Simple sequence repeat markers for botanical varieties of cultivated peanut (Arachis hypogaea L.)

Cultivated peanut (Arachis hypogaea L.) consists of six botanical varieties. Identification of DNA markers associated with botanical varieties would be useful in plant genotyping, germplasm management, and evolutionary studies. We have developed 130 simple sequence repeat (SSR) markers in peanut, 38 of which were used in this study because of their ability in detecting genetic polymorphism among 24 peanut accessions. Eight SSR markers were found useful to classify botanical varieties. Among them, six SSR markers were specific to botanical varieties fastigiata and vulgaris, one to botanical varieties hypogaea and hirsuta, and one to botanical varieties peruviana, and aequatoriana. Also, three of them derived from peanut expressed sequence tags (ESTs) were associated with putative genes. As botanical varieties have different morphological traits and belong to different subspecies in A. hypogaea, these markers might be associated with genes involved in the expression of morphological traits. The results also suggested that SSRs (also called microsatellites) might play a role in shaping evolution of cultivated peanut. Multiplex PCR of botanical variety-specific markers could be applied to facilitate efficient genotyping of the peanut lines.