Genetic diversity evaluation of some G. arboreum (diploid cotton) varieties by RAPD analysis

Random Amplified Polymorphic DNA (RAPD) analysis was used to evaluate genetic diversity among commercial Indian cotton varieties. Fifteen varieties belonging to Gossypium arboreum were analyzed with 30 random decamer primers using the polymerase chain reaction (PCR). All the primers studied detected polymorphism in all 15 cotton varieties. A total of 384 bands were amplified, 80.2% of which were polymorphic. The most informative primers were OPM-18 and OPM-19 with 15 polymorphic bands and least informative were OPN-02 with only 5 polymorphic bands. The variety RG-8 produced the maximum number of DNA amplified fragment (228), while LD-327 produced 156 bands, which is the minimum number. The value of similarity coefficient ranges from 0.57–0.85. Maximum similarity was observed between DS-1 and DS-2 (0.85). Interestingly, these varieties have been developed at one breeding center. Cluster analysis by UPGMA showed that intervarietal genetic relationships of several varieties are related to their pedigree. The results also show a narrow genetic base among the varieties. The results obtained can be used in selecting divergent parents for breeding and mapping purposes.