【摘要】 【目的】探讨水肥耦合效应对‘美味’苹果Malus domestica‘Ambrosia’幼树生长及光合指标的影响，为矮砧密植园栽培幼树的水肥管理提供科学依据。【方法】以阿克苏红旗坡农场新疆农业大学苹果国家良种基地‘美味’苹果幼树为研究对象，灌溉定额分2个水平：W1（3 400 m³/hm²）与W2（2 720 m³/hm²）；施肥量设3个水平：F1（496 kg/hm²）、F2（397 kg/hm²）、F3（298 kg/hm²），对照为CK1和CK2，即分别为W1和W2。试验采用裂区设计，共设8个处理，5次生物学重复，共40个小区。在不同生育期测定树高生长量、叶面积指数、SPAD值、光合指标以及叶绿素荧光参数。【结果】水肥耦合处理下树高生长量和SPAD值由高到低依次为W1F1、W1F2、W1F3、W2F1、W2F2、W2F3、CK1、CK2,W2F1处理的叶面积指数最高，CK1的叶面积指数最小。苹果幼树的树高生长量、叶面积指数、SPAD值变化趋势基本一致，在萌芽开花期、新梢生长期、坐果膨大期快速增加，而成熟期时趋于稳定。W1F1处理相比其他处理对‘美味’苹果幼树光合指标的影响较高。净光合速率（P_n）与胞间CO₂浓度（C_i）在坐果膨大期W1F1处理下达到最高，相比于对照组CK2提高了6.07、50.86μmol/（m²·s）。蒸腾速率（T_r）与气孔导度（G_s）在新梢生长期与对照组之间的差异性达到最高。同生育期各处理间的实际光化学效率Ф_PSⅡ无显著差异。【结论】通过在水肥耦合效应下，测定树高生长量、SPAD值、叶面积指数、光合指标及叶绿素荧光参数，表明W1（3 400 m³/hm²）与F1（496 kg/hm²）的水肥组合更有利于促进新定植的‘美味’苹果幼树树体生长。更多还原

【Abstract】 【Objective】To explore the effect of water-fertilizer coupling effect on the growth and photosynthetic indexes of young trees of Malus domestica ‘Ambrosia’ and to provide scientific basis for the water-fertilizer management of young trees cultivated in dwarf rootstock and dense plantation.【Method】Using young ‘Ambrosia’ apple trees from the Xinjiang Agricultural University Apple National Seed Base at Hongqipo Farm, Aksu, the irrigation quota was divided into two levels: W1（3 400 m³/hm²） and W2（2 720 m³/hm²）; Three levels of fertilizer application were set: F1（496 kg/hm²）, F2（397 kg/hm²）, F3（298 kg/hm²）, and the controls were CK1 and CK2（which was W1 and W2, respectively）. The experiment was conducted in a split-zone design with eight treatments, five biological replications, and a total of 40 plots of experimental trees. Tree height growth, leaf area index, SPAD value, photosynthetic indexes, and chlorophyll fluorescence parameters were measured at different fertility periods.【Result】The tree height growth and SPAD values under water-fertilizer coupling treatments were, in descending order, W1F1, W1F2, W1F3, W2F1, W2F2, W2F3, CK1 and CK2, with the highest leaf area index in the treatment of W2F1 and the smallest leaf area index in CK1. The trends of tree height growth, leaf area index, and SPAD values of young apple trees were basically the same, with a rapid increase during the budding and flowering period, the new shoot growth period, and the fruit-sitting and expansion period, and stabilized at the maturity stage. The W1F1 treatment had a higher effect on the photosynthetic indexes of young ‘Ambrosia’apple trees compared with the other treatments. Net photosynthetic rate（P_n） and intercellular CO₂ concentration（C_i） were highest under the W1F1 treatment during fruit set and expansion, and increased by 6.07 and 50.86 μmol/（m2·s） compared with the control CK2, transpiration rate（T_r） and stomatal conductance（G_s） reached the highest variability with the control at the neoteny stage, and there was no significant difference in the actual photochemical efficiency Ф_PSⅡ between treatments when compared through the different fertility stages.【Conclusion】By measuring tree height growth, SPAD value, leaf area index, photosynthetic indexes and chlorophyll fluorescence parameters under the water-fertilizer coupling effect, it was shown that the water-fertilizer combination of W1(3 400 m³/hm²) and F1（496 kg/hm²） was more conducive to promoting the tree growth of newly planted young ‘Ambrosia’ apple trees.更多还原