Studies on Genetic Relationships among Cultivated and Wild Sunflowers through RAPD Markers

Abstract

Random Amplified Polymorphic DNA (RAPD) markers were employed to study the genetic relationships between cultivated sunflower and selected wild sunflower species. Of the 40 random primers screened, 21 primers resulted in good amplification. The data structure included a total of 140 marker levels for 18 genotypes involving accessions of cultivated sunflower, wild sunflower species of different ploidy levels and a few interspecific hybrids. Squared Euclidean distance between individual genotypes was calculated and the genotypes were clustered following Unweighted Pair Group Method with Arithmetical Averages (UPGMA). The dendrogram showed 3 distinct clusters namely cultivated genotypes, interspecific hybrids and their parents, and perennial diploid, tetraploid and hexaploid sunflowers. The pattern of clustering was in line with the current taxonomy of sunflowers. Further, it was observed that increase in genetic distance between the cultivated and wild sunflowers seems to reflect an associated decrease in crossability between them. However, further studies are required in this direction.