Genetic variability and divergence studies on seed traits and L-dopa content of Mucuna pruriens (L.) DC. accessions

Abstract

Mucuna pruriens (L.) DC. belongs to the Fabaceae family and is widely distributed across the tropical and subtropical regions of the world. Seeds of Mucuna are the industrially important source of natural L-dopa. The present study is intended to screen out the superior Mucuna germplasm which can be utilized for commercial cultivation. A total of 59 accessions of M. pruriens (L.) DC. were collected from various geographical locations across India and evaluated for seed-associated agronomic traits and L- dopa content in the seed. Morphological observations of seed samples revealed a wide variation in seed color pattern including complete white, black and striped/mottled. Quantitative traits such as 100 seed weight (90.30-150.59gm), seed length (5-19.3 mm), width (2.66-13.00 mm), thickness (0.90–8.67 cm), length width ratio (1.17–2.26), length thickness ratio (1.50–7.40), width thickness ratio (0.89-6.00) seed geometric diameter (2.34–12.60 mm), arithmetic mean diameter (2.88–13.33 mm), seed sphericity (41.89–78.75), seed surface area (17.19-498.51 mm2) and L-dopa content (1.79–6.05%) were evaluated in order to compare the features of the accessions collected from different places. The inter-association between morphological observations and L-dopa content was measured using principal component analysis and Ward’s hierarchical clustering, as these are of vital importance in selecting the best accession of velvet bean for breeding programs.