Molecular Characterization of Rice (Oryza sativa L.) Landraces from Southern Karnataka by Using Simple Sequence Repeat (SSR) DNA Markers

摘要

Genetic diversity among rice landraces using simple sequence repeat (SSR) DNA markers was taken up to find the extent of variation. Forty six rice landraces (Oryza sativa L.) were collected from South Karnataka locations for genetic diversity analysisusing seventy four SSR markers distributed on twelve rice chromosomes. Upon PCR amplification the alleles were separated by using MultiNa, a microchip electrophoresis system. A total of 1301 amplicons were generated among the landraces from marker analysis. The number of alleles per locus ranged from 4 to 34 with an average of 18 polymorphic alleles per locus. PIC value varied from 0.59-0.96 with an average of 0.87 per primer. It was found to be highest for the primers RM 2190, RM 6673, RM 7642 and RM1159 while the lowest value was for RM263 marker. The major allele frequency ranged from 0.06 to 0.54 with mean of 0.21 and the average gene diversity was 0.88 with the range between 0.66-0.97. The dendrogram constructed based on SSR markers differentiated 46 landraces, which were distinctly clustered into three main clusters viz., Cluster A, B and C. Three main clusters comprised of 26, 17 and 5 landraces, respectively, that showed a high degree of diversity among the cultivars. The results of the genetic diversity information will be very useful for proper identification, characterization, and conservation of rice landraces and also serves as the sources for parental selection in hybridization.