《植物生理学报》 2015, 51(5): 702-708

水分胁迫及复水对不同耐旱性玉米生理特性的影响

刘承, 李佐同^*, 杨克军^*, 徐晶宇, 王玉凤, 赵长江, 张翼飞, 李竹, 孙少慧, 富士江, 赵莹, 谷英楠, 付健, 方永江, 刘瑀, 张发明, 马丽峰, 石新新

黑龙江八一农垦大学农学院寒地作物种质改良与栽培重点实验室, 黑龙江大庆163319

通信作者：李佐同；E-mail: lxg6401999@163.com, byndykj@163.com；Tel: 0459-6819001; 0459-6819170

摘　要：

以抗旱性强的‘郑单958’和抗旱性弱的‘吉单522’为材料, 采用聚乙二醇(PEG-6000)模拟水分胁迫方法, 研究了水分胁迫及复水对不同抗性玉米苗期相关生理特性的影响。结果表明, 在水分胁迫及复水条件下, ‘郑单958’和‘吉单522’的叶片净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、胞间CO₂浓度(C_i)、叶绿素含量和相对含水量(RWC)均呈先下降后上升趋势, 除‘吉单522’的C_i和叶绿素含量分别在胁迫后2 d和复水后1 d达到最低值外, 其余各指标均在胁迫后3 d达到最低值, 且‘吉单522’下降幅度更大, 复水后恢复缓慢, 但是在胁迫过程中‘郑单958’和‘吉单522’的RWC差异不显著。相对电导率, 丙二醛(MDA)含量, 超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性, 可溶性糖、可溶性蛋白、脯氨酸含量在水分胁迫及复水条件下呈先升高后下降趋势, 并在胁迫后3 d达到最大值, 其中‘吉单522’的相对电导率和MDA含量上升幅度大于‘郑单958’, 其余各指标‘郑单958’的增加幅度均高于‘吉单522’。‘郑单958’在水分胁迫时受到的伤害程度要小于‘吉单522’, 在复水过程中‘郑单958’具有良好的恢复能力。

关键词：玉米; 水分胁迫; 复水; 生理特性

收稿：2015-01-23   修定：2015-04-27

资助：“十二五”农村领域国家科技计划课题(2013BAD07B01-07), 第三、四积温带玉米新品种选育及高产技术示范(GA12B101-03), 黑龙江省农垦总局重点科技示范推广项目(HNK125TG-03)。

Effects of Water Stress and Subsequent Rehydration on Physiological Characteristics of Maize (Zea mays) with Different Drought Tolerance

LIU Cheng, LI Zuo-Tong^*, YANG Ke-Jun^*, XU Jing-Yu, WANG Yu-Feng, ZHAO Chang-Jiang, ZHANG Yi-Fei, LI Zhu, SUN Shao-Hui, FU Shi-Jiang, ZHAO Ying, GU Ying-Nan, FU Jian, FANG Yong-Jiang, LIU Yu, ZHANG Fa-Ming, MA Li-Feng, SHI Xin-Xin

Key Laboratory of Crop Germplasm Improvement and Cultivation in Cold Regions, College of Agronomy, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang 163319, China

Corresponding author: LI Zuo-Tong; E-mail: lxg6401999@163.com, byndykj@163.com; Tel: 0459-6819001; 0459-6819170

Abstract:

Two maize (Zea mays) varieties, ‘Zhengdan 958’ (drought-tolerant) and ‘Jidan 522’ (drought-sensitive) were used as experimental materials, and polyethylene glycol (PEG-6000) was used to simulate the water stress condition to investigate the effects of water stress and subsequent rehydration on physiological characteristics of maize varieties with different drought tolerance. The results showed under water stress condition, both varieties exhibited a declining trend on net photosynthetic rate (P_n), stomatal conductance (G_s), transpiration rate (T_r), intercellular CO₂ concentration (C_i), chlorophyll content and relative water content (RWC), then all above mentioned parameters demonstrated an increasing trend during the subsequent rehydration process; all parameters reached the lowest level on the third day after dehydration except the C_i and chlorophyll content of ‘Jidan 522’, which reached the lowest level on the second day after dehydration and the first day after rehydration respectively; greater decline on all the parameters were observed for ‘Jidan 522’ when stressed/dehydrated, which also experienced a slower recovery after rehydration, but the differences of RWC between ‘Zhengdan 958’ and ‘Jidan 522’ were not significant under stress. For both varieties, the relative electric conductivity, malondialdehyde (MDA) content, the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), soluble sugar content, soluble protein content and proline content also followed a first-increase-then-decrease pattern, and reached the highest level on the third day after dehydration; a greater increase in the relative electric conductivity and MDA content were observed for ‘Jidan 522’ over ‘Zhengdan 958’, while ‘Zhengdan 958’ exhibited a greater increase for all other parameters. All the results showed that less damage was made to ‘Zhengdan 958’ than ‘Jidan 522’ under water stress, and ‘Zhengdan 958’ also showed better recovery ability in the process of subsequent rehydration.

Key words: maize; water stress; rehydration; physiological characteristics