无核白鸡心葡萄离体叶水势与叶柄木质部液流的关系

Relation of leaf water potentials with petiole xylem sap flow of excised leaves in grapevine

以无核白鸡心葡萄(Vitis vinifera L.)离体叶为试材,研究了叶水势与叶柄木质部液流通量、液流速率和液流压力梯度之间的关系。结果表明:0^-0.9 MPa范围内,在葡萄离体叶水势与叶柄木质部液流压力梯度(R2=0.958 9)之间的关系比与叶柄木质部液流通量(R2=0.668 4)和液流速率(R2=0.694 6)之间的关系更密切;因此,通过测定叶柄木质部液流压力梯度有可能提供一种比较准确敏捷地监测植物叶动态水势的新方法。

This paper reports the relations of leaf water potentials with petiole xylem sap flow of excised leaves in grapevine （Vitis vinifera L. ）. Leaf water potential, ranging 0-0.9 MPa, was reversely and much closely related with sap pressure gradient（R^2=0. 958 9）, comparing that with sap flow rate（R^2 =0. 668 4） and sap flow velocity（R^2 = 0. 694 6） in the xylem of petioles. It may be thus concluded that xylem sap pressure gradient can be used as a novel alternative parameter to monitor dynamic leaf water potential in plants.