Analysis On DNA Polymorphism And Genetic Relationships In Cultivated Peanut (Arachis Hypogaea L) Using Microsatellite Markers

Cultivated peanut (Arachis hypogaea L.) is an important crop for oil and cash worldwide. Despite the existence of substantial diversity among cultivated peanut genotypes for various morphological, physiological and agronomic traits, very little DNA variations had been detected by using RFLPs and RAPDs.Microsatellites or single sequence repeats (SSR) have now been recommended as standard markers because they are highly polymorphic,highly abudant and reliable.In the present study, 11 SSR primer pairs were used to amplify the genomic DNA isolated from 24 peanut genogypes and 4 primers detected polymorphism among the genotypes studied. A total of 33 alleles were detected by 4 SSR loci. The average number of alleles per locus was 8.25, and up to 13 alleles were found at one locus.The genetic similarity (GS) indexes among 24 cultivated peanut accessions are culculated based on the SSR markers. The value of GS varies from 0.2 to 1.0.with an average of 0.4788.The results of UPGMA indicated that the 24 accessions could be divided into two types at 0.463 , and each type could be devided into two groups at 0.044 and 0.060 respectively.Peanut genotypes sorted by SSR markers are similarto the results observed by agronomic traits,with 79.2% similarity rate at two types and 62.5% at 4 groups respectively.The results showed that microsatellite is one of the best DNA markers to analyze DNA polimorphism and genetic relationship in cultivated peanut.