干旱胁迫下玉米幼苗对外源壳寡糖处理的生理响应

Physiological Response of Maize Seedlings to Exogenous Chitosan under Drought Stress

为明确干旱胁迫下玉米幼苗对外源壳寡糖处理的生理响应,以先玉335为供试材料,研究干旱胁迫下叶面喷施壳寡糖对玉米幼苗生长、抗氧化系统及渗透调节物质的影响。结果表明,干旱胁迫显著影响玉米植株的生长,显著降低叶片叶绿素的含量;而喷施壳寡糖能有效地缓解干旱带来的生长抑制作用,增加叶绿素含量。干旱胁迫下喷施壳寡糖,能显著地降低过氧化氢、MDA含量,增强抗氧化酶活性(SOD、POD、CAT、APX),缓解干旱胁迫对细胞膜的伤害。同时,喷施壳寡糖能显著提高叶片内脯氨酸、可溶性糖、可溶性蛋白含量,从而提高叶片的保水能力。因此,壳寡糖可通过降低植株的氧化损伤和提高保水能力来改善玉米幼苗对干旱胁迫的适应,从而提高其抗旱能力。

In order to clarify the physiological response of maize seedlings to exogenous chitosan under drought stress,Xianyu 335 was used as the test material to study the effects of foliar spraying chitosan on the growth,anti⁃oxidant system and osmotic adjustment substances of maize seedlings under drought stress.Influence.The results showed that drought stress significantly affected plant growth and significantly reduced the chlorophyll content of leaves.Spraying oligochitosan could effectively alleviate the growth inhibition caused by drought and increase the chlorophyll content.Spraying oligochitosan under drought stress can significantly reduce the content of hydrogen peroxide and MDA,enhance the activity of antioxidant enzymes(SOD,POD,CAT,APX),and alleviate the dam⁃age of drought stress to cell membranes.At the same time,spraying oligochitosan can significantly increase the con⁃tent of proline,soluble sugar and soluble protein in the leaves,thereby improving the water retention capacity of the leaves.Therefore,chitooligosaccharides can improve the adaptation of maize seedlings to drought stress by re⁃ducing the oxidative damage of plants and increasing the water retention capacity,thereby enhancing its drought re⁃sistance.