根系修剪对苹果树光合特性及果实品质的影响

为探讨适宜的根剪时期,以18 a矮化中间砧长富2号苹果树为试材,进行了秋季、萌芽期及花后根剪处理,测定了叶片光合特性与果实品质。结果表明,根剪提高了树体叶片的净光合速率、气孔导度及胞间二氧化碳浓度,在生长季前期,降低了蒸腾速率,提高了水分利用率,生长季后期各处理差异较小,其中秋季根剪光合能力的提高优于其它处理。根剪处理有利于提高果实可溶性固形物、可滴定酸、维生素C及果皮花青苷含量,果面鲜艳程度高,果肉硬度较大。综合分析认为,秋季根剪对提高叶片光合特性与果实品质更为适宜。

Effects of Root System Pruning on Photosynthetic Characteristics and Fruit Quality of Apple Tree

Chang Fu II apple tree with 18-year-old dwarfing interstock were used as experimental materials, which were subjected to root system pruning in different developmental stages, such late growth stage(autumn), sprouting stage and post-anthesis to investigate suitable periods of root system pruning. Photosynthetic characteristics of the leaves and fruit quality were measured. The results showed that root system pruning improved photosynthetic rate, stomatal conductance and intercellular CO₂ concentration. In the early growing season, root pruning reduced transpiration rate and improved water use efficiency, but there were little differences among treatments in late growing season. Root pruning in autumn had better photosynthetic capabilities to other treatments. Root pruning was conducive to improve fruit soluble solid, acid, vitamin C and anthocyanin contents, and the vividness of fruit surface and firmness of fruit were better. Autumn root pruning had better performance. Comprehensive analysis showed that autumn root pruning was more suitable on improving photosynthetic characteristics of leaves and fruit quality.