Effect of boron on the yield of wheat (Triticum aestivum L.) under center pivot sprinkler irrigation system in the West Desert of Iraq
Two field experiments were conducted under field conditions under a sprinkler irrigation system in the West desert of Iraq, Al-Qaim Area, 400 km west of Baghdad. Underground water was used as a source of irrigation water to study the effect of different rates and different times of boron application on wheat cv. Ibaa99. RCBD with five treatments and three replications was used in this study. Boron dose was 2 kg/ha for soil application method and 0.30 kg/ha for foliar application method. Boron treatments were: 0 (control T1), 2 kg B ha-1 at sowing time (T2), 2 kg B ha-1 at 30 days after sowing (T3), 0.3 kg B ha-1 foliar application at 60 days after sowing (T4) and 0.3 kg B ha-1 for foliar application at 90 days after sowing (T5). Most boron treatments gave a significant increase as compared with control in morphological, physiological and productivity characters of wheat crop. The results revealed that B application treatment at 30 days after sowing time increased significantly the 1000 grains weight (17.6%) while T5 treatment increased significantly the chlorophyll content (12.41%) over control. In most cases, B application treatment at 60 days after sowing time showed the best results and increased significantly the plant height (5.24%), leaf area (9.18%), number of grains spike-1 (30.9 %), number of spike m-2 (18.8%), spike length (65.6%), Grains yield (34.6%) over control. There was evidence that the best dose of boron was 0.3 kg B ha-1 and the best time of B application to the foliage was at 60 days after sowing.