干旱胁迫对沙枣和孩儿拳头的生理特性的影响  

Physiological Characteristics of Elaeagnus angustifolia and Grewia biloba G.Don var.parviflora Seedlings under Drought Stress

作　　者：孙景宽[1] 张文辉[1] 刘新成[1] 

机构地区：[1]天津师范大学化学与生命科学学院

出　　处：《西北植物学报》2008年第9期1868-1874,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：天津市科技发展项目(05YFGZNC01200);滨州学院青年人才创新工程(BZXYQNLG200721)

摘　　要：以沙枣和孩儿拳头2年生盆栽苗为材料,采用称重控水的方法对4个梯度土壤干旱胁迫条件对沙枣和孩儿拳头生理特性的影响进行了研究.结果显示：（1）干旱胁迫造成了两物种体内水分的严重亏缺,重度胁迫（6.4%～8.0%）下,两物种自然饱和亏为对照的3～4倍;同一干旱胁迫梯度下沙枣自然饱和亏总高于孩儿拳头,但水分临界饱和亏和需水程度低于孩儿拳头;沙枣自由水含量随干旱胁迫加剧下降幅度较大,自由水向束缚水转化率较高;沙枣最高水势的下降幅度低于孩儿拳头,最低水势的下降幅度高于孩儿拳头,且沙枣的绝对水势比孩儿拳头低.（2）随着干旱胁迫程度的加剧,两物种叶片中的脯氨酸含量、可溶性总糖含量均有不同程度的增加,特别是在重度干旱胁迫下,脯氨酸含量高出对照4倍多,且孩儿拳头脯氨酸含量明显高于沙枣,但可溶性总糖含量低于沙枣;沙枣本身的可溶性蛋白含量较孩儿拳头高,随干旱胁迫的加重沙枣的可溶性蛋白含量先增加后下降,而孩儿拳头逐渐下降.结果表明,沙枣和孩儿拳头对干旱胁迫均具有积极的水分生理响应方式,推测两种植物的水分耐受极限为6.4%～8.0%,但物种间生理响应方式存在差异,沙枣较孩儿拳头具有更强的防御干旱的生理机制.Elaeagnus angustifolia and Grewia biloba G. Don var. parviflora 2-year-old seedlings as materials,we used weighing method to set up four level soil moisture. The physiological characteristics of E. angustifolia and Grewia biloba G. Don var. parviflora seedlings were studied. The results showed： （1） Drought stress causing the serious water deficiency in the two species and their natural saturation deficit was three to four times CK under severe stress. At the same drought stress level,E, angustifolia natural saturation deficit was higher than that of Grewia biloba G. Don var. parviflora,but the critical water saturation deficit and requirement level of water were reverse. With the drought stress increasing, free water content of E. angustifolia declined largely, more and more free water turned into the bound water. The highest water potential of E. angustifolia declined in less than that of Grewia biloba G. Don var. parviflora. The lowest water potential was reverse and the absolute water potential of E. angustifolia was lower than that of Grewia biloba G. Don var. parviflora. （2）With drought stress increasing, the contents of proline and total soluble sugar of the two species in the leaves increased to a certain extent. Especially under T3 stress,proline content was higher than that of CK for four times,and Grewia biloba G. Don var. parviflora proline content was significantly higher than that of E. angustifolia, but the total soluble sugar content was less than that of E. angustifolia;With drought stress increasing,the soluble protein content of E. angustifolia firstly increased,and then declined, but Grewia biloba G. Don var. parviflora gradually declined. E. angustifolia itself had a high content of soluble protein, which was less impacted by drought stress. （3）Physiological characteristics of the two species had positive responses to drought stress, speculating the limit of tolerance is 6.4-8.0% ;The species were different in physiological response and E. angustifolia was more advantaged. Theref

关 键 词：沙枣 孩儿拳头 水分平衡 渗透调节 干旱胁迫 

分 类 号：Q945.78[生物学—植物学]