灌溉排水学报2026，Vol.45Issue(7)：70-82,13.DOI:10.13522/j.cnki.ggps.2026038
元江干热河谷区微喷灌水钾调控对柑橘光合特性影响研究
Effects of water-potassium regulation under micro-sprinkler irrigation on citrus photosynthesis during fruit development stages in the Yuanjiang dry-hot valley
摘要
Abstract
[Objective]Citrus is a major cash crop in the dry-hot valley of the Yuanjiang Basin,and rational water and potassium management is critical for its fruit quality.This paper presents an experimental study on the effects of water-potassium regulation under micro-sprinkler irrigation on citrus photosynthesis at the fruit swelling and maturity stages,as well as the underlying regulatory mechanisms.[Method]The experiment was conducted in an orchard of 12-year-old Bingtangcheng citrus trees from the fruit swelling and maturity stages.Sufficient irrigation combined with local standard potassium application rate served as the control(CK).There were three deficit irrigation treatments:mild water deficit(LD),moderate water deficit(MD)and severe water deficit(SD),with irrigation amount being 85%,70%and 55%of that in the CK,respectively;and two potassium fertilization treatments:applying 85%(MK)and 70%(LK)of that in the CK.During the experiment,we measured the diurnal dynamics of leaf photosynthetic parameters before and after each re-watering.Structural equation modeling was used to identify the physiological pathways through which water-potassium interaction regulates citrus photosynthesis.[Result]① After rewatering at both growth stages,the daily mean net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance(Gs),carboxylation efficiency(CE)and instantaneous water use efficiency(WUEi)increased significantly after rewatering due to alleviation of water deficit(p＜0.001),whereas intercellular CO2 concentration(Ci)declined markedly(p＜0.001).The LD treatment was optimal for photosynthesis.②The effect of potassium application on photosynthesis varied with growing stages.MK significantly increased Pn at the swelling stage but inhibited it at the maturity stage(p＜0.001).③Stomatal behavior regulated by irrigation amount was the key limiting factor affecting photosynthesis at both the fruit swelling and maturity stages.At the fruit swelling stage,increasing potassium application increased leaf potassium content,synergistically promoting stomatal and non-stomatal processes and ultimately improving photosynthesis.At the maturity stage,increasing potassium application aggravated non-stomatal limitation,thereby inhibiting photosynthesis.[Conclusion]A combination of moderate potassium application and mild deficit irrigation(MK+LD)is optimal at the swelling stage,while mild potassium application combined with mild deficit irrigation(LK+LD)works better at the maturity stage.These irrigation and fertilization strategies improves citrus production in the study region.关键词
柑橘/微喷灌/水钾一体化/光合日变化Key words
citrus/micro-sprinkler irrigation/integrated water-potassium management/diurnal variation of photosynthesis分类
农业科技引用本文复制引用
李伟康,赵璐,朱国宇,吴明清,谭明东,崔宁博,高志永,邢立文,温圣林,姜守政,王智慧..元江干热河谷区微喷灌水钾调控对柑橘光合特性影响研究[J].灌溉排水学报,2026,45(7):70-82,13.基金项目
国家重点研发计划项目(2023YFD1901203) （2023YFD1901203）
国家自然科学基金项目(52279041,52309055) （52279041,52309055）
四川省科技计划项目(2024ZHCG0101,2023YFN0024,2024YFHZ0200,2024YFHZ0217,2026YFHZ0094) （2024ZHCG0101,2023YFN0024,2024YFHZ0200,2024YFHZ0217,2026YFHZ0094）
云南省农业基础研究联合专项面上项目(202301BD070001-181) （202301BD070001-181）
中央高校基本科研业务费项目(20822041J4119) （20822041J4119）
云南省教育厅科研基金项目(2024Y305) （2024Y305）
