IDENTIFICATION OF POLYMORPHIC DNA MARKERS IN CULTIVATED PEANUT (ARACHIS-HYPOGAEA L.)

The detection of DNA polymorphism in cultivated peanut (Arachis hypoga ea L.) is reported here for the first time. The DNA amplification fing erprinting (DAF) and amplified fragment length polymorphism (AFLP) app roaches were tested for their potential to detect genetic variation in peanut. The AFLP approach was more efficient as 43% of the primer com binations detected polymorphic DNA markers in contrast to 3% with the DAF approach. However, the number of polymorphic bands identified usin g primers selected in both approaches was comparable. In the DAF study , when 559 primers of varying types were screened, 17 (mostly 10-mer t ypes) detected polymorphism producing an average of 3.7 polymorphic ba nds per primer with a total of 63 polymorphic markers. In the AFLP stu dy, when 64 primer combinations (three selective nucleotides) correspo nding to restriction enzymes Eco RI and Mse I were screened, 28 detect ed polymorphism. On an average, 6.7% of bands obtained from these 28 p rimer pairs were polymorphic resulting in a total of 111 AFLP markers. Our results demonstrate that both AFLP and DAF approaches can be empl oyed to generate DNA markers in peanut and thus have potential in the marker-assisted genetic improvement and germplasm evaluation of this e conomically important crop.