Graduate Students Complete Their Masters Programs
Staci Lynne Koberstein recently completed the requirement for an M.S. degree in plant pathology at Washington State University. Her thesis was entitled “Molecular marker identification in Oculimacula yallundae using next-generation sequencing.” Her thesis committee consisted of Timothy Murray (chair), Tobin Peever, Weidong Chen, Deven See, and Daniel Skinner. Oculimacula yallundae is a fungal pathogen causing eyespot or strawbreaker foot rot on cereal crops. Koberstein identified 2,018 simple sequence repeat (SSR) loci in isolate 90-45-7 and 2,020 SSR loci in isolate 90-49-1 of O. yallundae. She designed primers for 33 loci that were polymorphic between the two isolates, with which she made a cross, and identified 10 unlinked loci segregating at a 1:1 ration in the progeny population. These SSR markers are useful in studying the origin, migration patterns, and diversity of this pathogen. Koberstein grew up in Gig Harbor, Washington and received a B.A. degree in biology from Gonzaga University in 2012. She hopes to find a job related to fungal genetics.
Spencer H. Marshall recently completed the requirement for an M.S. degree in plant pathology at Washington State University (WSU). His committee consisted of Naidu Rayapati (Chair), Dennis Johnson, and Scott Adkins (USDA-ARS, Fort Pierce, Florida). Marshall’s thesis was titled “Genetic diversity of Tomato spotted wilt virus.” Tomato spotted wilt virus (TSWV) causes economically important diseases in a wide range of agricultural and horticultural crops worldwide. His studies found a greater genetic diversity of TSWV than previously shown within the US and laid the foundation to further elucidate genome-wide genetic diversity and molecular epidemiology of TSWV. Marshall received the Thrips Tospoviruses Educational Network Fellow scholarship to attend the 10th International Symposium on Thysanoptera and Tospoviruses, May 16-20, 2015, Asilomar, CA.
Stacy Mauzey recently completed the requirement for an M.S. degree in plant pathology at Washington State University (WSU). Her thesis was entitled “Characterization of Rathayibacter agropyri, a bacterial pathogen of Agropyron smithii,” and the study was under the supervision of Timothy Murray and Brenda Schroeder. The genus Rathayibacter was first described in 1993 and currently contains six species, which cause obscure diseases on a variety of grass and cereal hosts. In 2011, bacteria were isolated from herbarium samples of Agropyron spp. collected in 1945 and stored in the WSU Mycological Herbarium at Pullman. Mauzey cultured slow growing, yellow-pigmented bacterial colonies from the historical plant samples. She amplified the 16S rRNA gene from the cultured bacteria, sequenced, and compared to the 16S rRNA gene sequences of bacteria isolated from the same samples in 1982, as well as to other bacteria in the family Microbacteriaceae. Based on the 16S rRNA gene sequences and various biochemical and molecular analyses, she placed the bacterial strains in the genus Rathayibacter and identified the newly isolated strains constituting a novel species named Rathayibacter agropyri sp. nov. Additionally, her recovery of viable R. agropyri from 66-year-old plant samples is the longest known survival of a plant pathogenic bacterium in a natural sample. Mauzey received the 2013 National Science Foundation Graduate Research Fellowship, and a travel award to present her research on the genus Rathayibacter at the 60th Annual Conference on Soilborne Plant Pathogens in March, 2014 at the Dominican University of California in San Rafael.