为探索间伐改形对陇东乔化密闭富士苹果园树体叶片光合、荧光及果实品质的影响，以15年生密闭红富士苹果园为研究对象，对树体叶片光合、荧光参数和果实品质等指标进行测定分析。结果表明，间伐改形不但可以显著提高苹果叶片光合能力，也可以显著提高果实品质。间伐改形后，树体叶片净光合速率、蒸腾速率、气孔导度分别比不采取间伐提高了12.4%、8.3%、17.4%；间伐树体叶片的PSⅡ非光化学猝灭系数和最大荧光产量比不采取间伐提高了3.0%、1.5%；叶片的吸收光能、还原QA能量和电子传递能量分别比不采取间伐提高10.4%、5.5%、6.3%；果实单果重、着色面积、硬度、可溶性固形物、可滴定酸均显著高于不采取间伐处理。

In order to study thinning and reshaping effects on leaf photosynthesis，fluorescence and fruit quality，15 year-old Fuji apple dense orchards were selected to measure the photosynthetic，fluorescence and fruit quality，before and after the thinning and reshaping practices. The results showed that thinning and reshaping could not only improve the photosynthetic capacity of apple leaves，but also improve the fruit quality. After thinning and reshaping，compared with the control no thinning(CK)，the net photosynthetic rate，transpiration rate，and stoma conductance increased by 12.4%，8.3%，17.4%；qN(non-photochemical quenching coefficient)and Fm(maximum fluorescence)of PSⅡ of leaves increased by 3.0% and 1.5%，TRo/RC(energy captured by the unit reaction center to reduce QA)and ETo/RC were increased 10.4%，5.5%，and 6.3%，respectively. And the main indicators of single fruit weight，coloring area，hardness，soluble solids，and titratable acid were significantly higher than CK.

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国家自然科学基金项目(31760556)；国家苹果产业技术体系平凉综合试验站项目(GARS-27)；国家重点研发计划项目(2016YFD0201135)；农业农村部西北地区果树科学观测试验站项目(S-10-18)；甘肃省苹果产业科技攻关项目(GPCK 2011-1)。