Genetic variability analysis in elite black pepper genotypes using morpho-physiological and yield-attributing traits

Abstract

The genetic variability in selected 21 black pepper accessions was analyzed based on desirable drought-tolerant and susceptible characteristics using principal component and cluster analyses. The experiment was conducted at ICAR-Indian Institute of Spices Research, Experimental farm, Peruvannamuzhi, Kozhikode using a randomized block design with four replications. Morphological, physiological and yield contributing traits were studied. The traits examined showed a comprehensive range of variability. The principal component and UPGMA clustering analyses were employed to assess the proportional contribution of various traits and grouped the genotypes, respectively. The first principal component was responsible for the highest variation (30.87%) in the yield-related characteristics, which were positively correlated with each other and correlated negatively with the morphological characteristics and stomatal frequency. Separate clusters were formed for the genotypes that displayed drought-tolerant characteristics (cluster 2 and 3) and those that showed susceptible characteristics (cluster 1). The results indicated that the analysed black pepper genotypes have significant genetic variability among them which may be helpful for identification of genotypes with desirable drought tolerant characteristics. Accessions 7211 (cluster 2), 1495, 1343 and 4132 (cluster 3) showed characteristics that make them potentially drought tolerant while the accessions 5717 and 4064 (cluster 1) showed drought susceptible traits.