COMPARATIVE STUDY OF WHEAT GENOTYPES UNDER OPTIMUM AND WATER DEFICIT CONDITIONS

A set of 14 wheat genotypes including two checks were evaluated under irrigated (non-stress) and rainfed (stress) conditions for yield and yield components during 2009-10 at Khyber Pakhtunkhwa Agricultural University, Peshawar. Analysis across two environments revealed highly significant differences (P ≤ 0.01) between the two production systems for tillers m-2and grain yield, significant differences (P ≤ 0.05) for number of grain spike-1while non significant differences were observed for 1000-grain weight. Similarly, genetic variation among the genotypes was also highly significant for spike length and 1000-grain weight while non significant for the rest of the parameters. Genotype × environment interaction was significant for tillers m-2 and number of grain spike-1 only. Averaged over 14 wheat genotypes, reduction in tillers m-2, spike length, grains spike-1 and grain yield under rainfed environment was 127 m-2, 0.9, 7 and 707 kg ha-1, respectively compared to irrigated environment. For majority of the studied traits heritability was found lower under drought stress conditions compared to non-stressed conditio