欢迎访问《生态学杂志》官方网站,今天是 分享到:

生态学杂志 ›› 2020, Vol. 39 ›› Issue (12): 4048-4056.doi: 10.13292/j.1000-4890.202012.003

• 研究报告 • 上一篇    下一篇

低温胁迫后红树植物秋茄幼苗光合特性及蔗糖代谢的恢复机制

郑春芳1*,陈威2,刘伟成3,王海东4,万寒4,陈继浓3,仇建标3   

  1. 1城镇水污染生态治理技术国家地方联合工程研究中心, 温州大学生命与环境科学学院, 浙江温州 325035;2平阳县自然资源和规划局, 浙江温州 325400; 3浙江省海洋水产养殖研究所, 浙江温州 325005;4温州市气象局, 浙江温州 325000)
  • 出版日期:2020-12-10 发布日期:2021-06-10

Recovery mechanisms of photosynthesis and sucrose metabolism in Kandelia obovata seedlings from low temperature stress.

ZHENG Chun-fang1*, CHEN Wei2, LIU Wei-cheng3, WANG Hai-dong4, WAN Han4, CHEN Ji-nong3, QIU Jian-biao3   

  1. (1National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, College of Life and Environmental Science, Wenzhou University, Wenzhou 325035, Zhejiang, China; 2Pingyang Bureau of Natural Resources and Planning, Wenzhou 325400, Zhejiang, China; 3Zhejiang Key Laboratory of Exploitation and Preservation of Coastal Bioresource, Zhejiang Mariculture Research Institute, Wenzhou 325005, Zhejiang, China; 4Wenzhou Meteorological Bureau, Wenzhou 325000, Zhejiang, China).
  • Online:2020-12-10 Published:2021-06-10

摘要: 为明确低温胁迫后红树植物光合恢复机制,以3种伤害程度的秋茄(Kandelia obovata)幼苗为材料,研究低温胁迫后秋茄幼苗叶片冷害指数(CII)、光合荧光参数、叶绿素含量、抗氧化酶活性以及蔗糖代谢等变化特征。结果表明,随着低温胁迫伤害程度的增大,植株幼苗叶片净光合速率(Pn)、气孔导度(Gs)、叶绿素含量(CHL)、叶绿素a/b(Chla/Chl/b)值、PSII最大光化学效率(Fv/Fm)、实际光化学效率(ΦPSII)、光化学淬灭系数(qP)以及APX活性均逐渐降低,而CII、非光化学猝灭系数(NPQ)、相对电导率(REC)和丙二醛(MDA)含量均逐渐增加。另外,植株幼苗叶片蔗糖合成酶SS)、蔗糖磷酸合成酶(SPS)活性和可溶性总糖(TSS)、蔗糖含量却随着伤害程度加大而先增后降。低温胁迫后恢复15天,轻度伤害(LLS)和中度冻害(MLS)的植株均未出现明显伤害症状,而严重冻害(SLS)的植株大部分叶片出现叶焦、芽枯现象。低温胁迫恢复3天后,LLS和MLS植株均能通过改善自身抗氧化系统和蔗糖代谢,减轻叶片PSII光抑制的伤害,减缓光合能力下降,而SLS植株因低温伤害严重而导致光合生理功能短期内无法恢复。下列生理指标可以用于评价低温胁迫后红树植物恢复能力的强弱:PnGsFv/FmФPSIIqPNPQ、Chla/Chlb、MDA、APX、POD、REC。

关键词: 低温胁迫, 秋茄, 光合作用, 叶绿素荧光, 蔗糖合成

Abstract: To clarify the mechanisms of photosynthetic recovery in mangrove from low temperature stress, we examined the changes of chilling injury index (CII), leaf photosynthetic and chlorophyll fluorescence parameters, chlorophyll content, antioxidant enzyme activity, and sucrose metabolis in Kandelia obovata seedlings with three levels of lowtemperature injury. The results showed that leaf net photosynthetic rate (Pn), stomatal conductance (Gs), chlorophyll content (CHL), chlorophyll a/chlorophyll b (Chla/Chlb) ratio, photochemical efficiency of photosystem II (Fv/Fm), actual photochemical efficiency (ΦPSII), photochemical quenching coefficient (qP) and APX activity of seedlings gradually decreased with the increasing degree of injury, whereas CII, leaf non-photochemical quenching (NPQ), relative electrical conductivity (REC), and malondialdehyde (MDA) content gradually increased. The activities of sucrose synthase (SS) and sucrose phosphate synthase, and TSS and sucrose contents increased initially and then decreased with the increasing degree of injury. Seedlings under both light low-temperature stress (LLS) and moderate low-temperature stress (MLS) treatments showed no obvious injury symptoms in 15 days after low temperature stress, while seedlings of severe low-temperature stress (SLS) showed leaf scorch and bud withering.  LLS and MLS treatments may alleviate the decline of photosynthetic capacity in leaves by effectively improving defensive system of antioxidants and sucrose metabolism and reducing the damage of photoinhibition of PSII for three days recovery after low temperature stress, while the photosynthetic function of seedlings of SLS could not be recovered from severe damage of low temperature stress in short term. The following indices could be used to evaluate the recovery ability of mangrove plant after low temperature stress, including Pn, Gs, Fv/Fm,ФPSII, qP,NPQ, Chla/Chlb, MDA, APX, POD and REC.

Key words: low temperature stress Kandelia obovata, photosynthesis, chlorophyll fluorescence, sucrose synthesis.