SEASONAL GROWTH ATTRIBUTES OF WHEAT (Triticum aestivum L.) GENOTYPES IN RESPONSE TO MOISTURE REGIMES UNDER SEMI ARID ENVIRONMENT

A field experiment for the comparison among different wheat genotypes (iqbal-2000, chenab-2000, aqab-2000) for its maximum yield potential in response to different moisture regimes, a randomized complete block design (rcbd) with split plot arrangement in triplicate run was carried out during the year 2006-07. factors were: wheat genotypes (iqbal-2000, chenab-2000, aqab-2000) in main plots and five irrigation levels i0= no irrigation (control), i1= irrigation at tillering, i2= irrigation at tillering + booting, i3= irrigation at tillering + booting + anthesis and i4= irrigation at tillering + booting + anthesis + milking in subplots. results showed that maximum lai was attained on 2 february and 4 march harvest and genotype iqbal-2000 was superior compared to other genotypes. irrigated treatments significantly increased lai than control (i0) treatments at all harvest dates. iqbal-2000 showed maximum cgr (32.69 g m^-2 d^-1) and lad (319.42) compared with lowest cgr (25.49 g m^-2 d^-1) and lad (278.50) given by genotype chenab-2000 under i3 and i4 treatments throughout the growing season. radiation use efficiency ranged from 17.58-18.27 dm mj^-1 of intercepted radiation. mean accumulated radiation interception (754, 736 and 784 mjm^-2) was assessed in genotypes (iqbal-2000, chenab-2000 and aqab-2000), respectively but not significant effect on net assimilation rate. genotype iqbal-2000 and aqab-2000 had highest tdm (21670; 21220 kg ha^-1) respectively while i4 (irrigation at tillering + booting + anthesis + milking) had the highest tdm 22240 kg ha^-1 verses i0 (no irrigation) 18070 kg ha^-1. aqab-2000 showed the highest grain yield (5458.78 kg ha^-1) as compared to chenab-2000 (4536.71 kg ha^-1) whereas i4 (irrigation at tillering + booting + anthesis + milking) produced more grain yield (6376.25 kg ha^-1) than all other irrigation treatments.