Assessment of genetic diversity in germplasm of Guinea grass (Panicum maximum Jacq.)

Mucuna pruriens is a nutritionally and pharmaceutically important underutilized legume belonging to genus Mucuna of Leguminosae family. Extensive intraspecific diversity and adverse morphological features among the members have led to taxonomical confusions in the species. A total of 12 Mucuna pruriens accessions including its two botanical varieties, var. pruriens and var. utilis with six accessions each were analyzed to characterize the intraspecific diversity among them using the three barcode markers viz. ITS2, matK and trnHpsbA. Extensive intraspecific sequence diversity was observed in the trnHpsbA region, where as ITS2 and matK exhibited significant conserved regions. Such intraspecific sequence diversity is a limitation in adapting trnHpsbA as barcode as it may lead to misinterpretations, but in the present study an attempt has been made to extrapolate this diversity to explain within the species variations among Mucuna pruriens genotypes. Intraspecific sequence variations exhibited by trnHpsbA sequences were 83% in correlation with morphological features. The between groups mean distance of var. pruriens and var. utilis was found to be 0.346. Results of this study will complement with the existing molecular, morphological, ytological and biochemical markers towards Velvet bean improvement programs.