Molecular Analysis of the Genetic Diversity in Indonesian Sweetpotatoes
(M. Tanaka, H. Nakayama, Y. Takahata, M.J. Yakub, I.H. Somantri, Minantyorini, H. Kurniawan, M. Nakatani)
To contribute to the construction of an efficient strategy for on-farm genetic resource management, we investigated the genetic diversity of local sweetpotato (Ipomoea batatas) cultivars in Indonesia. We performed randomly amplified polymorphic DNA (RAPD) analysis using 190 Indonesian local cultivars collected from 14 collection sites, along with 23 cultivars from Japan, the Philippines, and Papua New Guinea. Using 14 arbitrary 12-mer primers, 50 polymorphic bands were obtained. Analysis of gene diversity suggested that genetic variation in local cultivars is partitioned within regional groups rather than between them. However, a principal coordinates analysis (PCOORDA) based on the genetic similarity indicated weak genetic differentiation between regional groups. Also, a cluster analysis indicated that the genetic relationship between regional groups is partially associated with the geographical relationship between collection sites. These results suggest the existence of geographical variations among the Indonesian cultivars. Comparison of gene diversity in each collection site suggested that cultivars in the northern part of Sulawesi Island had the highest degree of diversity among the regional groups analyzed.
Keywords: Ipomoea batatas, sweet potato, genetic resources, genetic diversity, geographical variation, RAPD, on-farm conservation