摘要
为探讨信号分子过氧化氢(H 2 O 2 )对干旱胁迫下裸燕麦生理响应的调控机制,以砂培白燕7号幼苗为材料,研究了喷施0.01 mmol·L -1 H 2 O 2 对17.8%聚乙二醇6000模拟的干旱胁迫下叶片光合特性、活性氧代谢、渗透调节物质积累和幼苗生长的影响。结果表明:喷施H 2 O 2 后,干旱胁迫下的裸燕麦幼苗叶片叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量和叶绿素a/b较对照(喷H 2 O后干旱胁迫)分别提高了20.0%、12.9%、18.5%、8.1%和24.3%,叶片净光合速率、气孔导度、胞间CO 2 浓度和水分利用效率分别提高了20.6%、25.9%、12.0%和33.8%,蒸腾速率降低了9.7%;喷施H 2 O 2 还使干旱胁迫下裸燕麦幼苗叶片的过氧化氢酶、抗坏血酸过氧化物酶活性和抗坏血酸含量分别提高了113.5%、102.9%和13.8%,而超氧化物歧化酶、过氧化物酶活性及O —· 2 、H 2 O 2 、丙二醛含量和细胞膜相对透性分别下降了21.5%、60.4%、29.3%、38.4%、19.7%和14.2%,可溶性蛋白质、可溶性糖、游离氨基酸和脯氨酸含量分别上升了10.5%、40.3%、13.8%和17.2%,幼苗株高、根长、植株鲜重、植株干重和相对含水量分别提高了14.8%、25.0%、20.1%、11.0%和5.93 %,但谷胱甘肽含量没有显著变化。表明外源H 2 O 2 能够通过降低膜脂过氧化程度和促进渗透溶质积累,改善叶片光合功能和植株水分状况,从而减轻干旱对裸燕麦幼苗生长的抑制,增强裸燕麦的抗旱性。
To explore the regulative mechanism of hydrogen peroxide (H 2 O 2 ), a signaling molecule for the physiological response of Avena nuda L.(naked oats) seedlings under drought stress. In this study, a sand culture experiment was conducted to investigate the effect of spraying 0.01 mmol·L -1 H 2 O 2 on leaves photosynthesis, active oxygen metabolism, osmotic regulation substances accumulation, and growth of ‘Baiyan 7’ Avena nuda L. seedlings under drought stress simulated by 17.8% polyethylene glycol 6000. The results showed that chlorophyll a, chlorophyll b, total chlorophyll, carotenoid contents, and chlorophyll a/b in leaves of naked oats seedlings under drought stress after spraying with H 2 O 2 increased by 20.0%, 12.9%, 18.5%, 8.1%, and 24.3%, respectively, over the control (drought stress spraying distilled water). In addition,the net photosynthetic rate, stomatal conductance, intercellular CO 2 concentration, and water use efficiency in leaves increased by 20.6%, 25.9%, 12.0%, and 33.8%, respectively, whereas the transpiration rate decreased by 9.7%. Moreover, the catalase, ascorbate peroxidase activities, and ascorbic acid content in the leaves under drought stress after spraying with H 2 O 2 increased by 113.5%, 102.9%, and 13.8%, respectively, and the activities of superoxide dismutase, peroxidase, the contents of O -· 2 , H 2 O 2 , malondialdehyde (MDA), and relative plasma membrane permeability in leaves decreased by 21.5%, 60.4%, 29.3%, 38.4%, 19.7%, and 14.2%, respectively. The contents of soluble protein, soluble sugar, free amino acid, and proline in leaves increased by 10.5%, 40.3%, 13.8%, and 17.2%, respectively, and plant height, root length, fresh weight, dry weight, and relative water content of naked oats seedlings increased by 14.8%, 25.0%, 20.1%, 11.0%, and 5.93%, respectively, but there were no significant changes in glutathione content. These results indicated that exogenous H 2 O 2 reduced the inhibition of drought stress on growth of naked oats seedlings, enhanced the drought resis
作者
刘建新
欧晓彬
王金成
LIU Jian-xin;OU Xiao-bin;WANG Jin-cheng(Provincial Key Laboratory for Protection andUtilization of Longdong Bio-resources in Gansu Province, Qingyang, Gansu 741500, China)
出处
《干旱地区农业研究》
CSCD
北大核心
2019年第4期146-153,共8页
Agricultural Research in the Arid Areas
基金
国家自然科学基金项目(31560125)
甘肃省庆阳市科技计划项目(KZ2014-19)
关键词
过氧化氢
裸燕麦
干旱胁迫
生理特性
hydrogen peroxide
naked oats ( Avena nuda L.)
drought stress
physiological characteristics
