Cucurbit yellow stunting disorder crinivirus

Abstract

EPPO BulletinVolume 35, Issue 3 p. 442-444 Free Access Cucurbit yellow stunting disorder crinivirus First published: 19 December 2005 https://doi.org/10.1111/j.1365-2338.2005.00847.xCitations: 1 European and Mediterranean Plant Protection Organization Organisation Européenne et Méditerranéenne pour la Protection des Plantes AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Identity Name: Cucurbit yellow stunting disorder virus Taxonomic position: Viruses: Closteroviridae: Crinivirus Synonyms: Cucurbit yellow stunting disorder closterovirus Common name: CYSDV (acronym) Notes on taxonomy and nomenclature: CYSDV can be divided into two divergent groups of isolates. One group is composed of isolates from Spain, Lebanon, Jordan, Turkey and North America and the other of isolates from Saudi Arabia. Nucleotide identity between isolates of the same group is greater than 99%, whereas identity between groups is about 90% (Rubio et al., 1999) EPPO code: CYSDV0 Phytosanitary categorization: EPPO A2 action list no. 324; since CYSDV is transmitted by Bemisia tabaci, it was before its establishment in Portugal and Spain regulated by the EU as a non-European virus transmitted by that species (Annex I/A1) Hosts The natural hosts of CYSDV are restricted to Cucurbitaceae: watermelon, melon, cucumber, courgette. In addition, the following experimental host plants have been identified: Cucurbita maxima and Lactuca sativa. For further details, see Abou-Jawdah et al. (2000); Berdiales et al. (1999); Célix et al. (1996); Desbiez et al. (2000); Kao et al. (2000); Louro et al. (2000); Wisler et al. (1998). Geographical distribution EPPO region: Israel (Wisler et al., 1998), Jordan (Wisler et al., 1998; Rubio et al., 1999), Morocco (Desbiez et al., 2000), Portugal (Louro et al., 2000), Spain (Célix et al., 1996; including Canary Islands), Turkey (Wisler et al., 1998; Rubio et al., 1999). In the south of France, two isolated outbreaks were found in winter 2001/2002 but were successfully eradicated (Decoin, 2003) Asia: Lebanon (Abou-Jawdah et al., 2000), Saudi Arabia (Wisler et al., 1998; Rubio et al., 1999), Syria (Hourani & Abou-Jawdah, 2003), United Arab Emirates (Hassan & Duffus, 1991) Africa: Egypt (Wisler et al., 1998), Morocco North America: Mexico, USA (Texas –Kao et al., 2000) EU: present Biology The life cycle of CYSDV is strongly dependent on its vector, the whitefly Bemisia tabaci, also a regulated pest (EPPO/CABI, 1997). In Portugal, the first symptoms of CYSDV in a field plot of cucumber were associated with heavy infestations of B. tabaci (Louro et al., 2000). High populations were also associated with symptoms on melon in the USA (Kao et al., 2000). The spread of the virus may be related to the increase in distribution of the polyphagous B biotype of B. tabaci (also known as B. argentifolii; Bellows et al., 1994). This moves readily from one host species to the next and is estimated to have a host range of around 600 species. Transmission of CYSDV by biotype B is greater than by biotype A (Wisler et al., 1998). However, biotype Q transmits as efficiently as biotype B (Berdiales et al., 1999). The international trade in poinsettia is thought to have been a major means of dissemination of the B biotype within the EPPO region (EPPO/CABI, 1997). Within the EPPO region, biotype B is present and widespread in the field in many countries bordering the Mediterranean basin as well as in Slovakia and Ukraine. In northern European countries, it is of limited distribution and confined almost totally to glasshouse crops. Biotype Q is specific to Portugal and Spain (EPPO/CABI, 1997). B. tabaci infests polyethylene-covered glasshouses where melons and cucumbers are grown along the south-east coast of Spain. It is displacing Trialeurodes vaporariorum as the dominant whitefly in this area and is associated with the change in the agent causing yellowing diseases of cucurbits from Beet pseudo-yellows closterovirus (BPYV) to CYSDV (Célix et al., 1996). Acquisition periods of 18 h or more and inoculation periods of 24 h or more are necessary for transmission rates of CYSDV of over 80% in tests using melon. However transmission was noted after an acquisition and transmission periods of 2 h (Célix et al., 1996). Research has also shown that CYSDV persists for at least 9 days in the vector with a 72.2-h half-life. This is the longest retention time of all whitefly-transmitted Closteroviridae (Wisler et al., 1998). CYSDV is not known to be seed-borne. Detection and identification Symptoms Cucumbers and melons affected by CYSDV show severe yellowing symptoms that start as an interveinal mottle on the older leaves and intensify as leaves age (Abou-Jawdah et al., 2000). Chlorotic mottling, yellowing and stunting occur on cucumber (Louro et al., 2000) and yellowing and severe stunting on melon (Kao et al., 2000). No description of symptoms on courgette has been provided by the authors reporting the natural infection (Berdiales et al., 1999). Symptoms on cucurbit crops are said to be indistinguishable from those caused by BPYV (Wisler et al., 1998). In experimental transmission experiments, chlorotic spots along the leaf veins of the melon cv. ‘Piel de Sapo’ were noticed after 14–20 days. Sometimes, initial symptoms also consisted of prominent yellowing sectors of a leaf. Symptoms evolved later to complete yellowing of the leaf lamina, except the veins, and rolling and brittleness of the leaves (Célix et al., 1996). Morphology Flexuous, filamentous virus particles typical of the Closteroviridae have been found in infected plants. The length distribution of CYSDV particles has shown two peaks at 825–850 nm and 875–900 nm (Célix et al., 1996). Using an improved method for particle measurement, Liu et al. (2000) have recorded lengths of 800–850 nm for CYSDV. Analysis of double-stranded (ds) RNA extracts has revealed two major dsRNA species of approximately 8 and 9 kbp. On this basis, CYSDV was classed with the Closterovirus spp. with bipartite genomes exemplified by Lettuce infectious yellows closterovirus (Célix et al., 1996), as then named. These have now been transferred to a new genus Crinivirus. Detection and inspection methods CYSDV in infected tissue can be identified by RT-PCR detection assay (Berdiales et al., 1999; Célix et al., 1996) and by dot–blot hybridization analysis using CYSDV-specific probes (Rubio et al., 1999; Tian et al., 1996). Antiserum has been produced and used in both immunoblot and indirect ELISA assays (Livieratos et al., 1999). Pathways for movement Within cucurbit crops, natural spread of CYSDV is ensured by its vector, B. tabaci. Adults of B. tabaci do not fly very efficiently but, once airborne, can be transported long distances in air currents. Internationally, infected young plants of cucurbits intended for planting are a likely pathway to introduce or spread the disease. Also, all stages of the whitefly vector can be carried on plants for planting. There is not, however, known to be a significant movement of cucurbit plants for planting from areas where the disease occurs. Pest significance Economic impact Since the late 1970s, cucumbers and melons grown in 16 000 ha of polyethylene-covered glasshouses in south-east Spain have been seriously affected by yellowing diseases transmitted by whiteflies. The first epidemics were caused by BPYV transmitted by T. vaporariorum. Since the early 1990s, in addition to BPYV, CYSDV has been associated with these diseases. Surveys undertaken in 1994/1997 have shown that CYSDV has displaced BPYV as the major virus pathogen. No figures are available on losses caused by CYSDV. In Lebanon, the incidence of CYSDV has been high in summer and early autumn cucurbit crops grown in polyethylene tunnels along the coast. Yield reductions of 40–60% have been reported by farmers. Incidence was much higher in unscreened tunnels than in screened tunnels (Abou-Jawdah et al., 2000). Control The control of CYSDV centres on the control of its vector B. tabaci, and elimination of sources of infection. In particular, cucurbit seedlings for planting should come from disease-free stocks. Chemical control of populations of B. tabaci to levels that result in a significant drop in disease incidence has proved difficult. In general, chemical control of the vectors of Closteroviridae has not been effective in preventing the spread of the diseases they cause (Berdiales et al., 1999). Some of the difficulties are the wide host range of the vector, the presence of the whitefly on the undersides of leaves, the extreme motility of adults and the ability of B. tabaci to develop resistance to most classes of existing insecticides. Many conventional insecticides such as organophosphorus compounds, carbamates and pyrethroids have effectively reduced whitefly populations, but provided only partial virus control even when sprayed as frequently as 2–3 times a week (Nakhla & Maxwell, 1998). Imidacloprid, a systemic insecticide that can be applied to soil and foliage, is used to control whiteflies, but resistance is now reported (Elbert & Nauen, 2000). Insects resistant to aldicarb and buprofezin were also detected (Anonymous, 1996). The parasite Encarsia formosa and the fungus Verticillium lecanii can be used as biological agents against B. tabaci, but are unlikely to affect virus transmission. Cultural control: roguing infected cucurbit plants and removing overwintering crops early in the spring prior to the emergence of adult whiteflies may prove useful. To be effective, this sort of control measure should be applied over a whole area and preferably where there is no continuous production in glasshouses, which are often the sites of whitefly activity and active virus spread throughout the year. Weeds in and surrounding glasshouses should also be destroyed as they could act as hosts for B. tabaci. In Israel, covering the soil with a mulch of sawdust, fresh wheat straw or yellow polyethylene sheets has markedly reduced populations of B. tabaci. Whiteflies are attracted to the yellow colour and are killed by the heat. The fading of the mulch colour and changes in the ratio of canopy to mulch area is believed to cause a reduction in control. Interplanting with a species that is a good host for the vector, but not the virus may reduce virus incidence. In Lebanon, insect-proof nets and sticky yellow traps are used for control (Abou-Jawdah et al., 2000). Growing plants under physical barriers, such as low mesh tunnels and shade-cloth, may also have a positive effect. No resistant cultivars of susceptible hosts are currently available commercially. Phytosanitary risk Cucurbits are important crops in the EPPO region, both in the field and under glass, and CYSDV causes a serious disease notably on cucumbers and melons in Spain, Portugal, Turkey and the Middle East. Within Europe, cucumber and gherkin production is significant. In 2000, 1.66 million t were harvested in the EU. the Netherlands and Spain were the biggest producers, harvesting 465 000 and 420 000 t, respectively, according to FAO. Economic losses from CYSDV that could be expected in glasshouse-grown cucurbits, especially cucumber, in northern Europe are difficult to predict, but are likely to be substantial. Spread of the pest is likely to be much facilitated by the presence of its vector B. tabaci in glasshouses in many countries of the EPPO region. Control of CYSDV is difficult due to the ability of the vector B. tabaci rapidly to become resistant to insecticides. A breakdown of efficacy of insecticides could result in serious problems. There is a strong probability that CYSDV will become a serious problem in other Mediterranean countries and in northern Europe, if introduced. Phytosanitary measures CYSDV was added in 2004 to the EPPO A2 action list, and endangered EPPO member countries are thus recommended to regulate it as a quarantine pest. For the moment, there are no specific measures against CYSDV in Europe, and in particular there are no restrictions on the movement of cucurbit seedlings from areas where the disease occurs. There is a potential danger that infected seedlings could move from countries where CYSDV occurs to other parts of the region, thus spreading the virus. Possible measures would be the same as those proposed for CVYV (OEPP/EPPO, 2005). Acknowledgements This data sheet was originally drafted by D. Jones, Central Science Laboratory, York (GB). References Abou-Jawdah Y, Sobh H, Fayad A, Lecoq H, Delécolle B & Trad-Ferré J (2000) Cucurbit yellow stunting disorder virus– a new threat to cucurbits in Lebanon. Journal of Plant Pathology 82, 55– 60. Google Scholar Anonymous (1996) Meeting the Threat of the Tobacco Whitefly (Bemisia Tabaci) to UK Horticulture. Final Project Report 1996 . IACR, Rothamsted (GB). Google Scholar Bellows TS, Perring TM, Gill RJ & Headrick DH (1994) Description of a species of Bemisia. Annals of the Entomological Society of America 87, 195– 206. CrossrefWeb of Science®Google Scholar Berdiales B, Bernal JJ, Sáez E, Woudt B, Beitia F & Rodríguez-Cerezo E (1999) Occurrence of cucurbit yellow stunting disorder virus (CYSDV) and beet pseudo-yellows virus in cucurbit crops in Spain and transmission of CYSDV by two biotypes of Bemisia tabaci. European Journal of Plant Pathology 105, 211– 215. CrossrefWeb of Science®Google Scholar Célix A, López-Sesé A, Almarza N, Gómez-Guillamón ML & Rodríguez-Cerezo E (1996) Characterization of cucurbit yellow stunting disorder virus, a Bemisia tabaci-transmitted closterovirus. Phytopathology 86, 1370– 1376. CASWeb of Science®Google Scholar Decoin M (2003) Tomates et concombres, gare aux nouveaux virus. Phytoma – la Défense des Végétaux n° 558, 27– 29. Google Scholar Desbiez C, Lecoq H, Aboulama S & Peterschmitt M (2000) First report of Cucurbit yellow stunting disorder virus in Morocco. Plant Disease 84, 596. CrossrefCASPubMedGoogle Scholar Elbert A & Nauen R (2000) Resistance of Bemisia tabaci to insecticides in southern Spain with special reference to neonicotinoids. Pest Management Science 56, 60– 64. Wiley Online LibraryCASWeb of Science®Google Scholar EPPO/ CABI (1997) Bemisia tabaci . In: Quarantine Pests for Europe, 2nd edn, pp. 121– 127. CAB International, Wallingford (GB). Google Scholar Hassan AA & Duffus JE (1991) A review of a yellowing stunting disorder of cucurbits in the United Arab Emirates. Emirates Journal of Agricultural Science 2, 1– 16. CrossrefGoogle Scholar Hourani H & Abou-Jawdah Y (2003) Immunodiagnosis of Cucurbit yellow stunting disorder virus using polyclonal antibodies developed against recombinant coat protein. Journal of Plant Pathology 85, 197– 204. CASWeb of Science®Google Scholar Kao J, Jia L, Tian T, Rubio L & Falk BW (2000) First report of Cucurbit yellow stunting disorder virus (genus Crinivirus) in North America. Plant Disease 84, 101. CrossrefCASPubMedGoogle Scholar Liu HY, Wisler GC & Duffus JE (2000) Particle lengths of whitefly-transmitted criniviruses. Plant Disease 84, 803– 805. CrossrefWeb of Science®Google Scholar Livieratos IC, Avgelis AD & Coutts RHA (1999) Molecular characterization of the cucurbit yellow stunting disorder virus coat protein. Phytopathology 89, 1050– 1055. CrossrefCASPubMedWeb of Science®Google Scholar Louro D, Vicente M, Vaira AM, Accotto GP & Nolasco G (2000) Cucurbit yellow stunting disorder virus (Genus Crinivirus) associated with the yellowing disease of cucurbit crops in Portugal. Plant Disease 84, 1156. CrossrefCASPubMedGoogle Scholar Nakhla MK & Maxwell DP (1998) Epidemiology and management of tomato yellow leaf curl virus. In: Plant Virus Disease Control (Eds A Hadidi, RK Khetarpal & H Kodanezawa), pp. 565– 583. APS Press, St Paul (US). Google Scholar OEPP/EPPO (2005) Data sheets on quarantine pests. Cucumber vein yellowing ipomovirus. Bulletin OEPP/EPPO Bulletin 35, 419– 421. Wiley Online LibraryGoogle Scholar Rubio L, Soong J, Kao J & Falk BW (1999) Geographic distribution and molecular variation of isolates of three whitefly-borne closteroviruses of cucurbits: lettuce infectious yellows virus, cucurbit yellow stunting disorder virus, and beet pseudo-yellows virus. Phytopathology 89, 707– 711. CrossrefCASPubMedWeb of Science®Google Scholar Tian T, Klaassen VA, Soong J, Wisler G, Duffus JE & Falk BW (1996) Generation of cDNAs specific to lettuce infectious yellows closterovirus and other whitefly-transmitted viruses by RT-PCR and degenerate oligonucleotide primers corresponding to the closterovirus gene encoding the heat shock protein 70 homolog. Phytopathology 86, 1167– 1173. CrossrefCASWeb of Science®Google Scholar Wisler GC, Duffus JE, Liu HY & Li RH (1998) Ecology and epidemiology of whitefly-transmitted closteroviruses. Plant Disease 82, 270– 280. CrossrefCASPubMedWeb of Science®Google Scholar Citing Literature Volume35, Issue3December 2005Pages 442-444 ReferencesRelatedInformation