Genetic Variability in Fusarium oxysporum Isolates Causing Wilt of Tobacco Using RAPD Markers

摘要

Ten isolates of Fusarium oxysporum collected from wilt disease affected tobacco plants and other crops in the surrounding areas from northern light soils and traditional black soil areas of East and West Godavari districts of Andhra Pradesh were subjected to RAPD analysis. Seventeen primers generated a total of 135 bands in the size ranging from 0.2 to 2.8 kb with unique banding patterns depending upon primers and isolates. Polymorphism per primer ranged from 57 to 100%. Primers OPP1, OPP10, PL5, OPC10 and OPAB2 were cent per cent polymorphic and could be to study genetic diversity in Fusarium species. Based on RAPD profile, the pair-wise similarity coefficients for all isolates ranged from 0.17 to 0.89 with an average of 0.53. The isolates were grouped into two major clusters by UPGMA. Fusarium isolates of flue-cured tobacco were clustered separately from natu tobacco isolates. The isolate from Jatropha (FJ) was found to be the most divergent but linked to the main cluster. The high genetic variability among the various isolates of F. oxysporum from different hosts other than tobacco indicates their host specificity.