Molecular Characterization of Mycosphaerella Berkeleyi Causing Late Leaf Spot of Groundnut in Nghe An

Abstract

   This study identified the ITS (Internal Transcribed Spacer) sequence of 11 groundnut late leaf spot fungal isolates collected from Vietnam, mainly from Nghe An province in 2013. The ITS sequences of the 11 isolates were identical among them and highly identical (99.7 and 100%) with two available isolates of Mycosphaerella berkeleyi on the GenBank. Rep-PCR technique (Repetitive sequence primed PCR) with 3 sets of primers designed on the repetitive sequences of bacterial genome including the repetitive extragenic palindromic (REP) sequence, enterobacterial repetitive intergenic consensus (ERIC) and BOX element, was used to investigate the genetic diversity of 33 M. berkeleyi isolates. PCR using BOX primers (BOX-PCR) produced polymorphic bands from tested fungal isolates. Rep-PCR analysis proved that fungal populations in Nghe An were of low genetic diversity. There was no correlation between Rep-PCR defined fugal groups with the origin of the isolates (location of sampling, groundnut cultivars) and morphological characteristics of the isolates (color and size of cultures).