Interrelationships Among Species of Dioscorea Revealed by Morphological Traits and RAPD Markers

This present study assessed the interrelationships among the 12 species of Dimscorea by morphological traits and RAPD analysis using 14 decamer primers. In the molecular profiling of the 12 species of Dioscorea a total of 133 amplified products were obtained. Of the 133 amplified products all were found to be polymorphic showing high degree of genetic variability between species of Dioscorea. Morphologically related species such as D. oppositifolia, D. spicata and D. wightii got separated in RAPD analysis. Moreover, both RAPD and morphology separated D. hispida of the Section Lasiophyton from the other two species such as D. pentaphylla and D. tomentosa. Out of the 12 species studied, 9 species were grouped into 2 clusters and D. bulbifera remained as a separate entity. The results were in agreement with the earlier classification except D. hispida and D. pubera, which remained as distinct entities from the rest. But on the basis of RAPD data, nine species were grouped into two major clusters with each species showing distinct genetic distance with others, while the rest of the three D. hispida, D. oppositifolia and D. wightii remained as separate entities.