Abstract:This study was conducted to evaluate the effects of different alternative irrigating-cycle on plant growth, yield and quality and water use efficiency of 11 and 12-year-old apple trees (Malus pumila Mill. cv. Hongjingfu) subjected to control and alternative partial root-zone irrigation (APRI) in Yantai Fruit Research Academy of Agricultural Science from 2006 to 2007. The results showed that in APRI treatments, the soil moisture content in the wet side of apple trees decreased with increasing soil depth, and obviously the alternate shorter period, inflexion point more near the surface, while that in the dry side was adverse, with the maximum difference occurring in 0-10 cm of soil surface layer. For APRI1 treatment (irrigation with 50% of the control, on one side of the root system and switched every 2 weeks), the water potential of leaves, net photosynthetic rate, transpiration rate and stomatal conductance were slightly low, but no significant differences existed compared to CK (irrigated with 100% on both sides of the root system). The above-mentioned indices for both APRI2 (irrigation with 50% of the control, on one side of the root system and switched every 2 weeks) and APRI3 (irrigation with 100% of the control, on one side of the root system and switched every four weeks) were significantly lower than those in the control (P < 0.05). The APRI treatments significantly inhibited the shoot growth of apple trees, but had no significant influence on fruit diameter. Apple yield was significantly higher in both of the control and APRI3 treatments, compared to APRI1 and APRI2 treatments. The slight APRI-induced yield reduction (11.1%-14.8%) compared to the control was achieved by 50% decrease in the total amount of water applied, which resulted in the water use efficiency increase by 71%-80% under APRI1 and APRI2 treatments, compared to the control and APRI3. Furthermore, the APRI1 and APRI2 treatments induced the significant increase of the soluble solids content, dry matter content and fruit hardness, and the decrease of fruit acid content, which made the fruit quality improved obviously. It was concluded that APRI1 had the potential for use in apple orchard as a high-quality efficient irrigation pattern in the arid land.