Physiological response of wheat (Triticum durum L.) to limited irrigation

A field study was conducted at CCS Haryana Agricultural University, Hisar, during two consecutive rabi seasons of 2002-03 and 2003-04 on wheat genotypes. The main plots treatment consisted of three irrigation schedules viz., normal irrigation (Control), two irrigations at 45 and 85 DAS (limited irrigation) and no post sowing irrigation (rainfed) and in sub-plots five genotypes were grown namely WH 896, WH 912, WHD 935, WHD 936, PDW 233, Raj 1555. The restricted irrigation decreased the leaf water potential (LWP), canopy temperature depression (CTD), transpiration rate, stomatal conductance and photosynthesis significantly over irrigated control, while, significant increase was observed in plant water retention. Reduction in grain yield under rainfed condition was 23.4 per cent. Reduced irrigation application decreased the yield attributes with maximum reduction in number of grains per spike. Genotype PDW 233 yielded significantly higher than all other tested genotypes. It maintained higher plant water status and higher rate of photosynthesis than other genotypes.