干旱胁迫下外源海藻糖对糯玉米幼苗根系和叶片抗氧化系统及渗透调节物质的影响
本研究以苏玉糯5号为供试材料,研究干旱胁迫条件下外源海藻糖对糯玉米幼苗根系和叶片抗氧化系统及渗透调节物质的影响。结果表明：干旱胁迫显著降低叶片叶绿素含量和根系活力,喷施外源海藻糖后这两类物质含量增加。干旱胁迫下喷施外源海藻糖增加了玉米根系和叶片中可溶性蛋白、可溶性糖、抗坏血酸(AsA)、还原型谷胱甘肽(GSH)含量,增强了糯玉米幼苗根系和叶片的抗氧化酶如超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化物酶(POD)与过氧化氢酶(CAT)活性,降低了超氧阴离子产生速率(O2-)、丙二醛(MDA)和脯氨酸(PRO)含量,外源海藻糖处理下叶片中可溶性糖、可溶性蛋白、AsA和GSH含量增加幅度大于根系,叶片中丙二醛含量降幅大于根系。表明喷施外源海藻糖缓解干旱胁迫对叶片伤害效果大于根系。综上,干旱胁迫下喷施外源海藻糖能够调节糯玉米幼苗渗透调节物质,提高抗氧化酶活性能力,增强糯玉米抗旱能力,减小干旱伤害。
英文摘要:
The effects of exogenous trehalose on antioxidant system and osmotic adjustment substances in root and leaf of waxy maize seedlings under drought stress were clarified using Suyunuo 5 as material. The results showed that drought stress significantly decreased the leaf chlorophyll content and root activity, while application of exogenous trehalose increased those contents. Application of exogenous trehalose under drought conditions could up-regulating the activities of antioxidant enzymes such as superoxide dismutase (SOD), ascorbic acid peroxidase (APX), peroxidase (POD) and catalase (CAT) in root and leaf of waxy maize seedlings. Spraying of exogenous trehalose could reduce the production rate of superoxide anion (O2-) and contents of malondialdehyde (MDA) and proline (PRO), whereas the contents of soluble protein and sugar, ascorbic acid (AsA) and glutathione (GSH) were increased significantly. The increase of soluble sugar and protein, AsA and GSH contents in leaves were more pronounced than those in roots, and the malondialdehyde content in leaves decreased greater than that in roots, indicated that alleviation of exogenous trehalose spraying were more pronounced in leaf than in root under water deficit conditions. In conclusion, when waxy maize seedlings suffer drought stress, application of exogenous trehalose could upregulate the antioxidant enzymes activities, adjust osmotic substances, enhance the drought resistance and alleviate the drought damage.
查看全文
;
