Longevity and vigour of pigeon pea (Cajanus cajan (L.) Millsp.) seed stored under humid tropical ambient conditions

Abstract

Seeds of 20 pigeon pea (<em>Cajanus cajan </em>(L.) Millsp.) genotypes were evaluated for seed longevity and vigour under humid ambient conditions. Cleaned seeds of each genotype were packed into a polyethylene bag, the packaged lot was electrically sealed and thereafter placed in a seed store under ambient conditions (30 ºC, RH 75 %). Seed samples were withdrawn at 0, 60, 120, 180 and 240 days after storage for seed quality parameters evaluation. The experiment consisted of two factors which were genotype and storage duration and was a laid out in a completely randomized design with three replications. Data were collected on rate of seed germination, seed viability, seedling length, seedlings fresh mass, seedlings dry mass and seedling vigour index. Data collected were subjected to analysis of variance and significant treatment means were separated using Tukey’s HSD test at 5 % probability level. PROBIT modelling was also used to predict the seed longevity of stored pigeon pea. Significant differences were observed in all seed quality attributes evaluated among the 20 pigeon pea genotypes and storage time except seedling fresh mass. Seed quality attributes decreased significantly with increasing storage periods. Genotypes NSWCC-18A, NSWCC-24, NSWC-34 and NSWCC-29A were identified to be superior for most of the seed quality attributes evaluated. PROBIT modelling result revealed that genotype NSWCC-29b had the highest storage life (16.28 months) and the highest storage potentials in terms of seed viability and other seed quality attributes of all seed lots.