| To investigate the water-saving irrigation scheduling for full bearing apple trees during different hydrological years in Weibei dryland gully, based on water balance principle, meteorological data from recent 56 years in Luochuan were used to analyze both sufficient and non-sufficient irrigation scheduling of two maturity apple varieties (Gala and Fuji) under different irrigation methods (pipe irrigation and drip irrigation). The results showed that both mid- and late-maturing varieties should be irrigated in different hydrological years. The irrigation stage and amount should mainly be implemented at new shoot growing and fruit expanding stages. In addition, for mid-maturing variety in different hydrological years (wet, normal, dry and extremely dry years) under sufficient irrigation scheduling, irrigation times were 2, 3, 3 and 4, respectively, irrigation quota for drip irrigation were 60, 85, 120 mm and 165 mm, respectively, pipe irrigations were 90,130,180 and 245 mm, respectively; irrigation times under non-sufficient irrigation scheduling were 1, 2, 3 and 4, respectively, irrigation quota for drip irrigation were 45, 70, 110 and 150 mm, respectively, and pipe irrigation were 65, 110, 170 and 220 mm, respectively. Furthermore, for late-maturing variety in different hydrological years under sufficient irrigation scheduling, irrigation times were 2, 3, 4 and 4, respectively, irrigation quota for drip irrigation were 65, 90, 125 and 160 mm, respectively, pipe irrigation were 95, 140, 195 and 240 mm, respectively; irrigation times under non-sufficient irrigation scheduling were 2, 3, 3 and 4, respectively, irrigation quota for drip irrigation were 55, 75, 120 mm and 150 mm, and pipe irrigation were 85, 125, 175 mm and 220 mm, respectively. |