《植物生理学报》 2016, 52(1): 109-116

烯效唑对低温胁迫下秋茄幼苗光合作用与抗氧化系统的影响

郑春芳¹, 陈继浓¹, 仇建标¹, 刘伟成^1,*, 张呈念², 彭欣¹

¹浙江省海洋水产养殖研究所, 温州海洋研究院, 浙江省近岸水域生物资源开发与保护重点实验室, 浙江温州325005; ²温州科技职业学院, 浙江温州325006

通信作者：刘伟成；E-mail: lzlzly2010@126.com

摘　要：

以秋茄(Kandelia obovata)幼苗为材料, 研究了喷洒0.1 mmol•L^-1烯效唑对植株叶片光合作用、叶绿素、荧光特性、抗氧化系统及细胞膜透性的影响。结果表明: 烯效唑能显著提高低温胁迫下秋茄幼苗叶片净光合速率(P_n)、气孔导度(G_s)、叶绿素含量和叶绿素a/叶绿素b (Chl a/Chl b)比值, 降低胞间CO₂浓度(C_i)和气孔限制值(L_s); 同时烯效唑也能显著提高低温胁迫下秋茄幼苗叶片PSII最大光化学效率(F_v/F_m)、实际光化学效率(Φ_PSII)、光化学猝灭系数(q_P), 增加了超氧化物歧化酶(SOD)、过氧化物酶(POD)与抗坏血酸过氧化物酶(APX)活性, 反而降低了非光化学猝灭系数(NPQ)、细胞膜透性和丙二醛(MDA)积累, 说明烯效唑处理能改善低温胁迫下秋茄植株抗氧化系统运行, 增强其植株光合电子传递效率, 从而有效促进植株的光合作用, 减少低温胁迫对秋茄叶片细胞的伤害。

关键词：红树林; 秋茄; 烯效唑; 低温胁迫; 光合作用; 抗氧化系统

收稿：2015-07-22   修定：2015-12-21

资助：海洋公益性行业科研专项经费项目(20150528)、浙江省重大科研专项(2012C12017-3)、浙江省自然科学基金(LQ13C030002)、浙江省科技计划项目(2013C25096和2014F50003)、浙江省远洋渔业(2015)“基于生态系统水平的中以(中国-以色列)海水养殖技术合作与交流”。

Effect of uniconazole on photosynthesis and antioxidant system in Kandelia obovata seedlings under low temperature stress

ZHENG Chun-Fang¹, CHEN Ji-Nong¹, QIU Jian-Biao¹, LIU Wei-Cheng^1,*, Zhang Cheng-Nian², Peng Xin¹

¹Zhejiang Key Laboratory of Exploitation and Preservation of Coastal Bio-resource, Wenzhou Ocean Research Institute, Zhejiang Mariculture Research Institute, Wenzhou, Zhejiang 325005, China; ²Wenzhou Vocational College of Scinece and Technology, Wenzhou, Zhejiang 325006, China

Corresponding author: LIU Wei-Cheng; E-mail: lzlzly2010@126.com

Abstract:

The effect of uniconazole on leaf photosynthetic characteristics, chlorophyll fluorescence and antioxidant system in Kandelia obovata seedling under cold stress was investigated. Kandelia obovata seedlings were pretreated with 0.1 mmol•L^-1 uniconazole for 7 d, and then exposed to cold stress at day/night of (5/−2)°C for 48 h. Results show that the net photosynthetic rate (P_n), stomatal conductance (G_s), chlorophyll content and Chl a/Chl b ratio significantly increased, and intercellular CO₂ concentration (C_i) and stomatatal limitation (L_s) were reduced in K. obovata leaves by the use of uniconazole. The photochemical efficiency of photosystem II (F_v/F_m), actual photochemical efficiency (Φ_PSII) and photochemical quenching cofficient (q_P) could be enhanced, but non-photochemical quenching coefficient (NPQ) decreased, in K. obovata leaves with uniconazole treatment. In addition, uniconazole alleviated the oxidative damage in leaves of K. obovata by reducing cell membrane permeability and lipid peroxidation, and by increasing the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POD). Sum up, it indicates that uniconazole alleviates freezing-induced cell damages through regulating the photosynthesis and antioxidant system of K. obovata.

Key words: mangrove; Kandelia obovata; uniconazole; low temperature stress; photosynthesis; antioxidant system