荫蔽信号对大豆幼苗生长和光合特性的影响  

Effect of shading signal on growth and photosynthetic characteristics of soybean seedlings

作　　者：任梦露 刘卫国[1] 刘小明[1] 方萍[1] 杨文钰[1] 

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

出　　处：《中国生态农业学报》2016年第4期499-505,共7页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(31201170);四川省科技厅育种攻关项目(2011NZ0098-4)资助~~

摘　　要：红光/远红光比值(R/FR)下降是自然界荫蔽发生的重要信号。为探究大豆幼苗对荫蔽信号的应答机制,本文采用室内盆栽试验,以‘南豆12’和‘南032-4’两个大豆品种幼苗为材料,通过正常光照和低R/FR两种光照处理后,对其形态、光合特性以及叶绿素荧光参数进行研究。结果表明:与正常光照相比,低R/FR下,两个大豆材料幼苗均表现出典型的避荫性反应,即株高、叶面积、叶柄长、节间长增加,茎秆变细,其中,‘南豆12’的株高、叶柄长、节间长分别显著增加7.86%、81.48%、26.55%,‘南032-4’分别增加3.95%、76.67%、20.00%;叶片的光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)提高,胞间二氧化碳浓度(Ci)和初始荧光强度(Fo)、最大荧光(Fm)、最大光化学效率(Fv/Fm)、PSⅡ实际光化学效率(ΦPSⅡ)、光化学淬灭系数(q P)等降低,非光化学淬灭系数(q N)升高,总干物质积累量增加,其中,‘南豆12’和‘南032-4’的Pn分别增加37.21%和39.04%、总干物质积累量分别增加12.35%和17.36%、Ci分别降低9.29%和11.72%。然而,不同大豆材料对低R/FR的敏感程度不同。在低R/FR光环境下,‘南豆12’较‘南032-4’表现出较低的株高、节间长、叶柄长,较大的叶面积和茎粗,较高的光能传递转换效率、Pn、Gs以及干物质积累量,体现了对荫蔽较强的适应性。本研究进一步证实了大豆具有感受荫蔽信号(低R/FR)的能力,但其敏感程度因品种不同而不同,在间套作过程中,为提高大豆耐荫性,降低大豆因避荫反应导致的倒伏率,保障大豆产量,应该选择对荫蔽信号不敏感的品种。The reduction in the ratio of red light（R） to far-red light（FR） is an important signal of shade stress in nature. The objective of this study was to investigate the response mechanism of soybean seedlings to low R/FR signals. To this end, a pot culture experiment was conducted to study the effect of normal and low R/FR light irradiation on the morphology, photosynthetic characteristics and chlorophyll fluorescence of two soybean varieties（Glycine max L.） seedlings — ‘Nandou12 ‘and ‘Nan032-4＇. The results indicated that compared with seedlings under normal light, low-R/FR light increased soybean plant height, leaf area, petiole length and internode length, but reduced stem diameter. Plant height, petiole length and internode length of ‘Nandou12＇ increased by 7.86%, 81.48% and 26.55%, and that of ‘Nan032-4＇ increased by 3.95%, 76.67% and 20.00%, respectively, compared with the corresponding normal light treatment. Also compared with seedlings under normal light, leaf photosynthetic rate（Pn）, transpiration rate（Tr）, stomatal conductance（Gs） and photochemical quenching coefficient（q N） of seedlings under low R/FR treatment increased. However, intercellular CO2 concentration（Ci）, initial fluorescence intensity（Fo）, maximum fluorescence（Fm）, maximum photochemical efficiency（Fv/Fm）, actual PSⅡ photochemical efficiency（ΦPSⅡ） and light chemical quenching coefficient（q P） decreased under low R/FR treatment. Meanwhile, low-R/FR increased dry matter accumulation. Under low R/FR treatment, Pn and dry matter accumulation of ‘Nandou12＇ increased by 37.21% and 12.35% and those of ‘Nan032-4＇ increased by 39.04% and 17.36%, respectively. Compared with seedlings under normal light treatment, Ci of ‘Nandou12＇ and ‘Nan032-4＇ decreased by 9.29% and 11.72%, respectively. However, different soybean varieties had different degrees of response to low-R/FR. Under low-R/FR light condition, the plant height, internode length and petiole length of ‘Na

关 键 词：大豆 荫蔽信号 红光/远红光比值(R/FR) 光合作用 叶绿素荧光 

分 类 号：S565.101[农业科学—作物学]