The 2012 ASHS Annual Conference

Knowledge of genetic variability of Mycosphaerella fijiensis is important for understanding the biology of populations. This information can help us to predict the evolutionary potential of populations and establish more efficient strategies to control and the disease. In Mexico, M. fijiensis was found for first time in the States of Chiapas and Tabasco in 1981, while in the State of Colima was identified in 1989, followed by Michoacan in next year. The aim of this study was to determine the genetic variability of 83 isolates of M. fijiensis from regions of the Colima, Jalisco, Michoacan, Tabasco and Chiapas States; for this goal it was conducted the analysis of 10 SSR loci. The results have demonstrated an average of 3 alleles by locus, and has been identified a total of 30 alleles. A percentage of 96.6% of polymorphic alleles were obtained. It was found 5 alleles in the locus MfSSR41, whereas MfSSR306, MfSSR333 and MfSSR315 loci showed 2 alleles each. The dendrogram showed four groups; Group I included isolates from Colima (20 isolates), which showed a genetic similarity of 1.0. Group II comprised six isolates from Tabasco and nine of Michoacan. Group III consisted of 12 from Michoacan and 2 from Chiapas, the latter are genetically less similar. Group IV was comprised of 20 of Chiapas and Tabasco 14. The clusters show genetic variability. There was genetic variability among isolates of Colima, whereas if there between Michoacan. The more isolated genetically variable could adapt more quickly to host resistance or fungicides. This work is being funded by FORDECyT-CONACyT contract No. 116886