Research Article
Purnima Dey, Ismail Hossain
Abstract
Bacterial wilt (Ralstonia solanacearum) is the most destructive disease in solanaceous crops that is threatened to brinjal production with other crops. The 12 isolates of R. solanacearum on seeds of brinjal with different seed sources in Bangladesh were studied to determine the genetic variability on Random amplified polymorphic DNA (RAPD) with OPA18 marker. The highest bacterial infection (93.00%) was obtained with seeds of isolate Al-Amin Beez Vander while the lowest (14.00%) was in Metal seed company Ltd. In molecular level, the 17 bands (100%) of the 17 distinct bands were revealed as polymorphic. Dendrogram based on Nei’s (1972) genetic distance of unweighted pair group method with arithmetic means segregated the isolates of R. solanacearum in two main clusters, as cluster 1 of Metal seed company Ltd. isolate, ACI seed company Ltd. and the isolate of Krishan agro seed company Ltd. were formed and rest of the 12 isolates were belonged to cluster 2. Isolate of Krishan Agro Service was very close to BARI Begun-1 (harvested seed sample) with the least genetic distance (0). Krishan Agro Service was found to have near between the isolates of BARI Begun-1 and Islamia Beez Vander with low genetic distance (0.125) which was close to the Yasin Beez Vander observed in same group with the low genetic distance (0.125). Coefficient of gene differentiation was 1.0000 which showed the highest genetic variations among the isolates of R. solanacearum. The highest genetic distance (1.447) was marked in Krishan Agro seed company Ltd. vs. Bismillah Beez Vander and the lowest genetic distance (0.000) was estimated in Krishan Agro Service vs. BARI Begun-1. The highest (1.000) genetic identity was found in BARI Begun-1 vs. Krishan Agro Service, while the lowest genetic identity (0.2353) was noted between the isolate of Bismillah Beez Vander vs. Krishan Agro seed company Ltd. The genetic variation of R. solanacearum in 12 isolates of brinjal seeds varied significantly in their respective location and the individual isolate was not found to be indicated as the host specific with each other.