光强对苗期大豆叶片水力导度及叶脉性状的影响  

Effect of Light Intensity on Leaf Hydraulic Conductivity and Vein Traits of Soybean at Seedling Stage

作　　者：高静 陈吉玉 谭先明 吴雨珊[1] 杨文钰[1] 杨峰[1] GAO Jing;CHEN JiYu;TAN XianMing;WU YuShan;YANG WenYu;YANG Feng(College of Agronomy,Sichuan Agricultural University/Key Laboratory of Crop Ecophysiology and Farming System in Southwest China,Ministry of Agriculture and Rural Affairs/Sichuan Engineering Research Center for Crop Strip Intercropping System,Chengdu 611130)

机构地区：[1]四川农业大学农学院/农业农村部西南作物生理生态与耕作重点实验室/四川省作物带状复合种植工程技术研究中心,成都611130

出　　处：《中国农业科学》2023年第22期4417-4427,共11页Scientia Agricultura Sinica

基　　金：国家重点研发计划(2022YFD2300902);国家自然科学基金(32071963)。

摘　　要：【目的】探究光强对苗期大豆叶片水力导度、光合特性和叶水势的影响,分析叶脉性状对不同生长光强的适应机制,为提高大豆光能利用提供理论支撑。【方法】选用强耐荫型的大豆品种南豆12和弱耐荫型的大豆品种桂夏7为试验材料,在人工气候室进行盆栽试验,设置高光强((424.47±12.32)µmol·m^(-2)·s^(-1),HL)、中光强((162.52±20.31)µmol·m^(-2)·s^(-1),ML)和低光强((93.93±9.87)µmol·m^(-2)·s^(-1),LL)处理。在处理20 d后研究不同生长光强对苗期大豆叶片水力导度、光合参数、叶片水势及叶脉性状的影响。【结果】相对于高光强处理,低光强处理下南豆12和桂夏7的叶片水力导度显著降低,南豆12的叶片水力导度在3个处理下均显著高于桂夏7。与高光强处理相比,在中、低光强处理下南豆12的叶片水力导度分别降低7.56%和21.24%,气孔导度分别降低43.96%和58.89%,净光合速率分别降低29.44%和46.49%。同样,桂夏7的叶片水力导度分别降低42.16%和23.71%,气孔导度分别降低54.55%和45.79%,净光合速率分别降低37.03%和42.06%。南豆12和桂夏7的叶片水势在处理间均无显著差异。大豆的叶片水力导度与气孔导度在3个光强处理下均达到极显著正相关(P<0.01),随着光强的降低,叶片水力导度与净光合速率呈显著正相关(P<0.05),与气孔导度呈极显著正相关(P<0.01)。对于叶脉结构,与高光强相比,中、低光强处理下两个大豆品种的小叶脉密度以及主叶脉和小叶脉的木质部导管面积均显著降低,且南豆12的小叶脉密度和主叶脉木质部导管面积在中、低光强处理下均显著高于桂夏7。南豆12的主叶脉密度在处理间无显著变化,桂夏7的主叶脉密度在中、低光强处理下较高光强显著降低11.4%和15.0%。光强降低显著增长了叶脉到气孔的距离。南豆12在中、低光强处理下叶脉到气孔的距离较高光强增长21.33%和60.01%,桂夏7叶脉到气�【Objective】The objective of this study is to explore the effects of light intensity on leaf hydraulic conductivity,photosynthetic traits,and water potential in soybean seedlings,analyze the adaptive mechanisms of leaf vein traits in response to varying light intensities,and to provide theoretical support for enhancing future light energy utilization in soybean.【Method】Two soybean varieties,Nandou 12(shade-tolerant)and Guixia 7(shade-sensitive),were cultivated and placed in growth chambers.The plants were exposed to varying light conditions,including high light intensity(HL)at(424.47±12.32)μmol·m^(-2)·s^(-1),medium light intensity(ML)at(162.52±20.31)μmol·m^(-2)·s^(-1),and low light intensity(LL)at(93.93±9.87)μmol·m^(-2)·s^(-1).After a 20-day treatment period,the impacts of different light intensities on hydraulic conductivity,photosynthetic parameters,leaf water potential,and leaf vein traits in the seedling leaves of soybean were examined.【Result】Compared with HL treatment,the leaf hydraulic conductivity of Nandou 12 and Guixia 7 under LL treatment was significantly decreased,and the leaf hydraulic conductivity of Nandou 12 under the three treatments was significantly higher than that of Guixia 7 under the three treatments.Compared with HL treatment,the leaf hydraulic conductivity of Nandu 12 under ML and LL treatments decreased by 7.56%and 21.24%,stomatal conductance decreased by 43.96%and 58.89%,and net photosynthetic rate decreased by 29.44%and 46.49%,respectively.Similarly,the leaf hydraulic conductivity of Guixia 7 under the ML and LL treatments decreased by 42.16%and 23.71%,stomatal conductance decreased by 54.55%and 45.79%,and net photosynthetic rate decreased by 37.03%and 42.06%,respectively.Additionally,no statistically significant differences were observed in the leaf water potential of both soybean varieties across the various treatments.Notably,leaf hydraulic conductivity and stomatal conductance of soybean exhibited a highly significant positive correlation(P<0.01)under the th

关 键 词：大豆 叶片水力导度 气孔导度 光强 叶脉 

分 类 号：S565.1[农业科学—作物学]