EFFECT OF SOIL MOISTURE DEPLETIONS AND DE-TOPPING ON YIELD AND YIELD COMPONENTS OF CHICKPEA

Irrigation at four available soil moisture depletion levels i.e. ASMDL1 (50%), ASMDL2 (65%), ASMDL3 (80%), ASMDL4 (95%) and three de-topping treatments with control i.e. T1 (topping at 5 cm height from ground level), T2 (topping at 10 cm height from ground level), T3 (removal of 2 cm growing tips) and T4 (control) were studied in split plot arrangements. Main plot consisted of four available soil moisture depletion levels (ASMDL) whereas de-topping treatments were kept in sub-plots. The experiment was laid out at Arid Zone Research Institute Bhakkar during Rabi (winter) of 2004-05 and 2005-06 with the objectives to determine optimum soil moisture requirements for higher yield and to assess the effect of de-topping on yield and yield components of chickpea. Irrigation was started 50 days after sowing (DAS) while de-topping treatments were applied 70 DAS. Yield and yield components were significantly affected by ASMDL and topping treatments. Maximum number of pods plant-1 (45.09) were recorded in ASMDL3 and decreased 19 % in ASMDL4. Two years’ average number of seeds pod^-1, 100 seed weight, biological yield (kg ha^-1), seed yield (kg ha^-1) and harvest index (%) ranged from 1.71 to 1.87, 26.34 to 28.14, 5219 to 6883, 2102 to 2986 and 38.95 to 42.76 in ASMDL whereas their averages in de-topping treatments ranged from 1.77 to 1.89, 26.41 to 28.29, 5304 to 6924, 2269 to 2999 and 37.18 to 42.90. ASMDL4 (95 % depletion) decreased 24 and 30 % total dry biomass and grain yield and maximum water use efficiency, 19.60 kg ha^-1 mm^-1 for seed yield was recorded in ASMDL3. Biological and seed yields were decreased 23 and 24 %, respectively by T1. It was concluded that supply of irrigation at 80 % available soil moisture depletion level (ASMDL3) in soil with removal of 2 cm growing tips (T3) proved to be the best for higher yield and yield components in chickpea.