油菜幼苗光合及叶绿素荧光参数对干旱胁迫的响应及其抗旱性分析  

Photosynthetic and Chlorophyll Fluorescence Responses of Rape Seedlings to Drought Stress and Its Drought Resistance Evaluation

作　　者：庞进平[1] 王永生 PANG Jinping;WANG Yongsheng(Institute of Crop Sciences,Gansu Academy of Agricultural Sciences,Lanzhou 730070,China;Minle County Agricultural Technology Extension Center,Zhangye,Gansu 734000,China)

机构地区：[1]甘肃省农业科学院作物研究所,兰州730070 [2]甘肃省张掖市民乐县农技推广中心,甘肃张掖734000

出　　处：《西北植物学报》2023年第2期276-284,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：甘肃省科技重大专项(17ZD2NA016-4)。

摘　　要：该研究在人工控制水分条件下,设置3个干旱胁迫处理,选用3个主栽油菜品种‘陇油10号’、‘陇油2号’、‘青杂5号’幼苗进行盆栽试验,测定干旱胁迫条件下叶片相对含水量、叶绿素含量、光合气体交换参数及叶绿素荧光参数等指标,考察各指标在干旱胁迫过程中的变化特征,并通过主成分分析(PCA)和隶属函数法评价品种的抗旱性及其主要响应因子,以揭示西北地区油菜幼苗响应干旱胁迫的光合调控机制。结果表明:(1)各品种油菜幼苗的叶片相对含水量(RWC)均随干旱胁迫程度的递增而逐渐降低,最大水分亏缺(WSD)却逐渐上升。(2)各品种油菜幼苗叶片的叶绿素a含量、叶绿素总含量随着干旱胁迫程度的递增而先增加后递减,且同一种幼苗在不同处理间差异显著。(3)各品种油菜幼苗叶片的净光合速率(P_(n))、水分利用效率(WUE)、单株生物量、气孔导度(G_(s))、胞间CO_(2)浓度(C_(i))均在受到干旱胁迫时迅速降低,且同一品种幼苗在不同处理间差异显著,而其叶片蒸腾速率(Tr)在干旱胁迫下无显著变化。(4)各品种油菜幼苗叶片光化学猝灭系数(qP)和非光化学猝灭系数(NPQ)随着干旱胁迫程度的递增先增加后递减,最大光化学效率(F_(v)/F_(m))和电子传递速率(ETR)在受到干旱胁迫时迅速降低,且同一品种幼苗在不同处理间差异显著。(5)主成分分析结果表明,在油菜幼苗受到干旱胁迫时RWC、C_(i)、G_(s)、P_(n)、WUE、叶绿素总含量、叶绿素a含量和NPQ起主要调控作用;隶属函数法综合评价表明,3个品种油菜幼苗耐旱能力由高到低依次为‘陇油10号’>‘陇油2号’>‘青杂5号’。In this study,three drought stress treatments were set under artificial water control.We selected three main rapeseed varieties(‘Longyou No.10’,‘Longyou No.2’and‘Qingza No.5’)with pot experiment to measure the relative water content,chlorophyll content,photosynthetic gas exchange parameters and chlorophyll fluorescence parameters of leaves under drought stress.Principal component analysis(PCA)and membership function method were used to evaluate the drought resistance and its main response factors,and to explore the photosynthetic regulation mechanism of rapeseed seedlings in northwest China in response to drought stress.The results showed that:(1)the relative water content(RWC)in the leaves of all variety rapeseed seedlings decreased gradually with the increase of drought stress,while the maximum water deficit(WSD)increased gradually.(2)The chlorophyll a and total chlorophyll(a+b)contents in the leaves of all variety rapeseed seedlings first increased and then decreased with the increase of drought stress,and the same seedlings had significant differences among different treatments.(3)The net photosynthetic rate(Pn),water use efficiency(WUE),biomass per plant,stomatal conductance(G_(s))and intercellular CO_(2)concentration(C_(i))in the leaves of all variety rapeseed seedlings decreased rapidly under drought stress,and there were significant differences among different treatments of the same seedlings,while the transpiration rate(Tr)of the leaves did not change significantly under drought stress;(4)The photochemical quenching coefficient(qP)and non-photochemical quenching coefficient(NPQ)first increased and then decreased with the increasing degree of drought stress,and the maximum photochemical efficiency(F_(v)/F_(m))and electron transfer rate(ETR)rapidly decreased under drought stress,and the same seedlings had significant differences among different treatments.(5)The results of principal component analysis showed that RWC,C_(i),G_(s),P_(n),WUE,chlorophyll a,total chlorophyll,and NPQ played the main

关 键 词：油菜幼苗 干旱胁迫:光合气体交换参数 叶绿素荧光参数 抗旱性评价 

分 类 号：Q945.79[生物学—植物学] S565.4[农业科学—作物学]