Identification of hyperparasitic fungus Erysiphe diffusa causing powdery mildew on soybean in Vinh Phuc, Vietnam

Abstract

Hyperparasitic fungus Erysiphe diffusa Cooke & Peck 2000, which causes powdery mildew on soybean (Glycine max (L) Merr) cultivated in Vinh Phuc province, has been identified by the combination of molecular biotechnology and standard morphological classification of Braun and Cook 2012 as well as being confirmed by pathogenicity test fulfiling Koch’s postulate. Six sequences of ITS rRNA region of this fungus on soybean have been registered in the GenBank with Accession numbers including KM260706 and from KM260708 to KM260712. The disease appeared on soybean cultivated in Vinh Phuc during winter-spring crop 2013-2014, reached the peak at the beginning of April with the highest disease incidence 22% and disease severity 9.5%.