枸杞苜蓿间作模式下水分调控对枸杞光合特性与水分利用的影响

针对中国西北干旱半干旱地区枸杞种植模式单一、水分利用低下的农业生产现状,探究更为有效的田间管理措施以提高枸杞产量,并实现水土资源高效利用。基于大田试验,对比分析了2种种植模式(枸杞单作CK和枸杞‖苜蓿LA)与4种水分条件(充分灌水W0(75%～85%)、轻度亏水W1(65%～75%)、中度亏水W2(55%～65%)和重度亏水W3(45%～55%))对枸杞耗水特征、光合特性、生长量、产量和水分利用效率的影响。结果表明:(1)枸杞‖苜蓿(891～1 243 mm)的生育期耗水量高于枸杞单作(829～1 102 mm),且均随灌水亏缺程度的提高呈降低趋势。(2)枸杞单作模式下,净光合速率和蒸腾速率的双峰趋势较枸杞‖苜蓿模式明显;同一种植模式下,随着水分亏缺程度的加剧,枸杞叶片净光合速率和蒸腾速率的峰值有所降低且峰值出现的时间有所提前。(3)同一种植模式下,随着水分亏缺程度的增加,枸杞地径、株高、冠幅和新梢的生长量均呈降低趋势,但降低幅度趋于减小;单作模式下,处理CKW1具有较高的产量(3 720 kg/hm~2)和水分利用效率(3.61 kg/(hm~2·mm));间作模式下,处理LAW0具有较高的产量(3 780 kg/hm~2)和水分利用效率(3.08 kg/(hm~2·mm))。综合得出,枸杞单作模式下,一定程度的水分亏缺有助于提高枸杞产量和水分利用,而枸杞‖苜蓿模式下,应保证充足的土壤水分供应以获得较高的枸杞产量和水分利用。

Effects of Water Regulation on Photosynthetic Characteristics and Water Use of Lycium Barbarum Under the Mode of Intercropping Alfalfa and Lycium Barbarum

In the arid and semi-arid regions of northwestern China, Lycium barbarum production is facing the problems of single planting pattern and low water use efficiency. The purpose of this study was to explore more effective field management measures to increase L. barbarum production and achieve efficient utilization of land and water resources. Based on field experiments, the effects of two planting patterns and four water conditions on water consumption characteristics, photosynthetic characteristics, growth, yield, and water use efficiency of L. barbarum were compared and analyzed. The two planting patterns were L. barbarum monoculture (CK) and intercropping of L. barbarum and Alfalfa (LA). The four kinds of water condition were full irrigation (W0, 75%~85%), mild water deficit (W1, 65%~75%), moderate water deficit (W2, 55%~65%), and severe water deficit (W3, 45%~55%). The results showed that:(1) The water consumption during the growth period of LA (891~1 243 mm) was higher than that of CK (829~1 102 mm), and decreased with the increasing of water deficit. (2) In CK, the double peak trends of net photosynthetic rate and transpiration rate were more obvious than those of LA. Additionally, under the same planting mode, the peaks of net photosynthetic rate and transpiration rate of L. barbarum leaves decreased and the peaks appeared earlier with the aggravation of water deficit. (3) Under the same planting mode, the growth amount of L. barbarum ground diameter, plant height, crown width and new shoots decreased with the aggravation of water deficit, but the decreasing range tended to decrease. In the single planting mode, the treatment of CKW1 had higher yield (3 720 kg/hm²) and water use efficiency (3.61 kg/(hm²·mm)). In the intercropping mode, the treatment of LAW0 had higher yield (3 780 kg/hm²) and water use efficiency (3.08 kg/(hm²·mm)). In conclusion, a certain degree of water deficit was helpful to improve the yield and water use efficiency of L. barbarum in the single planting mode, and sufficient soil water supply should be ensured to obtain higher L. barbarum yield and water use efficiency in the intercropping mode.