干旱胁迫下桃树各部位贮存水调节能力的研究

Study on the adjustment of reserved water in different part of nectarine tree in drought stress

干旱胁迫使桃品种瑞光5号(Prunuspersicavar.nectarinacv.RuiguangNo.5)的叶片水势和茎流下降,并且干旱越严重下降越多。干旱胁迫对贮存水调节量的影响不显著,但是绝对调节能力随干旱胁迫程度的增加而增加。各部位间的相对调节能力主要是由其水容、贮存水阻力和体积决定的,干旱胁迫对各部位间的相对调节能力的影响不显著。在充分灌水条件下各部位贮存水夜间的相对调节能力为:主根18.8%、主干38.5%、枝条17.8%、叶片3.4%、细根2.9%、果实6.7%、粗根12.0%,处理之间绝对调节能力的差异不显著。贮存水的调节主要来自主干、主根、粗根和枝条,这4部分占全部调节量的80%以上。

The leaf water potential and sap flow in different part of the tree of Ruiguang 5 nectarine cultivar （Prunus persica var. nectarina Maxim.） became lower when in drought stress. It was lightly influenced by bulk of reserved water adjustment in drought stress, but the absolute reserved water adjustment was depended on sap flow, which influenced by soil water conditions. The relative reserved water adjustment was not evidently influenced in different part of the tree, which depended on water capacity, reserved water resistance and bulk of the part. The relative reserved water adjustments in different part of control were： main root 18.8%, stem 38.5%, branch 17.8%, leaves 3.4%, fine root 2.9%, fruit 6.7%, thick root 12.0% in night. There was no difference among different treatments in relative reserved water adjustment. Above 80% adjustment was adjusted by stem, main root, thick root and branch.