Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Genetic Diversity of Perennial Weedy Ipomoea sp L. as. Wild Progenitor for Sweet Potato Ipomoea batatas L.

Wild relative of sweet potato i.e. I. trifida, I. cairica and I. triloba originated from district Citatah in West Java are known as perennial weedy plants. However, these weeds are considered as potentially useful in breeding program to complement the special traits of cultivated-sweet potato. These perennial weeds carry genes for stress tolerance and/or resistance. For example, I. triloba has drought tolerance genes, I. cairica has virus resistance genes, while I. trifida has short duration characteristics. However, information in the genetic diversity and its relationships between the wild and cultivated Ipomoea is important due to breeding program. The objective of this research was to estimate the genetic diversity and the relation of 148 accessions of perennial weedy genus Ipomoea collected from Citatah West Java based on 29 morphological traits. Principal component analysis was employed to estimate the genetic diversity and to determine the relationship within the genus. The results indicated that dissimilarity coefficients were ranged between 0.00 to 5.60, and therefore they are considered as a high variation in the accessions studied. Furthermore, 2 clusters have been clearly observed, i.e. cluster A and B. Cluster A consists of 2 sub-clusters, i.e., A1 and A2. In sub-cluster A1 consisting of 145 accessions, most accessions gathered in cluster A1 (145 accessions). Cluster A2 consisted of 2 accessions of accession no 22 and no 169. Cluster B consists only one (accession no 41P) that have the greatest dissimilarity distance of 5.60. The morphological traits which played significant role as the determinant of the diversity were predominant vine colour, secondary vine colour, vine type pubescens, leaf lobus type, shape of central leaf lobe, abaxial leaf vein, pigmentation, mature leaf colour, petiole pigmentation, shape of limb, equality of sepal length, sepal shape, sepal apex, colour of stigma and stigma exertion. The pattern of the relations between the accessions of perennial weedy plants of wild Ipomoea can be used as base information for further sweet potato breeding program in the near future.