| Abstract:Taking the 'Wen 185' walnut treein Aksu area of Xinjiang as test material,two levels of mild (75% ETC) and moderate (50% ETC) were setat the budding stage (Ⅰ),the flowering and fruit-setting stage (Ⅱ), respectively,with combination of stage Ⅰ + stage Ⅱ mild deficit treatment and full irrigation (ETC) in whole growth period as control, the effects of regulated deficit irrigation on walnut tree growth, water consumption, yield and water use efficiency (WUE) under drip irrigation were explored under total six treatments.The results showed that rehydration of walnut trees at the next stage increased the SPAD value of walnut leaves and fruit volume after regulated deficit irrigation.The water consumption of walnut trees during each growth period was in order of oil conversion period (Ⅴ), hard-core period (IV), fruit expansion period (Ⅲ), period Ⅱ, mature period (Ⅵ), and period Ⅰ .The water consumption at stage V accounted for 38.5%-40.37% in whole growth period, which was higher than that in other growth periods.During the water deficit period, water consumption and water consumption intensity was significantly reduced.The effects of water deficit on single fruit mass and kernel quality at stage Ⅰ and stage Ⅱ of single growth period were not significant, but consecutively mild water deficit at stage Ⅰ + stage Ⅱ increased significantly.The yield, WUE and IWUE of walnut trees treated with mild water deficit at the second stage reached a relatively high level.Comprehensive evaluation by the CRITIC method showed that the two results were consistent.Therefore, the optimal adjustment model in this study is a mild adjustment in phase Ⅱ. |
