《植物生理学报》 2015, 51(5): 737-746

冬季低温胁迫对油菜抗寒生理特性的影响

张晓红, 冯梁杰, 杨特武, 徐正华, 胡立勇^*

华中农业大学植物科学技术学院, 农业部长江中游作物生理生态与耕作重点实验室, 武汉430070

通信作者：胡立勇；E-mail: liyonghu@mail.hzau.edu.cn；Tel: 027-87281393

摘　要：

以4个甘蓝型油菜品种为试验材料, 在大田栽培条件下研究冬季自然低温对油菜功能叶脯氨酸、可溶性糖(SS)、可溶性蛋白(SP)、丙二醛(MDA)含量以及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)酶活性的影响。结果表明, 日均温降至5 ℃以下, 多数生理指标出现升高或降低现象, 至3 ℃以下开始表现一定的生理性伤害, 0 ℃以下则伤害加重。不同生理指标对低温的反应有不同, 随着日均温降低至5 ℃以下, 脯氨酸和可溶性糖含量上升, 二者均在日均温降至0 ℃以下时达到最大值; 而CAT活性在日均温降至5 ℃左右时明显升高并出现最大值, SOD活性则在3 ℃左右达到最高; SP、MDA含量在日均温降至10、5和0 ℃时呈先下降后上升的趋势。不同生理指标比较, 以功能叶可溶性糖含量随环境温度下降而迅速升高的反应最明显; 脯氨酸含量、SOD和CAT酶活性等指标能相对稳定地反应不同品种的抗寒性差异。根据不同品种在低温下的农艺性状表现及田间冻害指数, 结合生理指标变化差异, 认为4个品种中抗寒性相对较强的为‘华双5号’。

关键词：甘蓝型油菜; 低温胁迫; 冻害指数; 渗透调节物质; 抗氧化酶

收稿：2015-02-04   修定：2015-04-13

资助：国家科技支撑计划(2010BAD01B01)和国家自然科学基金青年基金(4004-34113030)。

Effects of Chilling Stress on Physiological Characteristics of Rapeseed Seedlings in Winter

ZHANG Xiao-Hong, FENG Liang-Jie, YANG Te-Wu, XU Zheng-Hua, HU Li-Yong^*

Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River of Agriculture Ministry, College of Plant Science and Technology of Huazhong Agricultural University, Wuhan 430070, China

Corresponding author: HU Li-Yong; E-mail: liyonghu@mail.hzau.edu.cn; Tel: 027-87281393

Abstract:

Four cultivars of rapeseed (Brassica napus L.) were used to determine the changes in proline, soluble sugar, soluble protein, malondialdehyde (MDA) contents and superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) activities of functional leaf under natural chilling stress in a field experiment. The results showed that most physiological indicators changed obviously in leaves when mean daily temperature decreased below 5 ℃ and physiological injury occurred when temperature was below 3 ℃, the injury became worse when temperature was below 0 ℃. Various physiological indicators showed different responses to low temperature in leaves. The contents of proline and soluble sugar increased when mean daily temperature decreased to 5 ℃ and reached the maximum when temperature was below 0 ℃. Nevertheless, CAT and SOD activity reached the highest when temperature dropped to 5 ℃, and 3 ℃, respectively. The contents of soluble protein and MDA showed a trend to decrease at first and then increase when mean daily temperature dropped to 10 ℃, 5 ℃ and 0 ℃. Amongst the physiological indicators, soluble sugar content was most sensitive to low temperature in functional leaves; proline content and SOD and CAT activity could relatively steadily reflect the cold tolerance of different cultivars. Combined the injury index and agronomic performances with physiological changes under low temperature of cultivars, ‘Huashuang 5’ showed highest tolerance to cold stress.

Key words: Brassica napus; chilling stress; freezing index; osmolyte; antioxidase