亚精胺浸种对渗透胁迫下玉米幼苗叶片类囊体膜上结合态多胺含量的影响

Effects of Soaking Seeds with Spermidine on the Content of Conjugated Spermidine in the Thylakoid Membrane in the Leaves of Maize Seedlings under Osmotic Stress

[目的]探讨多胺增强植物抗旱性的机理。[方法]用亚精胺(spermidine:Spd)浸种,检测了渗透胁迫下玉米品种农大108(抗旱性较强)和掖单13(抗旱性较弱)幼苗叶片中类囊体膜上结合态多胺含量的变化。[结果]渗透胁迫7 d,抗旱性弱的掖单13玉米幼苗叶片的相对含水量和类囊体膜上非共价结合态亚精胺含量的下降幅度明显大于抗旱性较强的品种农大108;Spd浸种处理,不仅明显抑制掖单13在胁迫条件下其幼苗叶片相对含水量的下降,并且明显抑制其在胁迫条件下类囊体膜上非共价结合态亚精胺含量的下降。[结论]Spd浸种,通过抑制渗透胁迫下玉米幼苗类囊体膜上非共价结合态亚精胺含量的下降,提高玉米(特别是抗旱性较弱的品种)幼苗的抗渗透胁迫能力。

[Objective] The research aimed to discuss the mechanism of enhancing the tolerance of plants to drought stress by using polyamine. [Method] The maize seeds were soaked with spermidine to detect the changes of conjugated polyamine content in the thylakoid membrane in the seedling leaves of two maize cultivars, Nongda 108 （strong drought-tolerant） and Yedan 13 （dronght-semitive） under osmotic stress. [Result] On the 7th day, rel- ative water content and the content of noncovalently conjugated spennidine in the thylakoid membrane in the seedling leaves of Yedan 13 decreased more significantly that in Nongda 108. Treatment of soaking seeds with Spd resulted in obvious inhibition of the decreases of relative water content and the con- tent of noncovalently conjugated spermidine in the seedlings leaves of Yedan 13 under osmotic stress. [Conclusion] Soaking seeds with Spd could enhance the tolerance of naize seedlings to osmotic stress by inhibiting the decrease of noncovalently conjugated spennidinc content in the thylakoid membrane in the leaves of maize seedling.