Molecular detection and genetic characterisation of fumonisin producingfusariumisolates from rice cultivars

Abstract

Fusarium species mainly produce fumonisins group of mycotoxins which are classified as Group 2B human carcinogen by International Agency for Research on Cancer (IARC). In poor storage conditions, Fusarium species producing fumonisins can infect rice or paddy (Oryza sativa L.) which is the highest produced and consumed staple food in India. A rapid molecular method using primer Fum5F and Fum6R detected 85% fumonisin producers among 28 Fusarium isolates from Indian rice cultivars. Genetic variability of the isolates was studied by PCR based RAPD assay using 13 random primers. A total of 169 polymorphic bands were obtained by 13 markers with an average polymorphism information content (PIC) of 0.665 and overall polymorphism of 88%. Primer 3B showed a polymorphism of 96% with PIC value of 0.66 and it amplified 26 scorable fragments hence may be useful for the analysis of genetic variation among Fusarium isolates. Four strains (F47, F90, F92 and F96) in which fum gene wasn't amplified by Fum5F and Fum6R and supposed to be non producer of fumonisin have been consistently placed in one separate group by RAPD primers. Genetic variation of toxic Fusarium in rice from India is less studied. RAPD proved to be a suitable tool for depicting Polymorphism among the isolates. The high genetic variability among the Fusarium isolates used in the current study is a matter of concern considering the importance of Rice in India.