摘要
在盆栽自然水分干旱胁迫条件下,研究了接种链格孢菌(Alternaria tenuis Nees)对白车轴草(Trifolium repens L.)抗旱性相关的生理生化指标的影响,结果表明:接种组与对照组叶片的电导率(EC)、丙二醛(MDA)含量、脯氨酸(Pro)含量均与干旱处理时间呈显著正相关,而叶片相对含水量(RWC)、抗坏血酸(ASA)含量与处理时间呈显著负相关。链格孢菌的侵染能促进干旱胁迫下白车轴草叶片EC和MDA含量的增加,延缓Pro的积累,加速叶片RWC和ASA含量的降低。到达干旱处理的第6天,接种组的EC、MDA含量分别比对照高20.06%、68.79%(p<0.05),而RWC、Pro含量和ASA含量分别比对照低7.03%、25.3%、77.43%(p<0.05)。此外,接种组超氧化物歧化酶(SOD)、过氧化物酶(POD)活性均于处理的第4天开始显著低于对照;过氧化氢酶(CAT)活性也于处理的第6天下降并显著低于对照,为对照的79.79%(p<0.01)。表明链格孢菌会降低干旱胁迫下白车轴草的渗透调节能力和保护酶的活性,加剧活性氧的积累和膜脂过氧化程度,使白车轴草的抗旱性降低。
Through pot cultivation experiments of Trifolium repens L. under natural water stress, we studied the effects of.41ternaria tenuis Nees colonization on the physiological and biochemical characteristics that were related to the drought resistance of Trifolium repens L.. The results showed that the electric conductivity （EC）, malondialdehyde （MDA） content and proline content were positively related to drought time, whereas the leaves＇relative water content （RWC） and free ascorbic acid （ASA） content were negatively related to it. Compared with those in noninoculated plants, the.4.tenuis colonization can significantly accelerate the rising of EC, MDA content of T.repens and alleviate the accumulation of proline in T.repens under draught stress. Moreover, the contents reduction trends of RWC and ASA in inoculated plants were apparently accelerated. By the end of the experiment, EC and MDA content in inoculated plants were 20.06% and 68.79% higher than that in noninoculated plants, while RWC, proline and ASA content were lower by 7.03%, 25.3% and 77.43%, respectively. Besides, activities of superoxide dismutase （SOD）and peroxidase （POD） in inoculated plants were lower or significantly lower than that in noninoculated plants from the forth day; the catalase （CAT） activity declined rapidly and lower significantly than that in noninoculated plants at the sixth day. The results suggested that under natural water stress, the A.tenuis colonization could depress the osmo-regulatory response of T.repens, lower its protective enzyme activities, aggravate the accumulation of active oxygen and resulted oxidative damage to membrane lipids. Consequently, the drought resistance of inoculated T.repens was depressed.
出处
《生态环境》
CSCD
北大核心
2007年第5期1460-1465,共6页
Ecology and Environmnet
基金
国家自然科学基金项目(30470270)
中国科学院开放研究室基金项目
安徽省高校青年教师资助基金项目(2005JP1054)
关键词
白车轴草
链格孢菌
干旱胁迫
抗旱性
Trifolium repens L
Alternaria tenuis Nees
drought stress
resistance
