1Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore-641 003, Tamil Nadu
2Department of Oilseeds, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore-641 003, Tamil Nadu
*Author for Correspondence: E-mail: soundhini@yahoo.co.in
Online published on 12 August, 2013.
The best characterized form of drought tolerance in sorghum during crop growth is the non-senescence or “stay-green” trait. To assess the genetic diversity available in sorghum germplasm for drought tolerance, 16 stay-green specific simple sequence repeat markers (SSR) were used of which 10 were polymorphic. A total of 47 scorable alleles were generated by these 10 primers of which 44 were polymorphic (93.6%). The number of alleles produced by different primers ranged from three to seven with an average of 4.7 alleles per primer. Similarity coefficients based on 10 polymorphic SSR markers ranged from 0.205 to 0.864. The dendrogram grouped the sorghum accessions into 11 major clusters and categorized the drought-resistant and drought-susceptible genotypes into separate clusters. Most of the genotypes in the cluster I and IV had better stay-green score ranging between 1.80 to 2.5. The study revealed that the presence of genetic diversity is high among the accessions and the staygreen specific primers sorted the genotypes based on their level of drought tolerance.
Cluster, Drought tolerance, Polymorphism, Simple sequence repeats, Stay-green
