Characterizing morphological and genetic variation of soil fungal pathogen Rhizoctonia solani
Conference Year
January 2020
Abstract
Rhizoctonia solani is a soilborne fungal pathogen that targets crops such as lettuce and potato. Between 30-50% of a lettuce crop is lost to R. solani in Vermont. There is limited information regarding specific strains (anastomosis groups (AG)) of R. solani in Vermont. Obtaining AG groups is essential to combat this disease with effective control strategies. In this study, 31 Vermont vegetable farms were sampled to determine the cause of lettuce and potato rot. R. solani was isolated from diseased tissue samples and by baiting with radishes. Isolates were obtained from 16 of the 31 farms. The hyphal branching was examined under a microscope to make an initial determination of R. solani, and a catalog was created with photographs of colony and branching patterns for each isolate. Among the Rhizoctonia colonies, variations such as differences in hyphal cell shape were seen; some were more beaded and others were more linear. Sclerotia formation and colony color also differed among isolates. A representative sample size of 20 isolates was chosen for a polymerase chain reaction (PCR) to determine specific AG groups. Isolates representing three large Vermont lettuce growers serve as a reference to develop selective media as diagnostic tools.
Primary Faculty Mentor Name
Deborah Neher
Secondary Mentor Name
Thomas Weicht
Graduate Student Mentors
Tucker Andrews
Faculty/Staff Collaborators
Dr. Deborah Neher (Faculty Advisor), Thomas Weicht (Senior Technician), Tucker Andrews (Graduate Student)
Status
Undergraduate
Student College
Rubenstein School of Environmental and Natural Resources
Program/Major
Wildlife and Fisheries Biology
Primary Research Category
Biological Sciences
Characterizing morphological and genetic variation of soil fungal pathogen Rhizoctonia solani
Rhizoctonia solani is a soilborne fungal pathogen that targets crops such as lettuce and potato. Between 30-50% of a lettuce crop is lost to R. solani in Vermont. There is limited information regarding specific strains (anastomosis groups (AG)) of R. solani in Vermont. Obtaining AG groups is essential to combat this disease with effective control strategies. In this study, 31 Vermont vegetable farms were sampled to determine the cause of lettuce and potato rot. R. solani was isolated from diseased tissue samples and by baiting with radishes. Isolates were obtained from 16 of the 31 farms. The hyphal branching was examined under a microscope to make an initial determination of R. solani, and a catalog was created with photographs of colony and branching patterns for each isolate. Among the Rhizoctonia colonies, variations such as differences in hyphal cell shape were seen; some were more beaded and others were more linear. Sclerotia formation and colony color also differed among isolates. A representative sample size of 20 isolates was chosen for a polymerase chain reaction (PCR) to determine specific AG groups. Isolates representing three large Vermont lettuce growers serve as a reference to develop selective media as diagnostic tools.