Effect of moisture stress on plant water relations and yield of different wheat genotypes

A field experiment was conducted to study the effect of moisture stress on wheat genotypes grown under irrigated, mild stress and severe stress conditions. Canopy temperature depression (CTD), relative water content (RWC) and water potential (Ψ_w) decreased significantly with increase in moisture stress. The CTD was higher in genotypes IWP 72, PBW 175 and C 306 both in mild as well as severe moisture stress by keeping their canopy cooler. Maximum RWC was found in PBW 175 followed by IWP 72 and PBW 343. Moreover, these genotypes exhibited higher water potential. Yield and its attributes for all genotypes decreased significantly in the stressed environments. The per cent reduction in grain yield over control was 23.8 and 57.6 in mild and severely stressed treatments respectively. Maximum reduction in yield (66.8%) under severe stress was observed in genotype PDW 233. However, genotype C 306 exhibited least reduction in yield i.e. 7.8% and 39.7% under mild and severe stress, respectively. It can threfore, be concluded that the high yielding genotypes should maintain cooler canopy, higher internal water status and yield attributing characters under the depleting soil moisture condition.