Genetic variability and relationship analysis of Bipolaris sorokiniana isolates causing spot blotch disease in wheat using random amplified polymorphic DNA (RAPD) markers

Abstract

Twelve (12) isolates of Bipolaris sorokiniana (Cochliobolus sativus) of wheat were studied for their molecular characterization using random amplified polymorphic DNA (RAPD) techniques. Twenty (20) RAPD primers were tested for amplification of the genomic DNA of fungal isolates of wheat. A total of 77 bands were amplified, out of which 68 bands were polymorphic showing high range of variability (84.42% polymorphism) and nine bands were monomorphic. Average total number of bands generated per primer was 3.85, of which 3.4 and 0.45 were polymorphic and monomorphic, respectively. The genetic similarity coefficients for the 12 isolates of B. sorokiniana of wheat ranged from 0.526 to 0.842. The highest similarity occurred between DWR-Karnal versus Hisar-PBW-443 and Hisar-502 versus IARI with a coefficient value of 84.2% and the lowest similarity occurred between two fungal isolates that is, Hisar-WH-542 versus IARI and Meerut-Hallana versus Faizabad with a coefficient value of 52.6%. The study indicates that the RAPD is a good tool for determination of genetic variability and relationship of B. sorokiniana, which is already visible in the analysis of even such a small number of isolates.

Keywords: Wheat, Bipolaris sorokiniana, genetic variability, polymorphism, random amplified polymorphic DNA (RAPD) marker

African Journal of Biotechnology Vol. 12(19), pp. 2526-2531