|Goodwin, Stephen - Steve|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 5/10/2010
Publication Date: 6/10/2010
Citation: Gurung, S., Goodwin, S.B., Kabbage, M., Bockus, W., Adhikari, T.B. 2010. Analysis of Mycosphaerella Graminicola from California, Indiana, Kansas and North Dakota with Mating Type and SSR Markers. Phytopathology. 100:S45. Interpretive Summary:
Technical Abstract: Septoria tritici blotch, caused by Mycosphaerella graminicola, is one of the most important foliar diseases of wheat. Genetic diversity of 333 isolates of M. graminicola collected from spring (California, North Dakota) and winter wheat (Indiana, Kansas) was analyzed for mating type and 17 SSR markers. The Indiana, Kansas, and North Dakota populations were further subdivided into two, six, and two subpopulations respectively according to sampling sites and years of collection. Clone-corrected data analysis revealed that both mating types were distributed in a 1:1 ratio in the Kansas, Indiana and North Dakota populations, but deviated from 1:1 in the California population. Gene diversity values for the California, Indiana, Kansas, and North Dakota populations were 0.44, 0.53, 0.40, and 0.57, respectively. No evidence of linkage disequilibrium was observed in all populations or subpopulations analyzed. High gene flow was observed between the California and Kansas (Nm = 15.914) and Indiana and Kansas (Nm = 16.89) populations. Analysis of molecular variance showed that most genetic variation (> 82%) was within populations and subpopulations; less than 18% occurred between the populations or subpopulations. Taken together, these results indicate that frequent sexual recombination occurs in M. graminicola populations in spring and winter wheat. Furthermore, all geographically separated populations of M. graminicola are genetically similar, suggesting a panmictic structure.