低温处理葡萄根系对叶片PSII活性的影响

Effect of Low Temperature Treatments in Root of Grapevine on PSII Activity in Leaves

以美乐葡萄(Vitis vinifera cv.‘Merlot’)幼苗为试材,对叶片进行霜冻胁迫的同时控制土壤降温过程,造成根系冷胁迫(2°C)和冻胁迫(0°C)。测定霜冻胁迫后和恢复期间叶片的快速叶绿素荧光参数,并分析低温胁迫不同根系对叶片霜冻害程度的影响。结果表明,根系在不同低温胁迫下会影响叶片对霜冻的反应,根系冻胁迫造成叶片严重的霜冻伤害,光系统II(PSII)反应中心活性难以得到恢复;根系冷胁迫能避免叶片严重的低温伤害,低温胁迫后PSII的活性也能很快恢复。

Vitis vinifera cv. ‘Merlot＇ roots undergo freezing stress（0°C） or chilling stress（2°C） during cold treatment of grapevine leaves. Fast chlorophyll fluorescence was measured after cold treatment and used to analyze the effect of low root temperature on frost damage in leaves. Low root temperature to different extents led to different frost damage on leaves. Freezing stress（0°C） on roots led to more severe damage on leaves with cold treatment; this kind of damage to PSII was unable to recover. Chilling stress（2°C） applied to roots prevented the severe damage to leaves and was beneficial for recovery in PSII.