INVESTIGATING MA T HETEROKARYONS IN ISOLATES OF Sclerotinia sclerotiorumIN BRAZIL

摘要

Sclerotinia sclerotiorum is an important pathogen of common bean. It is a homothallic fungus (self-compatible) and the resulting population is expected to be clonal with limited variability (Billiard et al. 2012), but high genetic variability has beenreported (Abreu and Souza, 2015). It has been recently found that S. sclerotiorum has peculiar MAT alleles for a homothallic species (Chitrampalam et al. 2013). Two MAT alleles are responsible: inversion positive (Inv+) and inversion negative (Inv-). Besides that, 5". sclerotiorum is a multinucleate fungus, and is known to form heterokaryons under nonrestrictive conditions. Heterokaryons were detected in some isolates by Chitrampalam et al. (2015), providing another possibility of outcrossing. There isno information about this in S. sclerotiorum isolates from Brazil. Sample of isolates from Brazil were assessed to verify presence of MAT homokaryon Inv+ or Inv- and MAT heterokaryons.