硅对人工荫蔽胁迫下大豆幼苗生长及光合特性的影响  

Effects of Silicon on Plant Growth and Photosynthetic Characteristics of Soybean Seedlings Under Artificial Shade Stress

作　　者：李淑贤 刘卫国[1] 高阳 刘婷[1] 周涛[1] 杜勇利 杨欢[1] 张浩[1] 刘俊豆 杨文钰[1] LI ShuXian;LIU WeiGuo;GAO Yang;LIU Ting;ZHOU Tao;DU YongLi;YANG Huan;ZHANG Hao;LIU JunDou;YANG WenYu(Institute of Ecological Agriculture,Sichuan Agricultural University/Key Laboratory of Crop Ecophysiology and Farming System in Southwest China,Ministry of Agriculture,Chengdu 611130;Sichuan Association of Agricultural Science Societies,Chengdu 610041)

机构地区：[1]四川农业大学生态农业研究所/农业部西南作物生理生态与耕作重点实验室,成都611130 [2]四川省农学会,成都610041

出　　处：《中国农业科学》2018年第19期3663-3672,共10页Scientia Agricultura Sinica

基　　金：国家自然科学基金(31671626)

摘　　要：【目的】本试验主要研究硅对荫蔽胁迫下大豆幼苗的生长及光合特性的影响,以期为间套作大豆培育壮苗提供参考。【方法】本研究于2017年在四川农业大学试验基地进行,以强耐荫性南豆12和弱耐荫性南032-42个大豆品种为材料,用黑色遮阳网(50%透光率)模拟玉米大豆套作的荫蔽环境条件,进行室外盆栽。试验设置4个处理,分别为CK(正常光照,喷蒸馏水);S0(50%荫蔽,喷蒸馏水);S1(50%荫蔽,喷施100 mg·kg^(-1) Na_2SiO_3·9H_2O水溶液);S2(50%荫蔽,喷施300 mg·kg^(-1 )Na_2SiO_3·9H_2O水溶液),在大豆苗期进行叶面喷施。测定大豆植株各部分的硅含量、叶片的光合参数和叶绿素含量,茎秆直径和抗折力、根系的形态特征和根冠比、干物质积累及可溶性糖含量等指标,分析硅对提高大豆苗期耐荫性的作用。【结果】苗期荫蔽导致2个大豆品种植株的总干物质积累量、各器官的硅含量和可溶性糖含量减少,同时,降低的指标还有茎粗、茎秆抗折力以及根长、根表面积、根体积和根冠比。荫蔽造成了大豆净光合速率(Pn)、气孔导度(Gs)及蒸腾速率(Tr)的降低,而胞间二氧化碳浓度(Ci)和叶绿素的含量增加。不同大豆品种对荫蔽环境的响应程度不同,与南032-4相比,南豆12在荫蔽环境下具有更高的光合能力(净光合速率、胞间二氧化碳浓度、蒸腾速率、气孔导度、叶绿素含量)、茎秆抗倒能力(茎粗、茎秆抗折力)及根系生长能力(根长、根表面积、根体积、根干重)。荫蔽环境下S1处理后,2个大豆品种的干物质积累量、可溶性糖含量和叶绿素含量增加,茎秆变粗,茎秆抗折力增强,根量增多,根面积和根体积变大;叶片的净光合速率、气孔导度和蒸腾速率升高,胞间二氧化碳浓度下降,最终幼苗变壮。不同耐荫性的大豆品种对不同浓度的硅敏感度不同,其中,在S2处理下,强耐荫性南豆12的净光合速率、叶片可溶性�【Objective】This experiment mainly studied the effects of silicon on the growth and photosynthetic characteristics of soybean seedlings under shade stress,in order to provide reference for cultivating strong seedlings of soybean intercropping.【Method】In 2017,in the experimental base of Sichuan Agricultural University,two soybean varieties Nandou12(strong shade-tolerance)and Nan 032-4(weak shade-tolerance)were used as experimental materials,and the black sun-shade net(50%light transmittance)was used to simulate the shade environment conditions of maize-soybean intercropping.The outdoor pot experiment was carried out,and 4 treatments were set up,including CK(Normal,spraying distilled water),S0(50%shade,spraying distilled water),S1(50%shade,spraying 100 mg·kg^-1 Na2SiO3·9H2O water solution),and S2(50%shade,spraying 300 mg·kg^-1 Na2SiO3·9H2O aqueous solution),spraying leaf surface of soybean at the seedling stage.The content of silicon,photosynthetic parameters,chlorophyll content,stem diameter and flexural strength of stem,root morphology and root/shoot ratio,dry matter accumulation,and soluble sugar content were measured.Finally,the effects of silicon on the shade tolerance of soybean seedlings were analyzed.【Result】The total dry matter accumulation of two soybean varieties,silicon content and soluble sugar content of each organ decreased.At the same time,stem diameter,stem resistance,as well as root length,root surface area,root volume and root/shoot ratio of root traits,were reduced.The sun-shade net reduced the radiation of sunlight to soybean,resulting in the decrease of net photosynthetic rate(Pn)and stomatal conductance(Gs)and transpiration rate(Tr)of soybean plants.While intercellular CO2 concentration(Ci)and chlorophyll content increased with the decrease of light.Soybean varieties with different shade tolerance had different degrees of response to the same shading environment.Nandou12 had strong adaptability under shade stress,therefore,which had higher photosynthetic capacity(net photosynth

关 键 词：硅 荫蔽胁迫 大豆 光合作用 耐荫性 

分 类 号：S565.1[农业科学—作物学]