Characterization of lablab bean (Lablab purpureus (L.) Sweet) germplasm for agro-morphological and biochemical traits of forage value

Abstract

Lablab bean is one of the important legume crops of tropical and subtropical parts of the world. Its green pods possessed high nutritive value, while green foliage and vines provide hay and silage. Characterization of germplasm is the foremost step for genetic improvement of any crop. In the present study, 135 accessions of lablab bean, along with two checks, were characterized for eight qualitative and eleven quantitative traits, as well as three forage biochemical traits (total chlorophyll, total carotenoids, and total phenolics). Wide variability was observed among the lablab bean genotypes for all the agro-morphological and biochemical traits. In the majority of genotypes, growth habit was spreading, followed by semi-erect and erect. Narrow-leaf shape showed predominance over oval and hastate shapes. The green color of veins was predominant over purple color, while smooth pods were predominant over hairy pods. The leaves, flowers and pods showed wide color variation. The phenotypic coefficient of variance (PCV) was slightly higher than the genotypic coefficient of variance (GCV) for all the quantitative and forage biochemical traits. Traits such as plant height, number of branches, pod length, number of seeds per pod, green forage yield, and total phenols exhibited high estimates of all variability components, including GCV, PCV, broad-sense heritability, and genetic advance over the means. The best genotypes for total carotenoids were ICO411027 and ICO411085 (208.6 μg/g each), while for total phenols were ICO411060 and ICO411127 (29.7 mg/g each). The genotypes characterized here can be utilized to strengthen future lablab breeding programs.