Abstract

Twelve released varieties of cassava and 24 central Kerala collections were assessed at the genomic DNA level with 36 SSR primers for genetic diversity study. The minimum number of SSR primers that could readily be used for identification of the 36 cassava genotypes was also determined. For the genetic diversity study, the similarity coefficients generated between released varieties and central Kerala varieties ranged from 40 to 95% and two separate DNA cluster groups were formed at 0.60 coefficients using “numerical taxonomy” and “multivariate analysis system software package”. The similarity index for released varieties ranged from 60 to 93% and in the case of central Kerala varieties it ranged from 70 to 98%. The mean fixation index (F) for released varieties was 0.0688 and that for central Kerala collections was 0.1337, indicating an overall conformance to Hardy-Weinberg equilibrium. Principal component analysis helped in identifying primers which contributed much to the variation present in the population and reduce the cost and time of research for genetic diversity and genotype identification studies for cassava genetic improvement programs.

Key words: Cassava, genetic diversity, genotypes, microsatellites, principal component analysis, similarity index, simple sequence repeats primers.