Changes in Sucrose and Sorbitol Metabolism Cause Differences in the Intrinsic Quality of Peach Fruits Cultivated in Field and Greenhouse Environments

Fruit trees grow in complex environments where various environmental factors are related to each other, exerting a comprehensive effect on fruit quality. In this study, diurnal variations in environmental indices in the field and greenhouse were recorded, and the changes of leaf photosynthetic assimilate metabolism and fruit soluble sugar accumulation in peach (Prunus persica) under the influence of a comprehensive environment were explored. The results showed that the field environment was more favorable for peach photosynthesis, and more sucrose, glucose and fructose could be accumulated compared with the greenhouse environment. In addition, more sorbitol was converted into glucose and fructose in field fruits. Therefore, field fruits exhibited a particularly greater increase in the fructose content, which greatly increased the sweetness of field fruits. This study revealed changes in the pattern of sucrose and sorbitol metabolism in peaches grown in the field and greenhouse, and analyzed the possible reasons and mechanisms of fruit intrinsic quality differences. This research will provide a theoretical basis and reference for the regulation of fruit quality in the greenhouse environment.