Genetic distances revealed by RAPD and SSR markers and their relationships with hybrid performance in Asiatic cotton (Gossypium herbaceum and Gossypium arboreum)

Genetic distances revealed by RAPD and SSR markers were used to predict the performance and heterosis of crosses in Asiatic cotton. The experimental material comprised seven genotypes of G. herbaceum L. as female parents and nine genotypes of G. arboretum L. as male parents and their 32 F(1) hybrids. These 32 hybrids and their parents were evaluated for 17 yield attributing and fibre quality characters at Regional Research Station Farm, Anand Agricultural University, Anand. The 16 parents were analyzed with 15 RAPD primers and 10 microsatellite primer sets via polymerase chain reaction (PCR). The RAPD analysis with 15 arbitrary oligonucleotide primers amplified a total of 209 DNA bands out of which 160 were found to be polymorphic. The average polymorphism recorded by the RAPD loci was 74.94%. SSR analysis with 10 microsatellite markers produced 14 alleles. The average number of alleles per locus were found to be 1.40. All 10 microsatellite primer sets representing 14 alleles in the cotton genome showed polymorphisms among the 16 parents. Cluster analysis based on distance calculated from the 25 (15 RAPDs and 10 SSRs) non-redundant variants separated the 16 parental lines into two major groups that corresponded to Gossypium herbaceum and Gossypium arboreum. Associations between the different estimates of GDs and F(1) performance for some traits were significant, but not for many yield and yield attributing as well as fibre quality traits. The genetic distances of parental lines did not appear to be reliable for predicting the heterosis in their hybrids.