risk Grapevine Pinot gris virus would pose to California is evaluated below.
1) Climate/Host Interaction: Grapevine pinot gris virus is expected to be able to establish wherever wine and table grape varieties are cultivated in California, and therefore, is likely to establish a wide spread distribution.
Evaluate if the pest would have suitable hosts and climate to establish in California.
Score: 3
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Grapevine pinot gris virus has been found in at least 28 wine and table grape varieties of Vitis vinifera and hybrids. including Pinot gris, Pinot noir, Traminer, Chardonnay, Merlot, Chardonnay, Cabernet Franc, Cabernet Sauvignon, Carmenere Glera (Prosecco), Sauvignon Blanc and Shiraz. It’s known pest host range is evaluated as very limited.
Evaluate the host range of the pest.
Score: 1
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: GPGV is transmitted artificially through grafting and infested planting stock. The involvement of a vector, an eriophyid mite Colomerus vitus, although likely, has not been confirmed. The virus has high reproduction within symptomatic and asymptomatic plants. Therefore, a ‘High’ rating is given to this category.
Evaluate the natural and artificial dispersal potential of the pest.
Score: 3
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: The economic impact of GPGV is not currently known and requires further research. This is mainly due to evidence that the virus is present in both symptomatic and symptomless grape plants, and that other viruses and viroids may be present within the same plant infested by GPGV. Nevertheless, putative symptoms of chlorotic mottling, leaf deformation, stunted growth, reduced yields and low quality of berries, have been associated with GPGV infestations. This may relate to potentially lowering crop value and yield in production. While the virus may be present in commercial vineyards of Chardonnay and Cabernet Sauvignon in California (Angelini et al., 2016), its risk of spread is considered low and its general impact on production is presently unknown. Nursery production of grapevines may be affected.
Evaluate the economic impact of the pest to California using the criteria below.
Score: A, B
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 2
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: No impact to the environment is expected.
Evaluate the environmental impact of the pest on California using the criteria below.
Environmental Impact: None
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact Score: 1
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here. (Score)
-Low = 5-8 points
–Medium = 9-12 points
-High = 13-15 points
Total points obtained on evaluation of consequences of introduction of GPGV to California = Medium (10).
6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)
-Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
Evaluation is Low (-1). Presently, Grapevine pinot gris virus has been reported only from Napa County.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)
Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 9.
Several aspects of Grapevine pinot gris virus are yet not known and require further research. In general, the impact of the virus on grape production, symptoms, prevalence and distribution within California are not fully known.
Based on the evidence provided above the proposed rating for Grapevine Pinot gris virus is B.
AWRI. 2018. Grapevine pinot gris virus. Fact Sheet, Viticulture. The Australian Wine Research Institute. Updated February 2018.
Al Rwahnih, M., D. Golino, and A. Rowhani. 2016. First report of Grapevine Pinot gris virus infecting grapevine in the United States. Plant Disease (Posted online on March 4, 2016). http://dx.doi.org/10.1094/PDIS-10-15-1235-PDN.
Angelini, E., N. Bertazzon, J. Montgomery, X. Wang, A. Zinkl, J. Stamp, and A. Wei. 2016. Occurrence of Grapevine Pinot gris virus in commercial vineyards in the United States. Plant Disease (Posted online on March 23, 2016): http://dx.doi.org/10.1094/PDIS-01-16-0055-PDN.
Beuve, M., T. Candresse, M. Tannières, and O. Lemaire. 2015. First report of Grapevine Pinot gris virus (GPGV) in grapevine in France. Plant Disease 99:293. http://dx.doi.org/10.1094/PDIS-10-14-1008-PDN.
Bianchi, G. L., F. De Amicis, L. De Sabbata, N. Di Bernardo, G. Governatori, F. Nonino, G. Prete, T. Marrazzo, S. Versolatto and C. Frausin. 2015. Occurrence of Grapevine Pinot gris virus in Friuli Venezia Giulia (Italy): Field monitoring and virus quantification by real-time RT-PCR. EPPO Bulletin 45:22-32. DOI: 10.1111/epp.12196.
Casati, P., D. Maghradze, F. Ouaglino, A. Ravasio, O. Failla and P. A. Bianco. First report of Grapevine pinot gris virus in Georgia. Journal of Plant Pathology 1 (1). DOI: 10.4454/JPP.V98I1.003
EPPO. 2018. Grapevine Pinot gris virus (GPGV00). EPPO Global Database. https://gd.eppo.int/taxon/GPGV00/distribution
Fan, X. D., Y. F. Dong, Z. P. Zhang, F. Ren, G. J. Hu, Z.N. Li, and J. Zhou. 2016. First report of Grapevine Pinot gris virus in Grapevines in China. Plant Disease 100:540. http://dx.doi.org/10.1094/PDIS-08-15-0913-PDN.
Gazel, M., K. Caǧlayan, E. Elci, and L. Ozturk. 2016. First Report of Grapevine Pinot gris virus in Grapevine in Turkey. Plant Disease 100:657. http://dx.doi.org/10.1094/PDIS-05-15-0596-PDN.
Glasa, M., L. Predajňa, P. Komínek, A. Nagyová, T. Candresse and A. Olmos. 2014. Molecular characterization of divergent grapevine Pinot gris virus isolated and their detection in Slovak and Czech grapevines. Archives of Virology 159: 2103-2107.
Giampetruzzi, A., V. Roumia, R. Roberto, U. Malossinib, N. Yoshikawac, P. La Notte, F. Terlizzi, R. Credid, and P. Saldarelli. A new grapevine virus discovered by deep sequencing of virus- and viroid-derived small RNAs in cv Pinot gris. Virus Research 163:262-268.
Lou, B. H., Y. Q. Song, A. J. Chen, X. J. Bai, B. Wang, M. Z., Wang, P. Liu and J. J. He. 2016. First report of Grapevine pinot gris virus in commercial grapevines in Southern China. Journal of Plant Pathology 98: 677-697.
Mavrič Pleško, I., M. Viršček Marn, G. Seljak, and I. Žežlina. 2014. First report of Grapevine Pinot gris virus infecting grapevine in Slovenia. Plant Disease 98:1014. http://dx.doi.org/10.1094/PDIS-11-13-1137-PDN.
Rasool, S., S. Naz, A. Rowhani, D. A. Golino, N. M. Westrick, K. D. Farrar and M. Al Rwahnih. 2017. First report of Grapevine pinot gris virus infecting grapevine in Pakistan. Plant Disease 101: 1958.
Rieger, T. 2015. New grapevine virus detected in California: Grapevine Pinot Gris Virus discussed at UCD FPS meeting. http://www.winebusiness.com/news/?go=getArticle&dataid=160912.
Reynard, J. -S, S. Schumacher, W. Menzel, J. Fuchs, P. Bohnert, M. Glasa, T. Wetzel and R. Fuchs. 2016. First report of Grapevine pinot gris virus in German vineyards. Plant Disease 100: 2545.
Ruiz-García, A. B., and A. Olmos. 2017. First report of Grapevine pinot gris virus in Grapevine in Spain. Plant Disease 101: 1070.
Saldarelli, P., A. Giampetruzzi, M. Morelli, U. Malossini, C. Pirolo, P. Bianchedi, and V. Gualandri. 2015. Genetic variability of Grapevine Pinot gris virus and its association with grapevine leaf mottling and deformation. Phytopathology 105:555-563. http://dx.doi.org/10.1094/PHYTO-09-14-0241-R.
Xiao, H., M. Shabanian, W. McFadden-Smith, and B. Meng. 2016. First report of Grapevine Pinot gris virus in commercial grapes in Canada. Plant Disease (Posted online on February 29, 2016). http://dx.doi.org/10.1094/PDIS-12-15-1405-PDN.
John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.
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Posted by ls
Fumaria muralis has been observed growing naturally in Santa Clara county in February 2018 by Italian botanist Valerio Lazzeri. This species is thought to be new to California. CDFA has not intercepted this species via any regulatory means to date and no rating has been assigned to this species. A pest rating proposal is required to assign a permanent rating.
Background:
Fumaria muralis is a sprawling annual herb that is delicate, hairless, branched and dull green in color. Its stems are weak, angular and are 10-50cm long. The leaves are finely divided down to midrib, lance to pear shaped, and form a rosette on young plants. Flowers are small, tubular and narrow with a red to pink to purple coloring and darker tips (Global Net Academy, 2018). Fumaria muralis can be distinguished from other related species by its larger flowers that have pink petals with a dirty red color at the tips. Flowering time is from June to December. It has less than 15 flowers per flowerhead and the fruit stems are erect (International Environmental Weed Foundation, 2005).
Fumaria muralis is native to Europe and north Africa (Western Australia Herbarium, 2017). It occurs commonly in crops, pastures, roadsides, home gardens and waste places (Tamar Natural Resource Management, 2015). Any soil disturbance can cause mass emergence of seedlings. Naturalized populations are found in agricultural fields but it has also been found on pond margins, in coastal dunes, on rough grounds and in dumps (Groom, 2013)
Fumaria muralis can germinate throughout the year but the main flush occurs from April to October. It grows actively from May to November. It can be difficult to control due to a persistent soil seed bank. Herbicide treatment may or may not be effective because various fumaria species can be resistant to herbicides (Western Australia Herbarium, 2017).
Worldwide Distribution:
Fumaria muralis is native in Europe and North Africa. It is widely naturalized outside its native range. Naturized populations occur in southern Australia (Western Australia Herbarium, 2017), Tasmania (Global Net Academy, 2018), and Canada (Brouillet et al. 2010)
Official Control:
Fumaria muralis has been reported as a harmful organism in Brazil and is under official control (USDA- APHIS- PCIT).
California Distribution: Fumaria muralis has been recently (February 2018) observed occurring naturally in Santa Clara county and a voucher specimen has been confirmed by a botanist in Italy, Valerio Lazzeri.
California Interceptions: Fumaria muralis has not been intercepted by CDFA through any regulatory pathways.
The risk Fumaria muralis (wall fumitory) would pose to California is evaluated below.
Consequences of Introduction:
1) Climate/Host Interaction: Fumaria muralis grows in plant hardiness zone of 5 -9 in Europe. It prefers heavy soils and high April rainfall (Murrumbidgee Catchment Management Authority, 2008). Fumaria muralis is growing naturally in limited areas of California, near habitats like creek, trails and parks. It is also likely to grow in pastures, roadsides, home gardens and waste lands. It receives a Medium (2) in this category.
Evaluate if the pest would have suitable hosts and climate to establish in California. Score:
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Fumaria muralis do not require one host but can occur where environmental conditions are favorable for its growth and establishment. It receives a High (3) in this category
Evaluate the host range of the pest.
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Fumaria reproduces seeds can remain viable in in the ground for up to 20 years. Seeds can germinate throughout the year and the plant can grow actively for half the year. Dispersal is through contaminated seed, soil movement and water runoff. Long and short range dispersal can also be aided by human and ant activity. It receives a High (3) in this category
Evaluate the natural and artificial dispersal potential of the pest.
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Fumaria muralis may compete strongly with crops, particularly cereals, vegetable and legume crops. The impacts of Fumaria sp. depends on the affected crop, time of emergence and density of infestation (Norton 2003). Fumaria species can reduce wheat yields by up to 40% and canola yields by up to 36% (Best management practices for dryland cropping systems, 2008). If this species were to establish in California, cultural practices such as cultivation, crop rotation, grazing, burning crop residues, use of competitive crops and seed cleaning would likely to be modified to reduce its growth and establishment. It receives a High (3) in this category.
Evaluate the economic impact of the pest to California using the criteria below: A, B, D
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 3
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: Fumaria muralis is not likely to lower biodiversity and change ecosystems. Fumaria spps. can be weeds of gardens, roadsides and disturbed areas and are not likely to affect endangered and threatened species in California. Because it is a likely garden weed, it could impact home and urban gardening. It receives a Medium (2) in this category.
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Score the pest for Environmental Impact. Score: 2
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here.
–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points
6) Post Entry Distribution and Survey Information: Fumaria muralis has been found occurring naturally in limited part of California but has not established fully in the state and receives a Low (-1) in this category.
Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.
–Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (12)
Fumaria muralis has been observed growing naturally but in very limited areas. Since it is like other weedy Fumaria spps, it could be more widespread than currently reported. Further sampling and examining other Fumaria specimens may reduce uncertainty regarding current distribution of this species
Fumaria muralis has been verified in California in 2018, but it has not caused any significant economic and environment impacts to the State’s agriculture and urban environment yet. However, recent credible reports indicate that is more widespread than recognized and occupies areas where other fumitory species might be expected. According to reports from Europe, it acts as other weedy species of Fumaria, so it would likely have no more impact than they do; therefore, its impacts would be modest. A “C” rating is justified.
Brouillet et al. 2010+. Fumaria muralis Sonder ex W.D.J. Koch in VASCAN, the Database of Vascular Plants of Canada. Accessed 03/05/2018: https://www.gbif.org/species/100018818
http://data.canadensys.net/vascan/taxon/29050
Cal Flora 2018. Information on wild California plants for conservation, education and appreciation. Fumaria muralis. Accessed 03/01/2018: https://www.calflora.org/entry/observ.html#srch=t&obs=parsons&cols=b
GlobalNet Academy 2018. Training and Consultancy Organization. Australia. Accessed 03/01/2018: https://www.globalnetacademy.edu.au/what-weed-is-that-fumaria/
Groom, Q. 2013. Manual of the Alien plants of Belgium. Accessed 03/16/2018: http://alienplantsbelgium.be/content/fumaria-muralis
International Environmental Weed Foundation (IEWF) 2005. Common Invasive plants in Australia. Fumaria muralis. Accessed 03/06/2018: http://www.iewf.org/weedid/Fumaria_muralis.htm
Murrumbidgee Catchment Management Authority, 2008. Best management practices for dryland cropping systems Fumaria species. New South Wales Government. Department of Primary Industries. Accessed 03/05/2018: http://archive.lls.nsw.gov.au/__data/assets/pdf_file/0007/495349/archive-fumitory.pdf
Phytosanitary Certificate Issuance & Tracking System (PCIT), Phytosanitary Export Database (PExD), USDA, APHIS. Accessed 03/01/2018: https://pcit.aphis.usda.gov/PExD/faces/ReportFormat.jsp
Tamar Natural Resource Management 2015. Tamar Valley Weed Strategy- Fumitory. Tasmania, Australia. Accessed 03/06/2018: http://www.weeds.asn.au/tasmanian-weeds/view-by-common-name/fumitory/
Western Australia Herbarium 2017. Flora base-The Western Australia Flora 2017. Accessed 03/01/2018: https://florabase.dpaw.wa.gov.au/browse/profile/2971
Raj Randhawa, 1220 ‘N’ Street, Room 221, Sacramento CA 95814, (916) 654-0317, plant.health[@]cdfa.ca.gov
Dean G. Kelch, Primary Botanist; California Department of Food and Agriculture; 1220 N Street, Sacramento, CA 95814; Tel. (916) 403-6650; plant.health[@]cdfa.ca.gov.
Updated on 7/11/2019 by ls
Hypothenemus eruditus is currently Q-rated. A permanent pest rating proposal is required to support an official pest rating.
Background: This tiny (1-1.2 mm in length) bark beetle is one of the most widely-distributed and variable species in the genus Hypothenemus (Bright and Stark, 1973). The beetle has been reported to feed on hundreds of species of plants and other materials as well, including fungus and even the cover of a book (evidently the reason for the choice of the name eruditus) (Huang, 2016; Turner and Beaver, 2015; Wood, 1982). In plants, it is reported to feed in dying twigs and branches (Bright and Stark, 1973). Females mate with their flightless male siblings before leaving the gallery. Hypothenemus eruditus does not appear to cause any recognized economic or environmental impact (Huang, 2016; Turner and Beaver, 2015). Recent work suggest that there may be multiple (>10) cryptic species that are currently identified as Hypothenemus eruditus; this is perhaps not surprising, given the many synonyms listed for it, its minute size, and its morphological variability (Huang, 2016; Kirkendall and Jordal, 2006).
Worldwide Distribution: Hypothenemus eruditus is widely distributed. The species occurs in Europe, Asia, Africa, Australia, North America, Central America, and South America. In the United States, it occurs in the eastern United States and in California (Bright and Stark, 1973; Wood, 1982.
Official Control: Hypothenemus eruditus is not known to be under any official control.
California Distribution: Hypothenemus eruditus has been reported from Los Angeles, Orange, San Diego, and Santa Barbara counties. Records representing collections exclusive of nurseries were found for the following localities: Santa Barbara County: Arroyo Hondo Preserve (2002); Santa Rosa Island, Cherry Canyon, Torrey pines grove, and Windmill Canyon (2008); San Diego County: Santee (2012) (PDR# 1316740) (Bright and Stark, 1973; CDFA Pest and Damage Record; Symbiota Collections of Arthropods Network).
California Interceptions: Hypothenemus eruditus has been intercepted twice on shipments entering California: Once on dried twigs from Laos (PDR# 050455) and once on Polyscias fruticosa from Florida (PDR# 063283). As mentioned above, this beetle was also found on avocado in a residential garden in Santee, San Diego County, California (PDR# 1316740).
The risk Hypothenemus eruditus would pose to California is evaluated below.
1) Climate/Host Interaction: Hypothenemus eruditus occurs widely in the United States. The species occurs in California and on the east coast, from New Hampshire to Florida and west to Illinois and Texas. This suggests that eruditus could become established over a significant portion of California. The list of hosts includes hundreds of species of plants and fungi. Therefore, it receives a High (3) in this category.
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Hypothenemus eruditus is known to feed on hundreds of species of plants, as well as fungi. Therefore, it receives a High (3) in this category.
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Hypothenemus eruditus is capable of sustained flight. Females mate with their flightless male siblings, so they leave their development site ready to colonize new host material (Huang, 2016). The beetle can also be transported in wood and wood products. Therefore, it receives a High (3) in this category.
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Hypothenemus eruditus is not known to be an economically-significant pest (Huang, 2016). The species already occurs in California and the eastern United States and it has a widespread world distribution. However, no reports have been found suggesting that it has an economic impact. However, there is the possibility that other species, including cryptic ones, could be identified at eruditus. Such species could pose a threat to California agriculture, for example, lowering crop yield and increasing crop production costs. Therefore, it receives a Medium (2) in this category.
Economic Impact: A, B
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: Medium (2)
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: Hypothenemus eruditus is not known to have an environmental impact anywhere. The beetle already occurs in California and the eastern United States and no reports were found of it having an environmental impact. However, this could reflect a lack of research rather than a lack of impact. In addition, there is the possibility that other species of Hypothenemus, including cryptic ones, could be identified at eruditus. Such species could pose a threat to the environment, for example, by disrupting natural communities. Therefore, it receives a Medium (2) in this category.
Evaluate the environmental impact of the pest on California using the criteria below.
Environmental Impact: A
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact Score: Medium (2)
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here.
–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points
6) Post Entry Distribution and Survey Information: Although this species is likely present in additional areas of California, Hypothenemus eruditus has been reported from outdoor, non-nursery localities in Santa Barbara and San Diego Counties. It receives a Low (-1) in this category.
–Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (12)
The most significant uncertainty regarding Hypothenemus eruditus is the species identity itself. There is evidence that there are actually multiple (>10) species that are currently recognized as H. eruditus. There is a risk that a species with biological characteristics differing from those considered for H. eruditus could be intercepted and not be regulated because it is identified as that species. Such a cryptic species could have greater (than is recognized for H. eruditus) potential for economic and/or environmental impact. Systematic research on Hypothenemus is needed. There is also a significant likelihood that H. eruditus is more widespread in California than is currently known. It is a tiny beetle and is not easy to identify.
Hypothenemus eruditus is widely distributed and is not known to have any economic or environmental impacts. However, there is evidence that multiple cryptic species of Hypothenemus may be currently identified as H. eruditus. A cautious approach has been taken and a “B” rating is justified.
Bright Jr., D.E. and R.W. Stark. 1973. The Bark and Ambrosia Beetles of California. University of California Press. 169 pp.
Huang, Y.T. 2016. Featured creatures: Hypothenemus eruditus Westwood. University of Florida. http://entnemdept.ufl.edu/creatures/trees/beetles/Hypothenemus_eruditus.htm
Kirkendall, L. R. and B.H. Jordal. 2006. The bark and ambrosia beetles (Curculionidae, Scolytinae) of Cocos Island, Costa Rica and the role of mating systems in island zoogeography. Biological Journal of the Linnean Society. 89: 729-743.
Symbiota Collections of Arthropods Network. Accessed 5 February 2018. http://scan1.acis.ufl.edu
Turner, C.R. and R.A. Beaver. 2015. Hypothenemus eruditus Westwood and Hypothenemus seriatus (Eichhoff) (Curculionidae: Scolytinae: Cryphalini) in Britain. The Coleopterist. 24(1): 12-15.
Wood, S.L. 1982. The bark and ambrosia beetles of North and Central America (Coleoptera: Scolytidae), a taxonomic monograph. Great Basin Naturalist Memoirs. 6: 1-1356.
Kyle Beucke, 1220 N Street, Room 221, Sacramento, CA, 95814, 916-403-6741; plant.health[@]cdfa.ca.gov.
Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov
4/25/18 – 6/9/18
You must be registered and logged in to post a comment. If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.
♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.
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Posted by ls
August 26, 2014, Dr. Gillian Watson identified Maconellicoccus hirsutus from a sample collected on 100 heavily infested silk oak trees at a golf course in Rancho Mirage, Riverside County. The mealybug was previously eradicated from Riverside County in 2011. Follow-up surveys have revealed that the pest is now widespread and abundant in Riverside County. An updated pest rating proposal is needed to determine future direction.
Background: Maconellicoccus hirsutus is a highly polyphagous mealybug that feeds on the stems, leaves, buds, fruit, and roots of plants in more than 200 genera in 77 plant families1,2. Economically important hosts include grapes, citrus, avocado, cotton, Prunus spp., Solanum spp., and ornamentals. While feeding, the mealybug injects toxic saliva into plants that inhibits cell enlargement, causing stunting of new growth and curling and contortion of leaves7. Entire plants may be stunted and deformed7. High populations can lead to the death of plants7. The mealybug can spread long distances through the trade in host plants and fruit.
Worldwide Distribution: Maconellicoccus hirsutus is considered to be native to southern Asia1,2 and has invaded much of the Caribbean, Africa, Asia, Australia, Oceania, and South America. In North America it has been found in Mexico, Florida, Georgia, Louisiana, Texas, and Imperial and Riverside counties, California3. It has recently been detected and is under eradication in Tennessee6.
Official Control: Maconellicoccus hirsutus is listed as a quarantine pest by many nations including Antigua and Barbuda4, Bermuda4, Brazil4, Cayman Islands4, Chile4, Colombia4, Costa Rica4, Ecuador4, El Salvador4, Guatemala4, Honduras4, Israel4, Jamaica4, Japan4, Republic of Korea4, Mexico4, Morocco4, Nicaragua4, Panama4, Paraguay4, Peru4, South Africa4, Turkey4, Uruguay4, and the European Union2.
California Distribution: Maconellicoccus hirsutus has been present in Imperial County since 1999. The mealybug was detected in Riverside County in 2011 and successfully eradicated by the county. The mealybug was detected again in Riverside County in 2014 infesting 100 silk oak trees at a golf course.
California Interceptions: Maconellicoccus hirsutus is occasionally intercepted on fruit or plants headed for destinations within California, most often on longan fruits.
The risk Maconellicoccus hirsutus (pink hibiscus mealybug) would pose to California is evaluated below.
Consequences of Introduction:
1) Climate/Host Interaction: Maconellicoccus hirsutus, due to its polyphagous nature, is likely to encounter suitable hosts throughout California. The present distribution of the mealybug corresponds to USDA plant hardiness zones 9-131, which encompasses much of California. Pink hibiscus mealybug receives a High (3) in this category.
Evaluate if the pest would have suitable hosts and climate to establish in California. Score:
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Maconellicoccus hirsutus is known to feed on plants in more than 200 genera in 77 plant families. The mealybug receives a High(3) in this category.
Evaluate the host range of the pest. Score:
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Pink hibiscus mealybug has a high reproductive rate. Each female lays 150-600 eggs and there can be up to 15 generations per year2. The crawlers of this mealybug are reported to be very active and are capable of spreading to nearby plants; furthermore, they may be dispersed by wind or by hitchhiking on clothing, equipment, or animals. The mealybugs may also be spread long distances through the movement of infested plants or fruit. Maconellicoccus hirsutus receives a High (3) in this category.
Evaluate the natural and artificial dispersal potential of the pest. Score:
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Maconellicoccus hirsutus has been present in Imperial County since 1999, where it has been successfully controlled by biological control agents. No economic damages in California are presently attributed to this pest. In the presence of effective biological control, the mealybug is not expected to lower crop yields. In the absence of effective biological control, yields are likely to be reduced (see uncertainty section below). As it feeds on a wide variety of ornamentals, the mealybug may increase crop production costs in nurseries by triggering new chemical treatments to ensure clean nursery stock. The mealybug is listed as a quarantine pest by many nations and its presence is likely to disrupt markets for California fresh fruit. Pink hibiscus mealybug is not expected change cultural practices, vector pestiferous organisms, injure agriculturally important animals, or interfere with the delivery or supply of water for agricultural uses. Maconellicoccus hirsutus receives a Medium (2) in this category.
Evaluate the economic impact of the pest to California using the criteria below. Score:
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: Maconellicoccus hirsutus is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. Algodones Dunes sunflower (Helianthus niveus tephrodes), Bakersfield cactus (Opuntia basilaris var. treleasei), and small-leaved rose (Rosa minutifolia) are listed as threatened or endangered plants in California and are potential hosts of this mealybug. An infestation of the mealybug in Riverside County in 2011 was eradicated by the county, indicating that the presence of this pest may trigger additional official treatment programs. Additional treatments are also likely in the nursery industry and by residents who find infested plants unsightly. In some cases, the mealybug is likely to be managed by biological control programs such that it does not significantly impact cultural practices, home/urban gardening, or ornamental plantings. However, due to its extremely high reproductive rate and broad host range it is likely to sometimes cause significant damage to ornamental plants as it encounters them before biological control agents. Maconellicoccus hirsutus receives a High (3) in this category.
Evaluate the environmental impact of the pest on California using the criteria below.
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Score the pest for Environmental Impact. Score: 3
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here.
–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points
6) Post Entry Distribution and Survey Information: Maconellicoccus hirsutus is only known to be established in Imperial and Riverside counties. The mealybug receives a Low (-1) in this category.
Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.
–Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
The final score is the consequences of introduction score minus the post entry distribution and survey information score: High(13)
There have been no recent statewide surveys for the mealybug, so it may have a larger distribution within California. In the absence of surveys or official control, trading partners are likely to regulate the entire state, so range expansions of pink hibiscus mealybug may not trigger new impacts on fruit exports. Pheidole megacephala (bigheaded ant) has recently been detected in California. This is an aggressive ant that is likely to tend pink hibiscus mealybug and consume all parasites and predators it encounters, reducing the effectiveness of biological control5. As bigheaded ant expands its range through southern California it is likely to facilitate the invasion of Maconellicoccus hirsutus and may disrupt the presently successful biological control program. If this were to occur, yield of economically important crops such as almonds, peaches, pistachios, walnuts, olives, and citrus may be reduced. Crop quality and production costs by increase in the long term. This may elevate the economic impact of the pest to High (3).
Maconellicoccus hirsutus is a highly polyphagous mealybug with a limited distribution within California at present. If it enters commercial fruit groves and vineyards the presence of the mealybug is likely to close or restrict export markets for fresh fruit. If found outside of its present distribution, it will likely trigger treatment or biological control programs. Although pink hibiscus mealybug has been known to be present in California since 1999 it remains under official active management programs including survey and biological control. The “A” rating is supported while these remain in effect.
1Culliney, T.W. 2014. Deregulation Evaluation of Established Pests (DEEP); DEEP Report on Maconellicoccus hirsutus (Green): Egyptian hibiscus mealybug, pink hibiscus mealybug.
2Data sheets on quarantine pests: Maconellicoccus hirsutus. 2005. European and Mediterranean Plant Protection Organization. OEPP/EPPO Bulletin 35, 413-415. http://www.eppo.int/QUARANTINE/insects/Maconellicoccus_hirsutus/DS_Maconellicoccus_hirsutus.pdf
3Ben-Dov, Y. 2014. ScaleNet, Maconellicoccus hirsutus. Available online at http://www.sel.barc.usda.gov/catalogs/pseudoco/Maconellicoccushirsutus.htm Accessed on 9 April 2014.
4USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/
5Buckley, Ralf and Penny Gullan. 1991. More aggressive ant species (Hymenoptera: Formicidae) provide better protection for soft scales and mealybugs (Homoptera: Coccidae, Pseudococcidae). Biotropica 23(3): 282-286. http://www.jstor.org/discover/10.2307/2388205?uid=3739560&uid=2&uid=4&uid=3739256&sid=21104122016081
6NAPIS; Email updated dated September 2, 2014. http://pest.ceris.purdue.edu/capsreview.php?code=IRAWBIA
7Hoy, Marjorie A., Avas Hamon, and Ru Nguyen. 2006. Common name: pink hibiscus mealybug. University of Florida Featured Creatures. http://entnemdept.ufl.edu/creatures/orn/mealybug/mealybug.htm
Jason Leathers, 2800 Gateway Oaks, Sacramento CA 95833, (916) 654-1211, plant.health[@]cdfa.ca.gov
4/25/18 – 6/9/18
You must be registered and logged in to post a comment. If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.
♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.
Example Comment:
Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]
♦ Posted comments will not be able to be viewed immediately.
♦ Comments may not be posted if they:
Contain inappropriate language which is not germane to the pest rating proposal;
Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;
Violates agency regulations prohibiting sexual harassment or other forms of discrimination;
Violates agency regulations prohibiting workplace violence, including threats.
♦ Comments may be edited prior to posting to ensure they are entirely germane.
♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.
Posted by ls
On October 12, 2017, the California Dog Team a shipment of nuts of Castanea sativa (European chestnut) at a parcel distribution facility in Alameda County. The shipment had originated in Indiana and was destined to a private citizen in Contra Costa County. A sample of nuts were collected by Alameda County Agricultural officials, and sent to the CDFA Plant Diagnostics Branch for Diagnosis. Suzanne Latham, CDFA plant pathologist detected the pathogen, Colletotrichum henanense in culture from the nuts. The identity of the associated pathogen was later confirmed by USDA National Identification Services at Beltsville, Maryland, and marked the first domestic detection of C. henanense in the USA. Consequent to the California detection, all infected plant materials were destroyed. The risk of infestation of C. henanense in California is evaluated and a permanent rating is proposed.
Background: Colletotrichum henanense is a distinct fungus species belonging to the vastly morphological and physiological variable C. gloeosporioides and is genetically identified from other species of the complex. The species was originally described in 2015 from tea plants (Camelia sinensis) and Japanese thistle (Cirsium japonicum) in Xinyang, Henan Province, and Beijing, China respectively (Liu et al., 2015). The pathogen causes anthracnose disease in its host plants. Camellia species were affected by anthracnose disease in China where the plant species are used as in production of edible oil, processed tea and as ornamentals (Li et al., 2018; Liu et al., 2015). The pathogen has only been reported from China until its 2017 detection in the California.
Symptoms: Generally, Colletotrichum-infected host plants exhibit symptoms of anthracnose which include dark brown leaf, stem and fruit spots and wilting of leaves which often result in dieback and reduction in plant quality.
Hosts: Camellia sinensis (tea tree), C. oleifera (tea-oil tree. Theaceae); Cirsium japonicum (Japanese thistle. Asteraceae) (De Silva et al., 2017; Li et al., 2018; Liu et al., 2015). The detection of Colletotrichum henanense in Castanea sativa (European chestnut) is included here (see: Initiating Event).
Symptoms: Colletotrichum henanense causes leaf spot symptoms. Leaf spots or lesions in tea-oil tree are semicircular or half-oval, brown to black with greyish-white centers. Severely infected leaves wither and drop (Li et al., 2018).
Disease Cycle: It is likely that Colletotrichum henanense has a similar life cycle to that of other Colletotrichum species and survives between crops during winter as mycelium on plant residue in soil, on infected plants, and on seeds. During active growth, the pathogen produces masses of hyphae (stromata) which bear conidiophores, on the plant surface. Conidia (spores) are produced at the tips of the conidiophores and disseminated by wind, rain, cultivation tools, equipment, and field workers. Conidia are transmitted to host plants. Humid, wet, rainy weather is necessary for infection to occur. These requirements may limit the occurrence of the pathogen in California fields and subsequently, the pathogen may be more of a problem under controlled environments of greenhouses. Conidia germinate, penetrate host tissue by means of specialized hyphae (appresoria) and invade host tissue.
Transmission: Wind, wind-driven rain, cultivation tools, and human contact.
Damage Potential: In China, 40% of tea-oil tree yield loss has been suggested (Li et al., 2018). A 42.5% incidence of anthracnose disease caused by C. henanense was observed in 85 of 200 young tea-oil plants grown in a nursery in Kunming, Yunnan Province, China (Li et al., 2018). Generally, anthracnose disease can result in reduced plant quality and growth, and marketability. Nursery productions of Camellia and chestnut are particularly at risk as nursery conditions are often conducive to infection by Colletotrichum species. In open fields, disease development may be sporadic as it is affected by levels of pathogen inoculum and environmental conditions.
Worldwide Distribution: Asia: China; North America: USA (De Silva et al., 2017; Li et al., 2018; Liu et al., 2015).
Official Control: None reported.
California Distribution: Colletotrichum henanense is not established in California (see “Initiating Event”).
California Interceptions: The risk Colletotrichum henanense would pose to California is evaluated below.
1) Climate/Host Interaction: Like other species of Colletotrichum henanense requires humid, wet, rainy weather for conidia to infect host plants. This environmental requirement and narrow host range may limit the ability of the pathogen to fully establish and spread under dry field conditions.
Evaluate if the pest would have suitable hosts and climate to establish in California.
Score: 2
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: Presently, the host range is limited to Camellia sinensis, C. oleifera, Cirsium japonicum, and Castanea sativa.
Evaluate the host range of the pest.
Score: 1
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Colletotrichum henanense has high reproductive potential and conidia are produced successively. They are transmitted by wind, wind-driven rain, cultivation tools, and human contact, however, conidial germination and plant infection require long, wet periods.
Evaluate the natural and artificial dispersal potential of the pest.
Score: 3
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Anthracnose-infected chestnut and camellia plants may result in lower crop value and market loss. Nursery productions of Camellia and chestnut are particularly at risk as nursery conditions are often conducive to infection by Colletotrichum In open fields, disease development may be sporadic as it is affected by levels of pathogen inoculum and environmental conditions. Its economic impact is evaluated as a Medium risk.
Evaluate the economic impact of the pest to California using the criteria below.
Score: B, C
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 2
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: Chestnut trees cultivated and growing in open environments in California are not expected to be significantly affected by Colletotrichum henanense due to the high moisture conditions required for the development of the pathogen. However, under humid and moist environments, the pathogen may be more of a problem particularly in ornamental plantings of Camellia in home/urban and private/public settings.
Evaluate the environmental impact of the pest on California using the criteria below.
Environmental Impact: E
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact Score: 2
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here.
-Low = 5-8 points
–Medium = 9-12 points
-High = 13-15 points
6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.
Evaluation is ‘Not Established’
Score (0). Colletotrichum henanense is not known to be established in California and is known only from its detected in an intercepted shipment of chestnut.
–Not established (0) Pest never detected in California, or known only from incursions.
-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)
Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 10.
None.
Based on the evidence provided above the proposed rating for the anthracnose pathogen, Colletotrichum henanense, is B.
De Silva, D. D., P. K. Ades, P. W. Crous and P. W. J. Taylor. 2017. Colletotrichum species associated with chili anthracnose in Australia. Plant Pathology 66 (2): 254-267.
Farr, D. F., and A. Y. Rossman. Fungal Databases, U.S. National Fungus Collections, ARS, USDA. Retrieved March 16, 2018, from https://nt.ars-grin.gov/fungaldatabases/
Li, H., G. Y. Zhou, X. Y. Qi and S. Q. Jiang. 2018. First report of Colletotrichum henanense causing anthracnose on tea-oil trees in China. Plant Disease “First Look” paper, accepted for publication, posted 01/03/2018. https://doi.org/10.1094/PDIS-08-17-1302-PDN
Liu, F., Weir, B.S., Damm, U., Crous, P.W., Wang, Y., Liu, B., Wang, M., Zhang, M., and Cai, L. 2015. Unravelling Colletotrichum species associated with Camellia: employing ApMat and GS loci to resolve species in the C. gloeosporioides complex. Persoonia 35: 63-86.
John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.
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Posted by ls
On February 26, 2018, Dr. G. Vidalakis, University of California, Director, Citrus Clonal Protection Program, informed CDFA of his detection of Citrus leaf blotch virus (CLBV) from a Bearss Lime tree at a residence in Los Angeles County. Subsequently, an official sample, which comprised a total of 4 subsamples, was collected by the CDFA from the same Bearss Lime tree and sent to the CDFA Plant Pathology Laboratory for diagnosis. On February 27, 2018, Tongyan Tian, CDFA Plant Pathologist, detected Citrus leaf blotch virus from all four subsamples using RT-qPCR and further confirmed the identity of the pathogen by conventional RT-PCR and sequencing. A temporary Q rating was assigned to the pathogen. The status, risk and consequences of introduction of CLBV to California are assessed and a pest permanent pest rating is proposed herein.
Background: In 1968, Dweet mottle virus (DMV) was initially detected and reported from Riverside, California, during re-indexing of a candidate Cleopatra mandarin variety (C. reticulata) on ‘Dweet’ tangor at the University of California Riverside Citrus Variety Improvement Program, the forerunner of the present Citrus Clonal Protection Program (CCPP). The candidate mandarin variety had been introduced from Florida into the Program at Riverside. The virus produced leaf chlorotic blotching symptoms that resembled, but were distinct from, symptoms produced by psorosis virus and Citrus concave gum virus. It also produced a mild exocortis reaction in Etrog citron. The parent tree did not show symptoms of damage caused by any known virus and the trunk appeared normal without any signs of stem pitting or bark discoloration, although small fruit, twig dieback and little new growth were apparent. Since the virus produced symptoms only in ‘Dweet’, it was named Dweet mottle virus (Roistacher & Blue, 1968). However, Dweet mottle virus was not reported from any commercial citrus production sites nor was it observed to produce any economic losses and was detected only once after 1963 in the CCPP indexing program (Krueger et al., 2012).
Then in 1984, at the Citrus Variety Improvement Program in Spain, Navarro and other scientists reported a new graft transmissible disease that caused a bud-union incompatibility between ‘Nagami’ kumquat and ‘Troyer’ citrange rootstock. The ‘Nagami’ kumquat had been introduced from Corsica, France. In addition to bud-union incompatibility, the presumptive virus involved caused vein clearing in certain citrus species and stem pitting in Etrog citron. However, after shoot-tip grafting, some plants produced were compatible with Troyer, but still caused stem pitting in Etrog citron, thereby, indicating the involvement of more than one virus (Navarro et al., 1984). Galipienso et al., 2000, gave further evidence of the involvement of more than one virus by demonstrating bud union crease in certain citrus species but not others when propagated on ‘Troyer’ citrange. However, chlorotic blotching in ‘Dweet’ tangor, like those induced by DMV, and stem pitting in Etrog citron were produced by all sources of the virus. In 2001-02, the causal agent in “Nagami’ kumquat was partially purified and characterized and given the candidate name, Citrus leaf blotch virus (CLBV) (Galipienso et al., 2001; Vives et al., 2001, 2002). Furthermore, these researchers detected CLBV in different citrus varieties from Japan, New South Wales (Australia), Spain, and Florida, usually associated with abnormal bud union on citrange or citrumelo. Comparison of 14 CLBV isolates from Spain, Japan, USA, France and Australia showed low genetic diversity (Vives et al., 2002). Low rates of seed transmission were demonstrated in three citrus varieties or hybrids (Guerri et al., 2004). A few years later, Vives et al., (2005) conducted partial sequence analysis to show that Dweet mottle virus from California had over 96% sequence (high) homology with citrus leaf blotch virus from Spain and therefore, suggested that DMV may be caused by CLBV. Both viruses induce mottling in ‘Dweet’ tangor and stem pitting in ‘Etrog’ citron and that, besides CLBV, a different pathogen causing bud-union crease and vein clearing may be present in ‘Nagami’ kumquat sources but not in DMV from California source. This was further demonstrated by Vives et al., (2008a) by the development of full-genome cDNA clones of CLBV that caused systemic infection in agro-inoculated herbaceous and citrus host plants and induced chlorotic blotching in ‘Dweet’ tangor and stem pitting in Etrog citron, but not vein clearing in Pineapple sweet orange or bud union crease on trifoliate rootstocks. Then in 2010, Hajeri and other researchers at the University of California, Riverside, and the USDA ARS National Clonal Germplasm Repository for Citrus and Dates (NCGRCD), Riverside, determined the complete nucleotide sequence of DMV and with phylogenetic analysis showed that DMV is an isolate of CLBV, and not a distinct species, within the genus Citrivirus.
In California, the seed transmissibility of citrus leaf blotch virus caused concern to the citrus nursery industry. Consequently, Kreuger et al. (2012) reported that all citrus trees at CCPP and NCGRCD were tested for the presence of the virus using RT-PCR with local DMV positives and a CLBV positive from Florida as positive controls. The virus was not detected in the tested trees. Furthermore, they failed to detect it during surveys of field trees exhibiting bud union abnormalities for the presence of specific pathogens and therefore, while the overall status of CLBV in California is presently unknown, they believe that this virus if present at all, is only at a low incidence. This is because the close identity of CLBV and DMV has likely prevented CLBV from becoming introduced into California. All introductions of new citrus germplasm are indexed into ‘Dweet’ tangor as well as other indicator species at CCPP and NCGRCD. Reaction of CLBV in ‘Dweet’ tangor would enable detection of this virus, even if the actual identity of the virus was not known at the time of indexing. Detection of positives or even misidentifications would have been eliminated by thermal therapy or shoot-tip grafting before release (Kreuger et al., 2005, 2012).
Citrus leaf blotch virus has been reported in China, Corsica (France), Cuba, Italy, Japan, New South Wales (Australia), New Zealand, Spain, Florida, Arkansas, Oregon, and California (USA). In Arkansas and Oregon, the virus was found in peony plants showing stunting and gnarled irregularities, however, since the virus was found in both symptomatic and asymptomatic material, it could not be associated with the disease and its role in peony health is currently unknown. Nonetheless, CLBV may easily move between propagation cycles via mechanical and seed transmission of clonally propagated peony plants (Gress et al., 2017).
Citrus leaf blotch virus not only causes symptomless infection in most citrus but also, is unevenly distributed within an infected plant, thereby presenting a possible challenge for its detection. In greenhouse studies, Vives et al. (2002) detected CLBV consistently in young leaves of infected ‘Nagami’ kumquat, ‘Owari’ Satsuma, Navelina and Navel oranges, however, detection in old leaves of other citrus species (Eureka lemon, Marsh grapefruit and Nules Clementine) was not consistent, particularly in Pineapple sweet orange. Detection of the virus in field trees was even less consistent, and not detected in neighbor trees showing similar symptoms possibly due to low titer or uneven distribution of the virus in the plant.
Hosts: Citrus spp., including C. sinensis, C. limon, C. unshiu, C. paradisi, Poncirus trifoliata, P. trifoliata x C. sinensis (Harper et al., 2008), C. medica (Etrog citrus), C. reticulata x C. sinensis (‘Dweet’ tangor) (Roistacher & Blue, 1968), Fortunella margarita (kumquat “Nagami’) (Navarro et al., 1984), Prunus avium cv. Red-lamp (sweet cherry) (Wang et al., 2016), Actinidia sp. (kiwifruit) (Zhu et al., 2016), Paeonia lactiflora (peony) (Gress et al., 2017). Experimental hosts include Nicotiana cavicola (Guardo et al., 2009), N. occidentalis and N. benthamiana (Vives et al., 2008b).
Symptoms: Citrus leaf blotch virus causes symptomless infection in most citrus species and cultivars (Vives et al., 2008a). However, CLBV (and the isolate, DMV) induce chlorotic blotching or mottling in ‘Dweet’ tangor and stem pitting ‘Etrog’ citron. Although CLBV does not induce bud union crease on trifoliate rootstock (Vives et al., 2008a), it has been found to be usually associated with abnormal bud union on citrange or citrumelo rootstock. A different pathogen or interaction of CLBV with a different pathogen is likely the cause of bud union crease and vein clearing symptoms (Vives et al., 2005).
Damage Potential: Citrus leaf blotch virus causes chlorotic leaf blotching in ‘Dweet’ tangor and stem pitting in Etrog citron. Although it does not induce bud union crease in several citrus species it is usually associated with bud union crease symptoms in citrange and citrumelo rootstocks and therefore, an interaction between CLBV and other agent(s) cannot be ruled out. There are no reports of yield losses due to CLBV and the virus can cause symptomless infections in most citrus species and cultivars. In California, CLBV (aka DMV) is a regulated pathogen and its distribution is unknown or at best likely to be of low incidence. CLBV (aka DMV) was not reported from any commercial citrus production sites in California nor was it observed to produce any economic losses (Krueger et al., 2012). However, in certain scion-rootstock combinations using ‘Dweet’ tangor and Etrog citron rootstocks there may be a potential for disease development due to CLBV.
Transmission: Citrus leaf blotch virus is transmitted in citrus by grafting and seed. CLBV dispersal occurs primarily by propagation of infected buds. Low rates of seed transmission in at least three citrus species and hybrid, ‘Troyer’ citrange (Citrus sinensis x Poncirus trifoliata), ‘Nagami’ kumquat (Fortunella margarita) and sour orange (C. aurantium), has been demonstrated (Guerri et al., 2004). Also, CLBV has been mechanically transmitted to Nicotiana cavicola (Guardo et al., 2009), by sap inoculation to N. occidentalis and N. benthamiana (Vives et al., 2008b), and transmitted from citrus to citrus by contaminated knife blades (Roistacher et al., 1980). The virus is not transmitted by vectors (Galipienso et al., 2000).
Worldwide Distribution: Asia: China, Japan; Europe: Italy, Spain; North America: USA, Cuba; Oceania: New South Wales (Australia), New Zealand (Cao et al., 2017; Gress et al., 2017; Guardo et al., 2007; Harper et al., 2008; Hernández-Rodríguez, 2016; Navarro et al., 1984; Roistacher & Blue, 1968; Vives et al., 2002; Wang et al., 2016).
Official Control: Citrus leaf blotch virus is on the ‘Harmful Organism’ list for Uruguay (USDA PCIT, 2018). CLBV (aka DMV) is a regulated pathogen in California’s mandatory Citrus Nursery Stock Pest Cleanliness Program (CCR, Title 3, Division 4, Chapter 4, Subchapter 6, Section 3701).
California Distribution: The distribution in California is unknown. If at all present, it is likely to be only at a low incidence (Kreuger et al., 2005, 2012. See: ‘Background’).
California Interceptions: No official interceptions have been reported.
The risk Citrus leaf blotch virus would pose to California is evaluated below.
1) Climate/Host Interaction: Although the distribution of Citrus leaf blotch virus in California, is presently unknown and is likely to be only at a low incidence (Kreuger et al., 2012), if not regulated, it may be possible for the pathogen to have a widespread establishment in symptomatic and non-symptomatic infected citrus varieties in commercial citrus-growing regions of the State.
Evaluate if the pest would have suitable hosts and climate to establish in California. Score: 3
– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.
2) Known Pest Host Range: The natural host range is limited primarily to Citrus Other hosts include sweet cherry and kiwifruit reported from China and peony reported from Arkansas and Oregon. Experimental hosts include, Nicotiana cavicola, N. occidentalis and N. benthamiana.
Evaluate the host range of the pest.
Score: 1
– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.
3) Pest Dispersal Potential: Citrus leaf blotch virus has high reproduction within its plant host, although unevenly distributed within infected plants. It is transmitted by grafting, seed, and mechanically. Its ability for long distance spread through infected seed render it a high rating for dispersal.
Evaluate the natural and artificial dispersal potential of the pest.
Score: 3
– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.
4) Economic Impact: Citrus leaf blotch virus is a regulated pathogen under California’s mandatory Citrus Nursery Stock Pest Cleanliness Program. Under this program any citrus stock found positive for the pathogen would be eliminated before release for commercial planting. This pathogen causes chlorotic leaf blotching in ‘Dweet’ tangor and stem pitting in Etrog citron. Although it does not induce bud union crease in several citrus species, it is usually associated with bud union crease symptoms in citrange and citrumelo rootstocks and therefore, an interaction between CLBV and other agent(s) cannot be ruled out. There are no reports of yield losses due to CLBV and the virus can cause symptomless infections in most citrus species and cultivars. Researchers have stated that CLBV has not been reported from commercial citrus production sites in California nor was it observed to cause any economic losses. If citrus stock were not regulated, it is likely that in certain scion-rootstock combinations using ‘Dweet’ tangor and Etrog citron rootstocks there may be a potential for disease development due to CLBV. In such a case, it is estimated that CLBV could lower crop yield and value and trigger the loss of markets.
Evaluate the economic impact of the pest to California using the criteria below.
Economic Impact: A, B, C
A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.
Economic Impact Score: 3
– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.
5) Environmental Impact: No environmental impact is expected, however, if not regulated, CLBV may impact home/urban plantings of citrus host plants.
Evaluate the environmental impact of the pest on California using the criteria below.
Environmental Impact: E
A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.
Environmental Impact. Score: 2
– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.
Add up the total score and include it here. (Score)
-Low = 5-8 points
–Medium = 9-12 points
-High = 13-15 points
6) Post Entry Distribution and Survey Information: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)
Evaluation is (0). While the distribution of CLBV in California is currently not known, there is no evidence that it is established within the State.
–Not established (0) Pest never detected in California, or known only from incursions.
-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
-High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.
7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: (Score)
Final Score: Score of Consequences of Introduction – Score of Post Entry Distribution and Survey Information = 12
The in-state distribution of CLBV is not currently known. Also, the impact of infection related to crop damage and losses is not known.
Based on the evidence provided above the proposed rating for Citrus leaf blotch virus is B.
Cao, M. J., Y. -Q. Yu, X. Tian, F. Y. Y. and, R. H. Li and C. Y. Zhou. 2017. First report of Citrus leaf blotch in lemon in China. Plant Disease 101: 8. https://doi.org/10.1094/PDIS-10-16-1500-PDN
Galipienso, L., L. Navarro, J. F. Ballester-Olmos, J. Pina, P. Moreno, and J. Guerri. 2000. Host range and symptomatology of a graft transmissible pathogen causing bud union crease of citrus on trifoliate rootstocks. Plant Pathology 49: 308–314.
Galipienso, L., M. C. Vives, P. Moreno, R. G. Milne, L. Navarro and J. Guerri. 2001. Partial characterization of Citrus leaf blotch virus, a new virus from Nagami kumquat. Archives of Virology 146: 357–368.
Gress, J. C., S. Smith, and I. E. Tzanetakis. 2017. First report of Citrus leaf blotch virus in peony in the U.S.A. Plant Disease 101: 637. https://doi.org/10.1094/PDIS-08-16-1218-PDN
Guardo, M., G Sorrentino, T. Marletta and A. Carusa. 2007. First report of Citrus leaf blotch on kumquat in Italy. Plant Disease 91: 104.
Guardo, M., O. Potere, M. A. Castellano, V. Savino and A. Caruso. 2009. A new herbaceous host for Citrus leaf blotch virus. Journal of Plant Pathology 91: 485-488.
Guardo, M., G. Sorrentino and A. Caruso. 2015. Characterization and incidence of Citrus leaf blotch virus in Southern Italy. 12th International Citrus Congress – International Society of Citriculture. Acta Horticulturae 1065: 825-83.
Hajeri, S., C. Ramadugu, M. Keremane, G. Vidalakis and R. Lee. 2010. Nucleotide sequence and genome organization of Dweet mottle virus and its relationship to members of the family Betaflexiviridae. Arch Virol 15: 1523-1527. DOI 10.1007/s00705-010-0758-1
Harper, S. J., K. M. Chooi and M. N. Pearson. 2008. First report of Citrus leaf blotch virus in New Zealand. Plant Disease 92: 1470. https://doi.org/10.1094/PDIS-92-10-1470C
Hernàndez-Rodríguez, L., J. M. Pérez-Castro, G. García-García, P. Luis Ramos-González, V. Zamora-Rodríguez, Xenia Ferriol-Marchena, Inés Peña-Bárzaga and L. Batista-Le Riverend. 2016. Citrus leaf blotch in Cuba: first report and partial molecular characterization. Tropical Plant Pathology 41: 147. https://doi.org/10.1007/s40858-016-0078-4
Krueger, R. R., J. A. Bash and R. F. Lee. 2005. Phytosanitary status of California citrus. International Organization of Citrus Virologists Conference Proceedings (1957-20), 16 (16): 468-472. https://escholarship.org/uc/item/3667q9qn
Krueger, R. R., J. A. Bash and R. F. Lee. 2012. Dweet mottle virus and Citrus leaf blotch virus. http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=7112
Navarro, L., J. A. Pina, J. F. Ballester-Olmos, P. Moreno and M. Cambra. 1984. A new graft transmissible disease found in Nagami kumquat. In: Timmer L. W., and J. A. Dodds (eds) Proceedings of the 9th Conference of the International Organization of Citrus Virologists, IOCV, Riverside, pp 234–240.
Roistacher, C. N., and R. L. Blue. 1968. A psorosis-like virus causing symptoms only on ‘Dweet’ tangor. International Organization of Citrus Virologists Conference Proceedings (1957-2010), 4(4): 13-18.
Roistacher, C. N., E. M. Nauer and R. C. Wagner. 1980. Transmissibility of cachexia, Dweet mottle, psorosis and infectious variegation viruses on knife blades and its prevention. Proceedings of the 8th Conference of the International Organization of Citrus Virologists, IOCV, Riverside 1980: 225-229.
USDA PCIT. 2018. USDA Phytosanitary Certificate Issuance & Tracking System. Retrieved March 15, 2018. 3:25:54 pm CDT. https://pcit.aphis.usda.gov/PExD/faces/ReportHarmOrgs.jsp.
Vives, M. C., L. Galipienso, L. Navarro, P. Moreno and J. Guerri. 2001. The nucleotide sequence and genomic organization of Citrus leaf blotch virus: Candidate type species for a new virus genus. Virology 287: 225-233.
Vives, M. C., L. Galipienso, L. Navarro, P. Moreno and J. Guerri. 2002. Citrus leaf blotch virus: a new citrus virus associated with bud union crease on trifoliate rootstocks. International Organization of Citrus Virologists Conference Proceedings (1957-2010), 15 (15): 205-212.
Vives, M. C., L. Rubio, L. Galipienso, L. Navarro, P. Moreno and J. Guerri. 2002. Low genetic variation between isolates of Citrus leaf blotch virus from different host species and different geographical origins. Journal of General Virology 83: 2587–2591.
Vives M. C., J. A. Pina, J. Juarez, L. Navarro, P. Moreno and J. Guerri. 2005. Dweet mottle disease is probably caused by Citrus leaf blotch virus. 16th Conference of the International Organization of Citrus Virologists Conference Proceedings (1957-2010), 15 (16): 251-256.
Vives, M. C., S. Martin, S. Ambros, A. Renovell, L. Navarro, J. A. Pina, P. Moreno, J. and J. Guerri. 2008a. Development of a full-genome cDNA clone of Citrus leaf blotch virus and infection of citrus plants. Molecular Plant Pathology 9:787–797.
Vives, M. C., P. Moreno, L. Navarro and J. Guerri. 2008b. Citrus leaf blotch virus. In: Rao, G. P., A. Myrta and K. Ling (eds). Characterization, Diagnosis and Management of Plant Viruses, vol. 2. Pp. 55-67. Studium Press, Houston, TX, USA.
Wang, J., D. Zhu, Y. Tan, X. Zong, H. Wei and Q. Liu. 2016. First report of Citrus leaf blotch virus in sweet cherry. Plant Disease 100:1027.
Zhu, Chen-xi, Wang, Guo-ping, Zheng, Ya-zhou, Yang, Zuo-kun, Wang, Li-ping, Xu, Wen-xing and N. Hong. 2016. RT-PCR detection and sequence analysis of coat protein gene of Citrus leaf blotch virus infecting kiwifruit trees. Acta Phytopathologica Sinica, 46 (1): 11.
John J. Chitambar, Primary Plant Pathologist/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.
You must be registered and logged in to post a comment. If you have registered and have not received the registration confirmation, please contact us at plant.health[@]cdfa.ca.gov.
♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.
Example Comment:
Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]
♦ Posted comments will not be able to be viewed immediately.
♦ Comments may not be posted if they:
Contain inappropriate language which is not germane to the pest rating proposal;
Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;
Violates agency regulations prohibiting sexual harassment or other forms of discrimination;
Violates agency regulations prohibiting workplace violence, including threats.
♦ Comments may be edited prior to posting to ensure they are entirely germane.
♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.
Posted by ls
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