Water Management of Sunflower Crop Under Liquid Ammonia Gas Fertilization

Abstract

The present investigation was carried out at Tamiea Agric. Res. Station, Fayoum Governorate during 2009 and 2010 seasons to study the effects ofammonia fertilizer levels, i.e. N 1 : 15, N 2 :30 and N 3 :45 and N 4 : 60 kg N fed -1 ,four irrigation regime i.e. irrigation at I 1 : 0.6, I 2 : 0.8, I 3 : 1.0 and I 4 : 1.2cumulative pan evaporation (C.P.E.) and their interaction on yield, yield components and some crop water relations of sunflower (Sakha 53). The strip-plot design with four replicates was used. The obtained results were as follow:Yield and all yield components i.e. plant height, head diameter and weight, as well as seed weight head -1 and 100-seed weight, were obtained from applying 60 kg N fed -1 and irrigating sunflower at 1.2 C.P.E., surpassed significantly those obtained from the other treatments. However, the highest seed oil content were detected fromapplying 15 kg N fed -1 and irrigating sunflower at 1.2C.P.E.Seasonal water evapotranspiration (ET C ) reached its maximum values (54.69 and 53.05 cm in 2009 and 2010 seasons, respectively), as sunflower crop received60 kg N fed -1 and irrigated at 1.2C.P.E.. The daily ETc increased by increasing the irrigationintervals from 0.6 to 0.8 to 1.0 to1.2 C.P.E.. The peak of daily ETc occurred on July. The K C (crop coefficient) during the growing seasons were 0.42, 0.52, 0.62,0.88 and 0.51 for May, June, July, August and September months, respectively, (means of two seasons).Applying 60 kg N fed -1 and irrigation at 1.2C.P.E. gave the highest water use efficiency, i.e. 0.497 and 0.480 kg seeds m -3 water consumed in 2009 and 2010 seasons, respectively.