中国农业气象 ›› 2022, Vol. 43 ›› Issue (04): 285-294.doi: 10.3969/j.issn.1000-6362.2022.04.004

• 农业生物气象栏目 • 上一篇    下一篇

低温寡照条件下黄瓜叶片光合作用减弱的机理分析

张瑶,杨再强,姜雨函,苏泽阳,徐若涵,龙宇芸   

  1. 1.南京信息工程大学气象灾害预报预警与评估协同创新中心,南京 210044;2.江苏省农业气象重点实验室,南京 210044
  • 收稿日期:2021-07-17 出版日期:2022-04-20 发布日期:2022-04-18
  • 通讯作者: 杨再强,教授,博士生导师,主要研究设施环境调控,E-mail:yzq@nuist.edu.cn E-mail:yzq@nuist.edu.cn
  • 作者简介:张瑶,E-mail:20201208039@nuist.edu.cn
  • 基金资助:
    国家重点研究开发计划(2019YFD1002202)

Mechanism Analysis on Photosynthetic Attenuation in Cucumber Leaves under Low Temperature and Weak Light Condition

ZHANG Yao, YANG Zai-qiang, JIANG Yu-han, SU Ze-yang, XU Ruo-han,LONG Yu-yun   

  1. 1. Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; 2.Jiangsu Provincial Key Laboratory of Agrometeorology, Nanjing 210044
  • Received:2021-07-17 Online:2022-04-20 Published:2022-04-18

摘要: 以黄瓜品种‘津优101’(Jinyou101)为试材,于2020−2021年在南京信息工程大学利用人工气候箱开展低温寡照双因素环境控制试验。昼/夜温设置13℃/3℃、16℃/6℃、19℃/9℃、22℃/12℃共4个水平,光合有效辐射(PAR)设置200和400μmol·m−2·s−1两个水平,各处理均分别持续3、6、9、12d,以28℃/18℃和800μmol·m−2·s−1的光温设置为对照(CK)。测定不同处理下幼苗期黄瓜叶片的叶绿体色素含量、光合参数和快速叶绿素荧光诱导动力学参数,以探究低温寡照条件下黄瓜幼苗叶片光合作用减弱的机理。结果表明:(1)不同处理下黄瓜叶片的各叶绿体色素含量均随温度和PAR降低而降低,随处理时间延长而降低。(2)不同处理下叶片最大光合速率(Pmax)、光饱和点(LSP)、气孔导度(Gs)和蒸腾速率(Tr)均随胁迫程度和时间的增加呈降低趋势,光补偿点(LCP)随胁迫程度和时间的增加呈上升趋势,说明低温寡照胁迫程度越深、胁迫时间越长,黄瓜叶片光合作用越弱。(3)随着胁迫程度加深和时间延长,黄瓜叶片快速荧光诱导动力学曲线(OJIP曲线)的JIP相逐渐下降;能量分配比率参数(φPo、ψEo和φEo)均逐渐减小;单位活性反应中心所吸收(ABS/RC)和捕获(TRo/RC)的光能逐渐增加,但用于电子传递的光能(ETo/RC)仍逐渐减少。本研究证实,低温寡照处理使黄瓜叶片气孔导度下降,气体交换受阻;天线色素含量降低,叶片吸收和捕获的光能减少;PSII性能降低,用于光化学反应的能量减少,因而叶片光合作用减弱。

关键词: 黄瓜, 低温寡照, 光合作用, 快速荧光, OJIP曲线

Abstract: To study the mechanism of photosynthetic attenuation in cucumber seedling leaves under low temperature and weak light conditions, using cucumber variety 'Jinyou 101' as experimental material, a two-factor environmental control experiment of low temperature and weak light was carried out by using artificial climate boxes in Nanjing University of Information Science and Technology from 2020 to 2021. The daytime/night temperature was set at 13℃/3℃, 16℃/6℃, 19℃/9℃ and 12℃/22℃, and the photosynthetically active radiation (PAR) was set at 200, 400μmol·m−2·s−1. There were eight treatments, each of which lasted for 3, 6, 9 and 12 days, respectively. The treatment with light and temperature of 28℃/18℃ and 800μmol·m−2·s−1 was used as control (CK). The chloroplast pigment content, photosynthetic parameters, and kinetic parameters of rapid chlorophyll fluorescence induction in cucumber leaves at the seedling stage were measured under different treatments. The results showed that: (1) the chloroplast pigment content of cucumber leaves decreased with the decrease of temperature and PAR, and decreased with the prolongation of treatment time. (2) Under different treatments, the maximum photosynthetic rate (Pmax), light saturation point (LSP), stomatal conductance (Gs), and transpiration rate (Tr) decreased with the increase of stress degree and time, and the light compensation point (LCP) increased with the increase of stress degree and time. The results showed that the deeper the degree of low temperature and weak light stress and the longer the stress time, the weaker the photosynthesis of cucumber leaves. (3) With the deepening of stress and the prolongation of stress time, the JIP phase of the fast fluorescence induction kinetic curve (OJIP curve) of cucumber leaves decreased gradually, the parameters of energy distribution ratio (φPo, ψEo, and φEo) decreased gradually, and the light energy absorbed (ABS/RC) and trapped (TRo/RC) per unit active reaction center gradually increased, but the light energy used for electron transport (ETo/RC) still decreased. This study confirmed that low temperature and weak light treatment reduced the stomatal conductance of cucumber leaves and hindered gas exchange; the antenna pigment content decreased, and the light energy absorbed and captured by the leaves decreased; the performance of PSII decreased, and the energy used for photochemical reactions decreased; therefore, the photosynthesis of the leaves decreased.

Key words: Cucumber, Low temperature and weak light, Photosynthesis, Rapid fluorescence, OJIP curve