IDENTIFICATION OF DNA POLYMORPHISM IN CULTIVATED GROUNDNUT (Arachis Hypogaea L.)

Abstract

Initial studies in the germplasm of cultivated groundnut using RFLP and RAPD revealed very limited polymorphism (Kochert et al., 1991, Halward et al., 1992) and led to the opinion that cultivated groundnut has a very narrow genetic base. However, the studies by He and Prakash (1997) indicated the possibility of exploiting DAF and AFLP techniques for the detection of polymorphism in groundnut. In the present study, Amplified Fragment Length Polymorphism (AFLP) was done using 64 combinations of primers specific to EcoRI and Mse I with the selective nucleotides in 12 groundnut cultivars. Primer combinations were ranked based on their ability to amplify different fragments, and having more than 10% polymorphism and selected five primer pairs. These primer pairs were further tested in four genotypes viz. TMV 7, Chandra, RS 1 and UF 70-103 for confirmation. All the selected primers could give amplification of the fragments and the banding pattern showed polymorphism. The five primers when tested with cultivars which are selections from Robut 33-1, also shown polymorphism.It could be concluded that the five primers selected were suitable for detecting polymorphism and can be further used in varietal identification and finger printing, and to tag genes of economic importance in breeding programmes.