PJB-2019-241
Pruning effects on sap flow and sugar phloem unloading in current-year shoots of different aged grapevine shoots
Xianhua Zhao, Liyuan Liu, Hua Li and Cuixia Li
Abstract
The study aimed at providing an efficient and sustainable pruning technique and theory for high quality and stable yield in grape production, sap flow rate in current-year shoots on different aged grapevines, photosynthetic rate of leaves, pruning-induced tylose development in vessel, and the sugar phloem unloading in grape berries. It was found that the sap flow rate changed rapidly with the increase of the water transport distance and changed dramatically with the increasing age of the shoots. The photosynthetic rate and the sugar phloem unloading trend in all treatments were basically remained the same. As the distance of water transportation increased, the sugar phloem unloading in grape berries on the older shoots was significantly lower than that on the younger ones. Tyloses were found in the vessel after pruning, and the vessel partly or completely blocked by tyloses at the wound would continue to increase over time. The results showed that the changes of sap flow rate, photosynthetic rate and sugar phloem unloading were not simultaneous. With the extension of the perennial part, the resistance of water transport became greater; the amount of sugar phloem unloading in berries also decreased with the extension of the perennial part. The study proposed the number of cuts and the length of perennial parts should be minimized without affecting the quality, stability, and sustainability of grape production.
To Cite this article:
Zhao, X., L. Liu, H. Li and C. Li. 2021. Pruning effects on sap flow and sugar phloem unloading in current-year shoots of different aged grapevine shoots. Pak. J. Bot., 53(3): DOI: http://dx.doi.org/10.30848/PJB2021-3(9)
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