Plant Pathology-Research

High Tunnels

Programs and Staff

Dr. Charles M. Rush has a 100% research appointment with Texas A&M AgriLife Research in Amarillo. He established his laboratory in 1986 to conduct research on economically important diseases of crops produced in the Texas Panhandle. Dr. Rush is a Professor in the Department of Plant Pathology and Microbiology and a Faculty Fellow and Regents Fellow with A&M AgriLife Research and Texas A&M University. He also serves as Adjunct Professor with West Texas A&M University and Texas Tech University, and is a Fellow in the American Phytopathological Society.

Goal: To provide leadership in addressing emerging and long-term plant disease problems of regional and national importance, by conducting research with relevance to immediate needs.

Programmatic Research Focus: Ecology and epidemiology of economically important plant pathogens and their vectors. The lab is currently working on three major disease problems:

Mite Vectored Virus Diseases of Wheat – Wheat streak mosaic and Triticum mosaic:
Diseases caused by mite-vectored viruses are the major biotic constraint to sustainable wheat production in the western Great Plains. Using a variety of remote sensing techniques for disease detection, and integrating disease loss estimates with an economic analysis, we found that losses to mite-vectored virus diseases exceeded $10 million in Deaf Smith County in 2008. We also have shown that WSMV negatively impacts root function and crop water use efficiency in wheat and that populations of TriMV are genetically homogeneous and stable. Priority research areas include:
• Wheat curl mite population dynamics – In collaboration with Dr. Jerry Michels, Texas A&M AgriLife
• Population diversity of Triticum mosaic virus – In collaboration with Dr. John Fellers, KSU
• Genetics of resistance to WSMV – In collaboration with Drs. Jackie Rudd and Huangjun Lu, Texas A&M AgriLife
• Wheat Virus Early Detection System

Funding Sources: Cropping Systems Initiative, Texas Wheat Producers, and National Plant Diagnostics Network (Approximate total: $450,000, 2009–2011); Invited to submit full proposal to NHARP Program.

Fungal Vectored Virus Diseases of Sugar Beet – Rhizomania
Beet necrotic yellow vein virus, vectored by Polymyxa betae, causes rhizomania, the most economically important disease of sugar beet worldwide. We recently reported that strength of genetic resistance was positively correlated to mutation frequency in BNYVV RNA 3 and that this could lead to rapid emergence of new resistance breaking (RB) strains. This hypothesis was verified this season with emergence of new RB strains of BNYVV that overcame Rz2 genetic resistance in sugar beet. Furthermore, the mutation in BNYVV associated with overcoming Rz1 resistance is not present in Rz2 RB strains of BNYVV. Priority research areas include:
• Beet necrotic yellow vein virus population genetics
• Evolution of resistance breaking strains of BNYVV
• Virus/vector interactions
• Benyvirus strain/species competition

Funding Sources: USDA-NIFA, Beet Sugar Development Foundation, Minnesota/North Dakota Research and Education Board (Approximate total: $625,000, 2009–2012)

Zebra Chip (ZC) of Potato
Zebra Chip is an emerging disease of all classes of potato, and is putatively caused by Candidatus Liberibacter solanacearum, which is vectored by the potato psyllid. It cost Texas producers and processors millions of dollars in 2005–2008, when the disease reached epidemic levels. In 2009, we demonstrated that early psyllid infestations disproportionately occur on the edge of fields and that disease progression rapidly drops off approximately three weeks after flowering. These results will contribute to better disease management strategies and reduced pesticide applications. Although Dr. Rush only began working on ZC in June 2007, he has already taken a national leadership role by writing a successful Specialty Crop Research Initiative proposal and serving as the ZC SCRI Program Director. Priority research areas include:
• Temporal and spatial dynamics of the potato psyllid
• Disease forecasting and risk assessment
• Host/pathogen/vector interactions – In collaboration with Dr. Joe Munyaneza, USDA-ARS, WA

Proceedings of the 10th Annual SCRI Zebra Chip Reporting Session
Proceedings of the 11th Annual SCRI Zebra Chip Reporting Session
Proceedings of the 12th Annual SCRI Zebra Chip Reporting Session
Proceedings of the 13th Annual SCRI Zebra Chip Reporting Session
Proceedings of the 14th Annual SCRI Zebra Chip Reporting Session

Funding Sources: Specialty Crop Research Initiative, Texas Zebra Chip Initiative (ZC SCRI $6.7 M for all collaborators, 2009 – 2014; TX ZC Initiative $120,000, 2010 – 2011)

Service Activities: Although Dr. Rush has no official extension responsibilities, he has provided plant disease diagnostic services since his lab’s inception. This resulted in his lab being designated as a member of the Great Plains Diagnostic Network (GPDN) in 2002. His current association with the GPDN relates to development of new techniques for pathogen and disease detection and quantification.

Senior Research Personnel: