Drought stress hinders photosynthesis and phloem transport in leaves, which limits the loading and long-distance transport of photosynthates in leaves. Especially for deciduous trees at leafless stage, non-leafy photosynthesis may be of great significance to in-situ embolization repair of stems and branches xylem. It has been proved that photosynthesis of bark of branches can promote xylem embolization repair by mediating water absorption of bark, which plays a key role in maintaining water conveyance function of branches. In this study, the isolated branches of Salix matsudana were used as experimental materials. After reaching the preset water potential and PLC gradient, they were treated with immersion in water, and the contribution of cortical photosynthesis to xylem embolism repair was studied by immersion treatment at different times. It was found that the embolism vulnerability curve of Salix matsudana was "S" shape, P50 was-1. 93 MPa, and Salix matsudana had strong anti-embolism ability; the absolute water content of bark and xylem of Salix matsudana branches was significantly increased, the volume ratio of xylem vessel sap was significantly increased, PLC was significantly reduced, and exogenous water could enter xylem vessel through bark to repair embolism.

Yu Yongchang, Yue Junsheng, Ge Xinyu, Wang Lili, Liang Wei. Effects of water absorption by bark on embolization repair of plant xylem. Academic Journal of Agriculture & Life Sciences (2022) Vol. 3 Issue 1: 1-6. https://doi.org/10.25236/AJALS.2022.030101.

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