Genetic variation and mating type distribution of Rhynchosporium commune in Turkey

摘要

Rhynchosporium commune is the causal agent of barley scald disease and is an important foliar disease of barley worldwide. During 2012, 2013, and 2014, Rhynchosporium commune single-spore isolates were collected from different parts of Turkey, and from those, 60 isolates were selected. The mating type distribution and prevalence of these selected isolates were determined. Twenty-one of the 60 single-spore isolates were found to be MAT1-1 type and 39 isolates were MAT1-2 type chi 2 (1:1) types = 5.40 (P = 0.02). The mating type ratio showed that R. commune populations may have predominantly asexual reproduction in Turkey. To determine the genetic diversity of R. commune isolates, 5 single-spore isolates from different regions of Turkey were tested with 72 ISSR primers. Eleven primers were found to be polymorphic. UBC 826, UBC 861, UBC 886, UBC 887, UBC 890, UBC 848, UBC 884 and UBC 850 primers showed optimal band numbers and good band intensities. Sixty isolates were evaluated with these 8 ISSR primers. UBC826 and UBC886 primers amplified the largest numbers of bands. The genetic diversity of the isolates in the R. commune population in Turkey appeared to be low. There were no definite groupings of the mating type or geographical region. Turkey is one of the gene centers of barley and this study is the first one addressing the genetic variation and mating type distribution of R. commune in Turkey. The low genetic diversity and possible asexual reproduction observed in our study may contribute to the hypothesis that R. commune did not evolve in the origin of the barley plant.