Effect of complementary irrigarion during reproductive growth period on grain yield, oil and energy efficiency of rapeseed under dry land farming system

Effect of complementary irrigation during reproductive growth stage on grain yield, percent and yield of oil and energy efficiency of rapeseed was evaluated in a dry land farming system. Experiment was conducted with three treatments (without complementary irrigation, one complementary irrigation during flowering and two complementary irrigations during flowering and grain filling periods) and three replications. Results indicated that silique number, grain number per silique, 1000-grain weight, biological yield, harvest index, percent and yield of oil were significantly (P≤0.01) improved by complementary irrigation. One and two complementary irrigation improved grain yield by 56 and 91 percent, respectively. Oil percent increased by one and two complementary irrigation from 32.18 to 35.0 and 37.22 percent, suggesting the improvement of oil yield up to 43 and 75 percent, respectively. Total energy input of barley dry land farming was 29007 MJ.ha-1, where the height input energy was belong to fertilizer. Supplemental irrigations increased input energy of the system. However, 488 and 789 kg/ha increasing in grain yield of one and two complementary irrigations resulted in 10596 (56 percent) and 17121 (91 percent) MJ.ha-1 of energy output of the system, respectively, suggesting supplemental irrigation can improve energy efficiency of rapeseed dry land farming system.