Embolism destroys the water conveyance function of ducts, reduces the hydraulic conductivity of xylem, and leads to the closure of stomata and the obstruction of photosynthesis in leaves. Therefore, in-situ repair of xylem embolism is very important to ensure the water conveyance function of catheter. Osmotic adjustment is the main driving force for in-situ repair of xylem embolism. Soluble sugars act as apoplast chemical signals and act as osmotic adjustment substances to mediate osmotic driving force during osmotic adjustment-driven catheter refilling. In this study, the isolated branches of Salix matsudana were treated with light and darkness at different times after natural drought and water loss, reaching the preset water potential. By analyzing the NSC changes of branches under different treatment conditions, the dynamics and mechanism of cortical photosynthesis on in-situ repair of woody plant embolism were analyzed. It was found that cortical photosynthesis increased the starch and soluble sugar content in bark and xylem of Salix matsudana branches, and provided a non-structural carbohydrate source for embolic catheter refilling.

Yu Yongchang, Yue Junsheng, Ge Xinyu, Wang Lili, Liang Wei. Effects of Cortical Photosynthesis on NSC Content in Salix matsudana Branches. Academic Journal of Agriculture & Life Sciences (2022) Vol. 3 Issue 1: 7-11. https://doi.org/10.25236/AJALS.2022.030102.

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