Genetic variation of high yielding drought resistant sweet potato as evident by RAPD markers

Abstract

Detailed agronomical analysis and random amplified polymorphic RAPD markers were used for determining the genetic diversity among ten varieties of sweet potato Ipomoea batatas L. Lam , one of the leading tuber crop belonging to the family Convolvulaceae. Varieties developed by Central Tuber Crops Institute, Trivandrum and its Regional Centre, Bhubaneswar with diverse parentage from diverse eco-geographical areas was analyzed for their genetic relationship. A total 1035 amplicons were generated among the ten varieties out of which ~79% bands were found polymorphic. Inter-varietal polymorphism among ten varieties of I. batatas varied between 60.0 to 89.7%. Clustering based on similarity index was done following Unweighted Pair Group with Arithmetic mean UPGA method and intra-genetic relationships were analysed. The resultant dendrogram of the RAPD data exhibited prominent patterns of inter-varietal relationships that are discussed in the light of the their physio-morphological characters. It was evident from RAPD data that high degree of genetic divergence exists only in var. Kalinga and var. Sourin; two pink skinned tuber producing varieties. However, no much genetic variation were found among var. ST-10, ST-13 and ST-14 except presence of 3000bp marker in ‘ST-14’ and 800bp marker in ‘ST-14’ and ‘ST-13’ besides their common marker of 900bp in all the studied varieties in OPD-12. Omission of 600bp and 700bp DNA bands in ‘ST-10’ differentiate with other ‘ST-13’ and ‘ST-14’ in OPN-4. ‘Kalinga’ and ‘Sourin’ showed more closer genetic affinity forming an out group from the rest of the varieties as per the phylogenetic tree is concerned. It suggests their adaptation in various conditions suitable for the specific habitat of particular varieties

Keywords

• Agronomic traits,Ipomea,RAPD markers,tuber crop,tuber yield

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