Investigating morpho-physiological traits and agro-meteorological indices in green gram [Vigna radiata (L.) Wilczek] for terminal heat tolerance

Forty genotypes of greengram were studied to ascertain the genetic variability and trait association among some important morpho-physiological traits and agro-meterological indices under heat stress condition. The results indicated that both GCV and PCV estimates were high for photo thermal index, heat use efficiency and seed yield. High heritability coupled with moderate genetic advance as per cent of mean was recorded for photo-thermal unit and relative temperature depression indicated that involvement of both additive and non-additive type of gene action and possibilities of effective selection for improvement of these traits. Seed yield showed significant and positive association with days to maturity, growing degree days, relative temperature depression and heat use efficiency. Based on variability, association and path analysis; heat use efficiency, maturity, photo thermal index and growing degree days were found most contributing indices/traits should be considered as selection criteria for discrimination of outstanding greengram genotypes under heat stress condition.