Variable fall temperature and moisture conditions may alter leaf senescence of deciduous fruit trees, influencing carbon assimilation before dormancy and phenology the following spring. This study explored gas exchange of young peach trees (Prunus persica (L.) Batsch) when senescence proceeded normally or was delayed during the fall under two soil moisture treatments: Well-irrigated trees or water deficit. Results showed leaf carbon assimilation was similar between the senescence treatments, but whole tree assimilation was estimated to be greater in delayed senescence trees compared to normal senescence trees based on timing of defoliation and total leaf area. The effect of soil moisture on carbon assimilation was not consistent between years. Delayed sap flow and bloom time resulted as a consequence of delayed senescence the previous fall, but soil moisture did not affect spring phenology.

中文翻译：

---

秋季气候条件对桃树碳同化和春季物候的影响

秋季温度和湿度条件的变化可能会改变落叶果树的叶片衰老，影响到春季之后休眠和物候发生之前的碳同化。这项研究探索了年轻桃树（李属桃）的气体交换（L.）Batsch）在两种土壤水分处理下，衰老正常进行或在秋天期间延迟：灌溉良好的树木或缺水。结果显示，在衰老处理之间，叶片碳的同化作用相似，但根据落叶时间和总叶面积，与正常衰老树相比，延迟衰老树中的整棵树同化作用估计更大。年间土壤水分对碳同化的影响不一致。先前秋天的衰老延迟导致了汁液流动和开花时间的延迟，但土壤水分并未影响春季的物候。