Effects of Water and Fertilizer Coupling on the Yield and Quality of Drip Irrigated Chinese Jujube in an Extreme Arid Region

摘要

In this study, a 2-factor and 5-level quadratic orthogonal rotated composite experimental design was employed to investigate the effects of water and fertilizer coupling on the yield and quality of drip irrigated Chinese jujube in an extreme arid region. The results showed that both water and fertilizer had significant important influences on the yield and quality of drip irrigated jujube and that reasonable and effective fertigation could bring high yield and good quality. Insufficient water would affect nutrient uptake of Chinese jujube and result in the decrease of yield. Similarly, inadequate nutrients would lead to maldevelopment of jujube and finally decrease the yield. When irrigation was at a relatively low level, reasonably increasing fertilizer application could improve the biological trails of jujube, while over-fertilization would inhibit jujube growth and decrease the yield when irrigation was at a relatively high level. Under the experimental conditions, when yield was the pursued economic goal, the suitable water and fertilizer coupling was determined as irrigation amount of 7800 m3/hm2, urea of 456.45 kg/hm2 and potassium dihydrogen phosphate of 755.4 kg/hm2.; when quality was the pursued economic goal, the recommended water and fertilizer coupling was irrigation amount of 7800 m3/hm2, urea of 652.2 kg/hm2 and potassium dihydrogen phosphate of 1079.25 kg/hm2.