Martin Chilvers, Ph.D.

Martin Chilvers

Contact Me

Associate Professor - Field Crop Pathology
Montcalm Research Center

Phone:
517-353-9967

Email:

Degrees:
B.Ag.Sci (Hons), University of Tasmania
Ph.D., University of Tasmania
Postdoc, Washington State University

Overview of current program:

Soybean sudden death syndrome (SDS) is caused by the fungus Fusarium virguliforme, and has potential to significantly reduce yields. The 2010 growing season saw unprecedented levels of SDS across Michigan and north central states. Observations indicate that SDS appears to be established in the lower half of Michigan and is moving north. SDS is a difficult disease to detect and monitor as it is soil borne and does not always produce distinctive foliar symptoms. In addition, foliar SDS symptoms can often be confused with other soybean diseases.  We are mapping the distribution of F. virguliforme in Michigan to county level and examining it’s interaction with the soybean cyst nematode (SCN) using a combination of molecular and culturing techniques. We are also developing and refining greenhouse screening techniques for SDS resistance in collaboration with MSU’s soybean breeder Dr. Dechun Wang.

The soil environment is complex and contains many thousands of microbe species, but only a small portion of these actually cause disease. Current trends of early planting and minimum-tillage practices enhance conditions for seedling and root rot diseases. We have begun addressing the complexity of this system using traditional and cutting edge techniques. In the NIFA-CAP project “Integrated management of oomycete diseases of soybean and other crop plants”, we identified and characterized the predominant oomycete (Pythium, Phytophthora, and Phytopythium) species significantly improving our understanding of the ecology and etiology of soybean oomycete seedling disease across 12 U.S. states and Ontario Canada. These data and resources have aided in disease diagnostics, development and testing of seed treatments and screening for disease resistance.

Sclerotinia white mold, caused by Sclerotinia sclerotiorum, is a devastating disease of many crop plants and can cause significant economic losses in pea under the appropriate environmental conditions. We are interested in dissecting the pea-Sclerotinia sclerotiorum interaction through a combination of gene expression profiling studies (RNAseq) and use of genome wide association analysis (GWAS). Despite being Mendel’s model system, few genomic resources exist for pea. The expression profiling studies will provide valuable information on the genetics of the interaction between host and pathogen. Identification of genes and pathways involved in partial resistance will lead to a better understanding of the interaction and development of markers for breeding resistance to S. sclerotiorum. We envisage that these studies will lead to further insights and solutions for development of resistant material not only in pea but in other crops affected by Sclerotinia spp. We are also collaborating with colleagues at the University of Wisconsin-Madison, Iowa State University and others in the development of apothecia risk assessment models, and optimized fungicide management recommendations in soybeans.

We have a strong interest in the development and more importantly application of molecular detection assays including high-through put systems and have worked on the development and application of several real-time PCR and standard PCR multiplex assays. My program is particularly interested in utilizing genomic resources and nuclide acid detection technologies to improve our understanding of fungal biology, disease etiology and epidemiology.

Extension and outreach activities:

Our Extension interests include the development of effective programming that addresses grower concerns and minimizes losses to field crop diseases, while improving sustainability of cropping systems. Extension activities include field days, annual meetings, publication of Crop Protection Network (CPN) articles (www.cropprotectionnetwork.org) and MSUE alerts (www.msue.anr.msu.edu/topic/info/field_crops), as well as participation in disease observation data for Michigan through ipmPIPE (www.ipmpipe.org) and national disease loss estimates.

 

Publications: 

  1. Noel, Z.A., Wang, J. Chilvers, M.I. 2017, accepted pending minor corrections. Guidelines fo r accurate EC50 estimation for fungal and oomycete plant pathogens. Plant Disease Available on first look
  2. Willbur, J.F., Fall, M.L., Bloomingdale, C.A., Byrne, A.M., Chapman, S.A., Isard, S.A., Magarey, R.D., McCaghey, M., Mueller, B.D., Russo, J.M., Schlegel, J., Chilvers, M.I., Mueller, D.S., and Smith, D.L. Available online. Development of a predictive model for Sclerotinia sclerotiorum apothecial development in irrigated and non-irrigated soybean fields. Plant Dis. https://doi.org/10.1094/PDIS-04-17-0504-RE
  3. Romero, L.M., Aime, M.C., Chilvers, M.I., Wise, K.A. Accepted July 17, 2017. Genetic diversity of Stenocarpella maydis in the major corn production areas of the United States. Plant Disease https://doi.org/10.1094/PDIS-02-17-0292-RE
  4. Zeng, Q., Wang, J., Bertels, F., Giordano, P.R., Chilvers, M.I., Huntley, R., Vargas, J.M., Sundin, G.W., Jacobs, J.L., Yang, C.H. 2017. Recombination of virulence genes in divergent Acidovorax avenae strains that infect a common host. Molecular Plant-Microbe Interactions 30:813-828
  5. Kandel, Y. R., Wise, K. A., Bradley, C. A., Chilvers, M. I., Byrne, A. M., Tenuta, A. U., Faghihi, J., Wiggs, S. N., Tylka, G. L. and Mueller, D. S. Accepted Jul 5, 2017. Effect of SCN resistance source and seed treatment on population densities of Heterodera glycines, sudden death syndrome, and yield of soybean. Plant Dis. https://doi.org/10.1094/PDIS-12-16-1832-RE
  6. Rossman, D.R., Rojas, A., Jacobs, J.L., Mukankusi, C., Kelly, J.D., Chilvers, M.I. 2017. Pathogenicity and virulence of soilborne oomycetes on Phaseolus vulgaris. Plant Disease 101:1851-1859 https://doi.org/10.1094/PDIS-02-17-0178-RE
  7. Rojas, J.A., Miles, T., Coffey, M., Martin, F.N., Chilvers, M.I. Development and application of qPCR and RPA genus and species-specific detection of Phytophthora sojae and Phytophthora sansomeana root rot pathogens. Plant Disease 101:1171-1181
  8. Allen, T.W., Bradley, C.A., Sisson, A.J., Byamukama, E., Chilvers, M.I., Coker, C.M., Collins, A.A., Damicone, J.P., Dorrance, A.E., Dufault, N.S., Esker, P.D., Faske, T.R., Giesler, L.J., Grybauskas, A.P., Hershman, D.E., Hollier, C.A., Isakeit, T., Jardine, D.J., Kemerait, R.C., Kleczewski, N.M., Koenning, S.R., Kurle, J.E., Malvick, D.K., Markell, S.G., Marois, J.J., Mehl, H.L., Mueller, D.S., Mueller, J.D., Mulrooney, R.P., Nelson, B.D., Newman, M.A., Osborne, L., Overstreet, C., Padgett, G.B., Phipps, P.M., Price, P.P., Sikora, E.J., Smith, D.L., Spurlock, T.N., Tande, C.A., Tenuta, A.U., Wise, K.A., Wrather, J.A., and Young-Kelly, H. 2017. Soybean yield loss estimates due to diseases in the United States and Ontario, Canada from 2010 to 2014. Plant Health Progress 18:19-27 doi:10.1094/PHP-RS-16-0066
  9. Gaspar, A.P., Chilvers, M.I., Wise, K.A., Tenuta, A.U., Mueller, D.S., Conley, S.P. 2017. Response of broad spectrum and target specific seed treatments and seeding rate on soybean seed yield, profitability, and economic risk across diverse environments. Crop Science 56:1-12 Doi:10.2135/cropsci2016.11.0967
  10. Wang, J., Bradley, C.A., Stenzel, O., Pedersen, D.K., Reuter-Carlson, U., Chilvers, M.I. 2017. Baseline sensitivity of Fusarium virguliforme to fluopyram fungicide. Plant Disease 101:576-582
  11. Rojas, J.A, Jacobs J., Napieralski, S., Karaj, B., Bradley, C.A., Chase, T., Esker, P., Giesler, L., Jardine, D., Malvick, D. Markell, S., Nelson, B., Robertson, A., Rupe, J., Smith, D., Sweets, L., Tenuta, A., Wise, K., Chilvers, M.I. Oomycete species associated with soybean seedlings in North America – Part I: Identification and pathogenicity characterization. Phytopathology 107:280-292
  12. Rojas, J.A, Jacobs J., Napieralski, S., Karaj, B., Bradley, C.A., Chase, T., Esker, P., Giesler, L., Jardine, D., Malvick, D. Markell, S., Nelson, B., Robertson, A., Rupe, J., Smith, D., Sweets, L., Tenuta, A., Wise, K., Chilvers, M.I. Oomycete species associated with soybean seedlings in North America – Part II: Diversity and ecology in relation to environmental and edaphic factors. Phytopathology 107:293-304
  13. Kuhlgert, S., Austic, G., Zegarac, R., Osei-Bonsu, I., Hoh, D., Chilvers, M.I., Roth, M.G., Bi, K., TerAvest, D., Weebadde, P., Kramer, D.M. 2016. MultispeQ Beta – A tool for large-scale plant phenotyping connected to the open PhotosynQ network. Royal Society Open Science. 3:160592
  14. Batzer, J.C., Kandel, Y.R., Bradely, C.A., Chilvers, M.I., Tenuta, A.U., Wise, K.A., Hernández, E., and Mueller, D.S. 2016. Effect of seed treatment on early season brown spot caused by Septoria glycines of soybean. Online Plant Health Progress 17:223-228 doi:10.1094/PHP-RS-16-0035
  15. Mueller, D., Wise, K.A., Sisson, A.J., Allen, T.A., Bergstrom, G.C., Bosley, D.B., Bradley, C.A., Broders, K.D., Byamukama, E., Chilvers, M.I., Collins, A., Faske, T.R., Friskop, A.J., Heiniger, R.W., Hollier, C.A., Hooker, D.C., Isakeit, T., Jackson-Ziems, T.A., Jardine, D.J., Kelly, H.M., Kinzer, K., Koenning, S.R., Malvick, D.K., McMullen, M., Meyer, R.F., Paul, P.A., Robertson, A.E., Roth, G.W., Smith, D.L., Tande, C.A., Tenuta, A.U., Vincelli, P., and Warner, F. 2016. Corn Yield Loss Estimates Due to Diseases in the United States and Ontario, Canada from 2012 to 2015. Plant Heath Progress. 17:211-222. doi:10.1094 / PHP-RS-16-0030
  16. Kandel, Y.R., Wise, K.A., Bradley, C.A., Tenuta, A.U., Chilvers, M.I., Mueller, D.S. 2016. Fungicide and cultivar effects on sudden death syndrome and yield of soybean. Plant Disease 100:1339-1350
  17. Wang J., Chilvers, M.I. 2016. Development and characterization of microsatellite markers for Fusarium virguliforme and their transferability to clade 2 of the Fusarium solani species complex. Fungal Ecology 20:7-14
  18. Kandel, Y.R., Haudenshield, J., Srour, A.Y., Islam, K.T., Fakhoury, A.M., Santos, P., Wang, J., Chilvers, M.I., Hartman, G., Malvick, D., Floyd, C.M., Mueller, D., Leandro, L. 2015. Multi-laboratory comparison of quantitative PCR assays for detection and quantification of Fusarium virguliforme from soybean roots and soil. Phytopathology 105:1601-1611 (Editors pick)
  19. Olson, T.R., Gebreil, A., Micijevic, A., Bradley, C., Wise, K.A., Mueller, D.S., Chilvers, M.I., Mathew, F.M. 2015. Association of Diaporthe longicolla with black zone lines on mature soybean plants. Plant Health Progress doi:10.1094/PHP-RS-15-0020
  20. Wang J., Jacobs, J.L., Byrne, J.M. Chilvers, M.I. Improved diagnoses and quantification of Fusarium virguliforme, causal agent of soybean sudden death syndrome. Phytopathology 105:378-387
  21. Kandel, Y., Bradley, C., Wise, K., Chilvers, M., Tenuta, A., Davis. V., Esker, P., Smith, D., Licht, M., Mueller, D. 2015. Effect of glyphosate application on sudden death syndrome of glyphosate-resistant soybean under field conditions. Plant Disease 99:347-354
  22. Wen, Z., Tan, R., Yuan, J., Bales, C., Du, W., Zhang, S., Chilvers, M.I., Schmidt, C., Song, Q., Cregan, P., Kull, L., Wang, D. 2014. Genome-wide association mapping of quantitative resistance to sudden death syndrome in soybean. BMC Genomics 15:809
  23. Chilvers, M.I., Jones, S., Meleca, J., Peever, T., Pethybridge, S., Hay, F. 2014. Characterization of mating type genes supports the hypothesis that Stagonosporopsis chrysanthemi is homothallic and provides evidence that Stagonosporopsis tanaceti is heterothallic. Current Genetics. 60:295-302.
  24. Sikora, E.J., Allen, T.W., Wise, K.A., Chilvers M.I. et al. 2014. A coordinated effort to manage soybean rust in North America: a success story in soybean disease monitoring. Plant Disease (Featured Article). 98:864-875
  25. Stewart, J.E., Andrew, M., Bao, X., Chilvers, M.I., Carris, L.M., Peever, T.L. 2013. Development and utility of sequence characterized amplified genomic regions (SCAR) for lower-level fungal systematics: Proof of principle using Alternaria, Ascochyta and Mycologia 105:1077-86.
  26. Zhuang, X, McPhee, K.E., Coram, T.E., Peever, T.L., Chilvers, M.I. 2013. Development and characterization of 37 novel EST-SSR markers in Pisum sativum (Fabaceae). Applications in Plant Sciences 1(1):1200249
  27. Zhuang, X, McPhee, K.E., Coram, T.E., Peever, T.L., Chilvers, M.I. Rapid transcriptome characterization and parsing of sequences in a non-model host-pathogen interaction; pea-Sclerotinia sclerotiorum. BMC Genomics 13:668
  28. Akamatsu, H.O., Chilvers, M.I., Kaiser, W.J., Peever, T.L. 2012. Karyotype polymorphism and chromosomal rearrangement in populations of the phytopathogenic fungus, Ascochyta rabiei. Fungal Biology. 116:1119-1133
  29. Peltier, A.J., Bradley, C.A., Chilvers, M.I., Malvick, D.K., Mueller, D.S., Wise, K.A., Esker, P.D. 2012. Biology, yield loss, and control of Sclerotinia stem rot of soybean. Journal of Integrated Pest Management. 3(2):B1-B7
  30. Ozkilinc, H., Akamatsu, H. Abang, M., Thomas, K., Chilvers, M.I., Peever, T.L. 2011. Development, characterization and linkage analysis of microsatellite loci for the Ascochyta blight pathogen of faba bean, Didymella fabae. Journal of Microbiological Methods 87:128-130
  31. Akamatsu, H.O., Chilvers, M.I., Stewart, J.E. and Peever, T.L. 2010. Identification and function of a polyketide synthase gene responsible for 1,8-dihydroxynaphthalene-melanin pigment biosynthesis in Ascochyta rabiei. Current Genetics 56:349-360
  32. Frenkel, O., Peever T.L., Chilvers, M.I., Özkilinc, H., Can, C., Abbo, S., Shtienberg, D. and Sherman A. 2010. Ecological divergence of the fungal pathogen Didymella rabiei on sympatric wild and domesticated chickpea. Applied and Environmental Microbiology 76:30-39
  33. Chilvers, M.I., Rogers, J.D., Dugan, F.M., Stewart, J.E., Chen, W. and Peever, T.L. 2009. Didymella pisi nov., the teleomorph of Ascochyta pisi. Mycological Research 113:391-400
  34. Dugan, F.M., Akamatsu, H., Lupien, S.L., Chen, W., Chilvers, M.I., and Peever, T.L. 2009. Ascochyta blight of chickpea reduced 38% by application of Aureobasidium pullulans (anamorphic Dothioraceae, Dothideales) to post-harvest debris. Biocontrol Science and Technology 19:537-545
  35. Chilvers, M.I., Peever, T.L., Kaiser, W.J., Akamatsu, H., Chen, W., and Muehlbauer, F.J. 2007. Didymella rabiei ascospore release from chickpea debris in relation to weather variables in the Pacific Northwest of the United States. Canadian Journal of Plant Pathology 29:365-371
  36. Chilvers, M.I., du Toit L.J., Akamatsu, H., and Peever, T.L. 2007. A real-time, quantitative PCR seed assay for Botrytis that cause neck rot of onion. Plant Disease 91:599-608
  37. Akamatsu, H.O., Grünwald, N.J., Chilvers, M.I., Porter, L.D., and Peever, T.L. 2007. Development of codominant simple sequence repeat, single nucleotide polymorphism and sequence characterized amplified region markers for the pea root rot pathogen, Aphanomyces euteiches. Journal of Microbiological Methods 71:82-86
  38. Chilvers, M.I., and du Toit L.J. 2006. Detection and identification of Botrytis species associated with neck rot, scape blight, and umbel blight of onion. Online. Plant Health Progress doi:10.1094/PHP-2006-1127-01-DG
  39. Chérif, M., Chilvers, M.I., Akamatsu, H., Kaiser, W.J., and Peever, T.L. 2006. Cloning of the mating type locus from Ascochyta lentis (teleomorph: Didymella lentis) and development of a multiplex PCR mating assay for Ascochyta Current Genetics 50:203-215
  40. Hernandez-Bello, M.A., Chilvers, M.I., Akamatsu, H., and Peever, T.L. Host specificity of Ascochyta species infecting legumes of the Viciae and Cicerae tribes and pathogenicity of an interspecific hybrid. Phytopathology 96:1148-1156
  41. Chilvers, M.I., Hay, F.S., Hills, J., Dennis, J.J.C., and Wilson, C.R. 2006. Influence of benzimidazole fungicides on incidence of Botrytis allii infection of onion leaves and subsequent incidence of onion neck rot in storage in Tasmania, Australia. Australian Journal of Experimental Agriculture 46:1661-1664
  42. Chilvers, M.I., Pethybridge, S.J. and Hay, F.S. 2004. Characterisation of Botrytis species associated with neck rot of onion in Australia. Australasian Plant Pathology 33:29-32
  43. Chilvers, M.I., Hay, S. and Wilson, C.R. 2004. Survey for Botrytis species associated with onion bulb rot in northern Tasmania, Australia. Australasian Plant Pathology 33:419-422

 

REFEREED REPORTS, PLANT DISEASE NOTES, BOOKS and EDITORIALS

  1. Byrne, A.M., Chilvers, M.I. Breunig, Olson, E., Siler, L. 2017. Effect of fungicides on performance of winter wheat in Michigan, 2016. Plant Disease Management Reports 11:FC029
  2. Byrne, A.M., Chilvers, M.I. Efficacy of foliar fungicides for white mold management of soybean in 2016a. Plant Disease Management Reports 11:FC030
  3. Byrne, A.M., Chilvers, M.I. Efficacy of foliar fungicides for white mold management of soybean in 2016b. Plant Disease Management Reports 11:FC029
  4. Breunig, M., Byrne, A.M., Chilvers, M.I., Nagelkirk, M. 2017 Effects of post-flowering applications of fungicides on stripe rust control and performance of winter wheat, 2016. Plant Disease Management Reports 11:CF027
  5. Byrne, A.M., Chilvers, M.I., Widdicombe, W., Williams, L. 2017 Effect of fungicides and insecticides on the performance of corn in Michigan, 2016. Plant Disease Management Reports 11:FC021
  6. A farmer’s guide to corn diseases. Chilvers, M.I. et al., contributing author. Edited by Wise, K., Mueller, D., Sisson, A., Smith, D., Bradley, C., Robertson, A.
  7. A farmer’s guide to soybean diseases. Chilvers, M.I. et al., contributing author. Edited by Mueller, D., Wise, K., Sisson, A., Smith, D., Sikora, E., Bradley, C., Robertson, A.
  8. Byrne, A.M., Chilvers, M.I., Widdicombe, W., Williams, L. 2016. Effect of fungicides on the performance of corn in Michigan, 2015. Plant Disease Management Reports 10:FC054
  9. Chilvers, M.I., Byrne, A.M. 2016. Efficacy of foliar fungicides for brown spot control in Michigan soybeans, 2015. Plant Disease Management Reports 10:FC024
  10. Chilvers, M.I., Byrne, A.M., Olson, E., Siler, L. 2016 Effect of fungicides and nutrient amendments on the performance of winter wheat, 2015. Plant Disease Management Reports 10:CF033
  11. Chilvers, M.I. and Byrne, A.M., Efficacy of foliar fungicides for white mold management in Michigan soybeans, 2015. Plant Disease Management Reports 10:FC023
  12. Habibi, A., Peever, T., Chilvers, M.I., Kaiser, W., Muehlbauer, F. 2015. First report of Ascochyta blight of spotted locoweed (Astragalus lentiginosus) in Idaho caused by Ascochyta Plant Disease 99:1446
  13. Byrne A.M., Chilvers, M.I., Dietz, T.S., Johnson, K. 2015. Efficacy of foliar fungicides for brown spot in Michigan soybeans, 2014. Plant Disease Management Reports 9:FC026
  14. Byrne A.M., Chilvers, M.I., Dietz, T.S., Johnson, K. 2015. Effect of fungicides on the performance of corn in Michigan, 2014. Plant Disease Management Reports 9:FC054
  15. Byrne, A., Chilvers, M.I. Efficacy of foliar fungicides for white mold management in Michigan soybeans, 2014. Plant Disease Management Reports 9:FC055
  16. Nagelkirk, M.L., Chilvers, M.I., Byrne, A.M. 2015. Effect of fungicides on the performance of winter wheat, 2014. Plant Disease Management Reports 9:CF028
  17. Chilvers, M.I. Contributor/reviewer for: Michigan pesticide training manual
  18. Mollov, D., Chilvers, M.I., and Jacobs J.L. 2014 First report of aster yellows phytoplasma in soybean in Michigan. Plant Disease 98:1578.1
  19. Chilvers, M.I. In: Compendium of Soybean Diseases. APS Press. Author for revised section. – submitted Apr-11-14.
  20. Byrne A.M. and Chilvers, M.I. Efficacy of foliar fungicides for white mold control in soybeans in Michigan, 2013. Plant Disease Management Reports 8:FC174.
  21. Byrne A.M., Chilvers, M.I., Serven, B.L. and Dietz, T.S. 2014. Foliar fungicide efficacy on brown spot of soybeans in Michigan, 2013. Plant Disease Management Reports 8:FC175.
  22. Jacobs, J.L. and Chilvers, M.I. 2013. First report of Soybean vein necrosis virus on soybeans in Michigan. Plant Disease 97:1387.
  23. Chilvers, M.I. and Serven, B.L. 2013. Foliar fungicide efficacy on brown spot of soybeans in Michigan, 2012. Plant Disease Management Reports 7:FC037.
  24. Mueller, D., Wise, K., Dufalt, N., Bradley, C. and Chilvers, M.I. (Edited) 2013. Fungicides for Field Crops. APS Press. 120 pages.
  25. Chilvers, M.I. Molecular diagnostics in plant disease diagnostic clinics…what’s the status? (Editorial) Fungal Genomics and Biology. 2:e102. doi:10.4172/2165-8056.1000e102
  26. Chilvers, M.I., Warner, F.W., Jacobs, J.L. and Wang, J. 2012. Efficacy of nematicide and fungicide seed treatments for soybean cyst nematode and soybean sudden death syndrome in Michigan, 2011. Plant Disease Management Reports. 6:ST003
  27. Chilvers, M.I., Jacobs, J.L. and Boyse, J.F. 2012 2012. Triazole foliar fungicide efficacy on Septoria brown spot in soybeans in Michigan, 2011. Plant Disease Management Reports. 6:FC026
  28. Chilvers, MI., Zehr, G.L. and Munoz, J.D. 2011. Foliar fungicide efficacy on brown spot in soybeans in Michigan, 2010. Plant Disease Management Reports. 5:FC006.
  29. Chilvers, M.I. and Brown-Rytlewski, D.E. 2010. First report and confirmed distribution of soybean sudden death syndrome caused by Fusarium virguliforme in southern Michigan. Plant Disease 94:1164.
  30. Abang, M.M., Kabbabeh, S., Ahmed, S., Murad, S., Chilvers M.I., Peever, T.L., and Schroers, H.-J. 2009. First report of chickpea wilt caused by Clonostachys rhizophaga in Syria. Plant Disease 93:666.
  31. Akamatsu, H.O., Chilvers, M.I. and Peever, T.L. 2008. First report of spring black stem and leaf spot of Medicago sativa (Alfalfa) in Washington state caused by Phoma medicaginis. Plant Disease 92:833.
  32. Chilvers, M.I., Horton, T.L., Peever, T.L., Kaiser, W.J., and Muehlbauer, F.J. 2007. First report of Ascochyta blight of Pisum elatius (wild pea) in the Republic of Georgia caused by Ascochyta pisi. Plant Disease 91:326.
  33. Chilvers, M.I., Horton, T.L., Peever, T.L., Kaiser, W.J., and Muehlbauer, F.J. 2006. First report of Ascochyta blight of Vicia hirsuta (Hairy tare) in the Republic of Georgia caused by Ascochyta Plant Disease 90:1555.