Evaluation of Traits Related to Drought Stress in Sesame (Sesamum Indicum L.) Genotypes

Abstract

In order to evaluate traits related to drought stress in eight sesame (sesamum indicum L.) genotypes, two experiments were carried out in randomized complete design with three replications in the field The two experiments differed with respect to their irrigation regimes. Yield related traits (number of days to maturation, NDM; number of capsules per plant, NCP; 1000 seed weight, TSW; harvest index, HI; biological yield, BY and grain yield, GY) and physiological traits(canopy temperature, T C , leaf water potential, LWP; leaf osmotic potential, LOP; initial water content, IWC and rate of water loss, RWL) were evaluated under both conditions. The results showed that drought decreased all yield related traits except HI, significantly. LWP and LOP decreased under drought stress, while RWL increased, significantly. T C and IWC did not show significant changes under drought stress. Based on the results, it is reasonable to assume that high yield of sesame plants under drought conditions could be obtained by selecting breeding materials with lowest reduction in NDM, NCP, TSW, BY, GY, LWP and LOP and the highest reduction in RWL. Under non-stress condition LOP in both stages was the best traits. Under drought condition LWP, LOP at both stages and RWL at grain filling stage were the most suitable traits. This study is one of very few studies which have investigated the effects of drought stress on physiological and yield related traits of sesame genotypes.