《植物生理学报》 2017, 53(3): 497-504

外源硫化氢对盐胁迫下茶树抗氧化特性的影响

黄菡, 郭莎莎, 陈良超, 肖斌^*

西北农林科技大学园艺学院, 陕西杨凌712100

通信作者：肖；E-mail: xiaobin2093@sohu.com

摘　要：

为了探讨盐胁迫下外源硫化氢(H₂S)对茶树抗氧化系统的调节作用, 本研究以茶树品种‘平阳特早’为试验材料, 通过不同浓度(0、0.05、0.1、0.5 mmol·L^-1) H₂S供体硫氢化钠(NaHS)喷施处理来测定盐胁迫下对茶树比叶重、根系活力、抗氧化酶活性、抗氧化剂含量和活性氧(ROS)积累特征及膜脂质过氧化水平的影响。结果显示: 100 mmol·L^-1 NaCl处理显著降低茶树比叶重、叶绿素含量和根系活力, 增加叶片电解质渗透率及过氧化氢(H₂O₂)、超氧阴离子(O₂ ¯· )和丙二醛(MDA)含量; 0.1 mmol·L^-1 NaHS喷施处理显著增强盐胁迫下茶树叶片抗氧化酶(SOD、POD、CAT、APX和GR)活性和非酶抗氧化剂(AsA和GSH)含量, 提高了叶片中游离脯氨酸(Pro)和可溶性蛋白含量, 却显著降低了叶片电解质渗透率及H₂O₂、O₂ ¯·和MDA的积累。以上结果说明, 外源H₂S能够提高盐胁迫下茶树的抗氧化水平, 降低ROS的积累, 保护细胞膜的完整性, 从而减轻盐胁迫引起的氧化损伤, 提高茶树对盐胁迫的适应能力, 并以0.1 mmol·L^-1 NaHS喷施处理效果最佳。

关键词：茶树; 硫化氢; 盐胁迫; 抗氧化能力

收稿：2016-12-08   修定：2017-03-06

资助：陕西省茶叶产业技术体系建设项目(K3330215131)和陕西省科技统筹重点难题招标项目(2013KTZB-02-01)。

Effects of exogenous hydrogen sulfide on the antioxidant characteristics of tea plant (Camellia sinensis) under salt stress

HUANG Han, GUO Sha-Sha, CHEN Liang-Chao, XIAO Bin^*

College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China

Corresponding author: XIAO Bin; E-mail: xiaobin2093@sohu.com

Abstract:

To evaluate the effects of exogenous hydrogen sulfide (H₂S) on the antioxidant characteristics of tea plant (Camellia sinensis) under salt stress, leaf mass per area (LMA), root activity, the activities of antioxidant enzymes, the level of antioxidants, reactive oxygen species (ROS) and lipid peroxidation of tea plant cv. ‘Pingyangtezao’ were determined by treatments with different concentrations of NaHS (0, 0.05, 0.1 and 0.5 mmol·L^-1), which is a donor of H₂S. The results showed that LMA, root activity and chlorophyll content were significantly declined, while electrolyte leakage and the accumulation of hydrogen peroxide (H₂O₂), superoxide (O₂ ¯· ) and malondialdehyde (MDA) were increased under the 100 mmol·L^-1 NaCl treatment. Under salt stress, the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX) and glutathione reductase (GR), the content of non-enzymatic compounds such as ascorbate (AsA) and glutathione (GSH), the accumulation of free proline (Pro) and soluble protein in the leaves were significantly enhanced, but electrolyte leakage and H₂O₂, O₂ ¯· and MDA contents were significantly decreased by treatment with 0.1 mmol·L^-1 NaHS. In summary, exogenous H₂S could improve the antioxidant capacity, reduce the accumulation of active oxygen, maintain membrane stability and redox homeostasis of tea plant under salt stress, thus reducing NaCl-induced oxidative stress and enhancing the adaptability of tea plant to salt stress. The optimum treatment concentration of NaHS was 0.1 mmol·L^-1.

Key words: tea plant; hydrogen sulfide; salt stress; antioxidant capacity