Keywords: Jaccard similarity, Isozyme banding pattern, SDS-PAGE, UPGMA, Zymogram
The present research work has been carried out for investigation of genetic diversity and phenetic relationship among nine Bangladeshi cultivars of cucumber (Cucumis sativus L.) using some isozymes and protein profiling by SDS-PAGE. Seventeen isozymes including acid phosphatase (ACP), alcohol dehydrogenase (ADH), alkaline phosphatase (ALP), amino peptidase (AMP), aspartate amino transferase (AAT), β-galactosidase (GAL), β-glucosidase (GLU), catalase (CAT), esterases (EST), formate dehydrogenase (FDH), fructose bisphosphatase (FBP), fumarate hydratase (FUM), hexokinase (HEX), malate dehydrogenase (MDH-NAD+), peroxidase (PRX), superoxide dismutase (SOD) and tyrosinase (TYR) were assayed. A total of 48 bands were detected resolved in 17 isozymes, out of which 21 were polymorphic. No polymorphism has been found in acid phosphatase, β-galactosidase, formate dehydrogenase, fumarate hydratase and peroxidase. A total of 23 protein bands were resolved, out of which 22 were polymorphic. Seven isozymes banding patterns were observed in Superoxide dismutase which was the highest among the 17 enzyme systems. Dendrograms and three-dimensional plots based on isozymes, SDS-PAGE and combined dataset clearly separated almost all the cultivars. From the phonetic analysis, it was revealed that the cultivars ‘Alavy-1’, ‘Baromasse’, ‘Raj-1’ and ‘Dinajpuri’ are somewhat more closely related than the other cultivars. The cultivar ‘Green king’ produced six cultivar specific bands in SDS-PAGE. This study will help successful breeding programmes in cucumber in Bangladesh.
Financial supports from United States Department of Agriculture (USDA), USA and Ministry of Education (MoE), Bangladesh are greatly acknowledged. The support and encouragement of the Principal, Vivekananda College, Thakurpukur, West Bengal, India is also greatly acknowledged. Useful comments from two anonymous reviewers are also acknowledged.