The effect of water use optimizing on yield of two wheat cultivars in sole cropping and intercropping systems

The effect of water use optimizing on yield، yield components، harvest index and biomass of two wheat cultivars (Zarrin and Gaspard) in intercropping and sole cropping systems was evaluated in research farm of agriculture faculty of Zanjan university، Iran during 2010-2011. Experiment was carried out as split block based on a randomized complete block design with three replications. Factors were planting pattern at three levels of 100% Zarrin، 50% Zarrin+50% Gaspard، and 100% Gaspard and irrigation at four levels of full irrigation in all growth stages (control)، irrigation interrupt at shooting stage of wheat، irrigation interrupt at grain milky stage، and irrigation interrupt at grain hardening crummy stage. Results showed that irrigation had a significant effect on grain yield، biomass، harvest index، the average number of grains per spike and 1000 grain weight. The interaction effect of the factors and planting pattern levels on grain yield، biomass، harvest index، the average number of grains per spike was also significant. The highest grain yield (7905 kg. ha-1) was obtained from control in intercropping of Gaspard and Zarrin that was 2. 14 and 24. 98 percent higher than that of Gaspard and Zarrin sole cropping، respectively. Land equivalent ratio index (LER) was more than one at treatments of irrigation interrupt at grain hardening (1. 26) and control (1. 1) in intercropping and showed that Gaspard and Zarrin intercropping was better than sole cropping system. Results also revealed the possiblity of reducing once irrigation in grain hardening crummy stage for Zarrin and Gaspard varieties production.