Mating-Type Analysis in Isolates from Soybean in Central Europe.

Species of the genus have a mating-type system with the two mating types MAT1-1 and MAT1-2, like other ascomycetes. They can either be heterothallic, which means that any isolate only possesses one of the two mating types and needs a mating partner for sexual reproduction, or homothallic, which means that they possess both mating types and are self-fertile. For several species, no sexual reproduction has been observed so far. Using PCR with primers specific to the defining genes and , we determined the mating types of 33 isolates of , , , and from central Europe. In addition, we partially sequenced the mating-type genes of 25 isolates. We found that different isolates either possess or making the species heterothallic, which is in contrast to previous studies and the general assumption that only reproduces asexually. and were also found to be heterothallic. Using genomic sequence information and re-sequencing of DNA and RNA, we identified the gene in and present here the full sequence of the mating-type locus of this homothallic species. Finally, we used sequence information from and , respectively, for improved phylogenetic resolution of our isolates.