《植物生理学报》 2018, 54(5): 837-844

粗壮女贞对持续性干旱及复水的生理响应

吴丽丽, 王德炉^*, 李自玉

贵州大学林学院, 贵阳550025

通信作者：王德炉；E-mail: 1539349567@qq.com

摘　要：

为了探讨粗壮女贞(Ligustrum robustum)幼苗对持续干旱胁迫的适应能力、恢复能力及生理响应特征, 采用温室盆栽方法模拟土壤干旱条件, 分别对干旱胁迫5、10、15、20和25 d及胁迫后复水5、10、20 d的幼苗渗透调节物质含量、叶片相对电导率(REC)、水分饱和亏(WSD)、丙二醛(MDA)含量及保护酶活性的变化规律进行研究。结果表明: 干旱胁迫对粗壮女贞叶片生理指标有显著影响, 复水后, 各指标均有向正常水平恢复的趋势。随着干旱时间的延长, 粗壮女贞叶片脯氨酸(Pro)含量、REC、WSD等指标呈增加趋势; 可溶性蛋白质含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性呈先升后降的变化, 但两种保护酶活性增幅和响应时间不同, 表现出不同的清除过氧化物功能; MDA含量呈“升-降-升”的波浪式趋势。干旱胁迫的程度不同, 幼苗复水后各指标恢复能力和恢复程度各异, 干旱时间越长, 恢复需要的时间也越长, 各指标恢复时间与干旱程度呈正相关。综合表明, 土壤相对含水量为32.51%是粗壮女贞正常生长所需最低土壤含水量。

关键词：粗壮女贞; 生理响应; 干旱胁迫; 复水

收稿：2018-01-23   修定：2018-04-18

资助：贵州省农业科技攻关项目(黔科合NY字[2007]3040号)、贵州省自然科学基金(黔科合J[2007]2059号)和贵州省优秀科技教育人才省长专项基金(黔省专合字[2006]5号)。 * 通讯作者(1539349567@qq.com)。

Physiological response of Ligustrum robustum to continuous drought and rewatering

WU Li-Li, WANG De-Lu^*, LI Zi-Yu

Forestry College, Guizhou University, Guiyang 550025, China

Corresponding author: WANG De-Lu; E-mail: 1539349567@qq.com

Abstract:

To investigate adaptive ability, recovering ability and physiological characters of Ligustrum robustum seedlings to continuous drought stress, greenhouse-pot culture method was adopted to simulate soil drought conditions, and analyze variation patterns in content of osmotic adjustment substances, leaf relative electrical conductivity (REC), water saturation deficit (WSD), malondialdehyde (MDA) content and protective enzyme activities of seedlings after exposure to drought stress (for 5, 10, 15, 20 and 25 days) and rewatering (5, 10 and 15 days) treatments. Results show that drought stress had significant influences on physiological indexes of leaves of L. robustum, and all indexes tended to recover towards normal levels after being rewatered. As drought stress prolonged, proline (Pro) content, REC and WSD of L. robustum increased; soluble protein content and activities of SOD and POD first increased and then decreased, but the degree of increase and response time differed, exhibiting different functions of peroxide scavenging; MDA content tended to increase, decrease and re-increase. As drought stress continued, the recovering ability and extent of various indexes were different after seedlings were rewatered. Their recovery time increased as drought lasted longer, and recovery time of indexes positively correlated with the extent of drought stress. The 32.51% of soil relative water content was the threshold for the normal growth of L. robustum.

Key words: Ligustrum robustum; physiological response; drought stress; rewatering