Deficit irrigation enhances yield and water productivity of apples by inhibiting excessive vegetative growth and improving photosynthetic performance

作者：Shenglin Wen, Ningbo Cui, Yaosheng Wang, Daozhi Gong, Liwen Xing, Zongjun Wu, Yixuan Zhang, Zhihui Wang · 发表于：Agricultural Water Management · 年份：2024 · DOI：10.1016/j.agwat.2024.109220 · 被引用次数：19 · 研究领域：Irrigation Practices and Water Management、Plant Physiology and Cultivation Studies、Greenhouse Technology and Climate Control

Excessive irrigation in orchards can lead to wastage of water resources and instability or reduction in fruit yield. Therefore, this study aims to comprehensively explore the relationships among growth indicators, photosynthetic parameters, apple yield, and water productivity (WP) based on structural equation modeling (SEMD), and develop the appropriate irrigation management strategy for sustainable apple production. A two-year apple irrigation management experiment was carried out with 17 deficit drip irrigation (DDI) treatments, including a control treatment (CK, 100 % ET c ) and 4 water deficit degree (W15 %, 85 % ET c ; W30 %,70 % ET c ; W45 %, 55 % ET c ; W60 %, 40 % ET c ) during four growth stages: bud burst to leafing stage (I), flowering to fruit set stage (II), fruit expansion stage (III), and fruit maturation stage (IV). Results indicated that transpiration rate (T r ) was more sensitive to water deficit than net photosynthesis rate (P n ), leading to greater instantaneous water use efficiency (WUE i ). Compared to the CK, the W15 % DDI treatments at different growth stages slightly reduced P n and significantly decreased T r , thereby enhancing WUE i by 14.5 %-14.9 %. W15 % DDI treatments during the early growth stage restrained excessive growth while enhancing fruit development. SEMD analysis revealed that LAI had a significant positive effect on ET with a standardized path coefficient of 0.312 (P < 0.05) in 2021 and 0.498 (P < 0.001) in 2022, and fruit volume ha...