Tomato Seed Borne Ralstonia solanacearum in Bangladesh

Genetic diversity of Ralstonia solanacearum , on seeds of tomato from different seed sources in Bangladesh was studied by using Random amplified polymorphic DNA (RAPD) markers. The primers viz., OPA02, OPA08, OPA09, OPA10, OPA18 and OPE19 were tested in this experiment and were also evaluated on the basis of intensity and resolution of the band. Of these, the specific marker (OPA18) of RAPD in molecular characterisation of R. solanacearum produced distinct twenty bands with 100% polymorphism at base pair of 100–2000. Segregation of isolates of R. solanacearum was determined in unweighted pair group method with arithmetic means. In cluster analysis, isolate of Metal seed company Ltd. was very near with United seed company limited and Mallika seed company with the least genetic distance. Metal seed company Ltd. was also close to Lal Teer seed company Ltd. with lower genetic distance (0.1625). Coefficient of gene differentiation (1.0000) in R. solanacearum marked high genetic variations indicating adequate polymorphism. The highest (1.204) genetic distance was found in Namdhari seed company limited vs. Bangladesh Institute of Nuclear Agriculture (BINA). Moreover genetic identity was obtained as higher (0.8500) in United seed company limited vs. Metal seed company Ltd., and the lowest genetic identity (0.3000) was noted in BINA vs. Namdhari seed company limited. Banding pattern, gene differentiation, genetic distance and genetic identity showed the distinct genetic variations which were associated with each isolate of R. solanacearum.