钙素和水分亏缺对黄瓜叶片细胞质膜透性的影响  

THE EFFECTS OF CALCIUM AND WATER DEFICIENCY ON THE PLASMA MEMBRANE PERMEABILITY OF CUCUMBER LEAVES

作　　者：杨根平[1] 高爱丽[1] 荆家海[1] 

机构地区：[1]西北农业大学植物生理研究室,陕西杨陵712100

出　　处：《西北植物学报》1993年第2期89-95,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金

摘　　要：用控制溶液的钙量[加或不加Ca(NO_3)_2]和渗透势(加聚乙二醇6000,202 g/L)的方法,研究了钙素和水分亏缺对黄瓜叶片细胞质膜透性的影响。结果表明:在渗透胁迫下,正常供钙的黄瓜叶片相对含水量(RWC)和膜透性变化较小、MDA增加不显著、SOD活性无明显改变;缺钙植株叶片的RWC随渗透胁迫处理线性下降,膜透性显著增大、MDA含量迅速提高、SOD活性也升高。在正常水分供应下,与供钙植株相比,缺钙植株SOD活性和MDA含量均较高,但RWC和膜透性无差异。在水分胁迫下,缺钙植株MDA和质膜透性与ΔRWC以及MDA与质膜透性之间均呈正相关。这些结果表明在水分胁迫下,缺钙处理叶片保水能力降低,使受害加重;同时,细胞质膜的稳定性降低。膜透性改变可能与在水分胁迫下体内的膜脂过氧化反应密切相关,即缺钙加速了膜脂过氧化反应,从而损害了质膜结构。The effects of calcium and water deficiency on the plasma membrane ( PM ) permeability of cucumber (Cucumis sativus L. ) leaves were studied by controling the Ca^(2+) level(with or without Ca(NO_3)_2 in the cultural solution)and osmotic potential(Polyethylene glycol 6000, 202g/L).The RWC and PM permeability of Ca^(2+)-treated leaves changed slightly and the MDA content and SOD activity of them went up less obviously after osmotic stress.The RWC of Ca^(2+)-deficient leaves, however, declined linearly with time, PM permeability increased greatly and the MDA content and SOD activity also increased. Under the normal water condition the SOD activity and MDA content of Ca^(2+)deficient leaves were higher than that of Ca^(2+) - treated, but RWC and PM permeability were not different from that of Ca^(2+)-treated.Under water stress,the MDA content and PM permeability of Ca^(2+)-dificient leaves were correlated with the RWC(correlative coefficients were 0.992 and 0.979, respectively)and MDA content was also correlated with the PM permeability. These results showed that water retention ability of Ca^(2+)-deficient leaves reduced, it's PM stability declined, and it's permeability might be related closely to the membrane lipid peroxidation, in other words, Ca^(2+)-dificient treatment stimulated lipid peroxidation in the membrane and thus damaged it's active structure.

关 键 词：钙 水分胁迫 质膜透性 黄瓜 

分 类 号：S642.201[农业科学—蔬菜学]