Phylogenetic relationship of ten ipomoea jacq. species based on proteins and isozyme analysis

The genotype of an organism expresses itself through the phenotype that is through proteins. Protein molecular markers provide indirect information about plant genome structure. Quantitative estimation of protein content from germinating seedlings was performed by Lowry assay. Total soluble protein analysis of all the species of Ipomoea under study was carried out by Native PAGE and SDS-PAGE, followed by isozyme analysis for Esterases (EST), Peroxidases (POX), Malate dehydrogenase (MDH), Ribulose bis-phosphate carboxylase-oxygenase (RUBISCO). The genetic similarity matrix was calculated using Jaccard’s co efficient and the dendrogram was constructed using UPGMA. None of the ten species showed identical bands in the electrophoretic leaf protein banding pattern on SDS PAGE. On the basis of similarity index of Esterases isozyme analysis I. aquatica and I. quamoclit showed 100% affinity, while I. triloba and I. violacea exhibited minimum similarity with all the ten species. On the basis of similarity index Peroxidases isozyme analysis I. hederifolia and I.turbinata exhibited minimum similarity of 25%. The cluster analysis based on the combination of total soluble Proteins and the four isoenzymes showed that I. pes-caprae and I. carnea are closest with maximum similarity of 77.8%, whereas I. quamoclit and I. violacea has least similarity of 42.3%.