ASSESSMENT OF RESISTANCE TO THE TOMATO SPOTTED WILT VIRUS USING RAPD MARKERS

Genetic relatedness of ten (Lycopersicon esculentum Mill.) varieties was studied through RAPD analysis. Eight 10-mer oligonucleotide primers were used for PCR amplification. A total of 1327 amplified fragments with an average of 165.9 bands per primer. Among them, 194 were polymorphic with an average 19.4. Based on the banding patterns observed among the tomato varieties, the values of pairwise genetic relatedness ranged from (0.54) of Redcaript variety to (0.00) value between both 100/100 as resistance variety and Ghorsafi 6 as susceptible variety to tomato spotted wilt virus, indicating the presence of wide genetic relatedness. The dendrograrm constructed based on the phylogenetic relationship analysis revealed that the highest genetic relatedness was obtained between the 100/100 tomato variety and Redcarpit variety, whereas the lowest value recorded between the 100/100 and Ghorsafi variety. The dendrogram grouped the tomato varieties into three major clusters. The variety Top1199 was formed a separate cluster while the other varieties formed two clusters. RAPD markers are useful tool for assessing the genetic relatedness and diversity in tomato landraces and cultivars.