中国农业科学 ›› 2019, Vol. 52 ›› Issue (21): 3782-3793.doi: 10.3864/j.issn.0578-1752.2019.21.007

• 专题:玉豆带状复合种植系统对光水的响应 • 上一篇    下一篇

玉米荫蔽对大豆光合特性与叶脉、气孔特征的影响

李盛蓝,谭婷婷,范元芳,杨文钰(),杨峰()   

  1. 四川农业大学农学院/农业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
  • 收稿日期:2019-08-04 接受日期:2019-09-19 出版日期:2019-11-01 发布日期:2019-11-12
  • 通讯作者: 杨文钰,杨峰
  • 作者简介:李盛蓝,E-mail: 1486376937@qq.com
  • 基金资助:
    国家重点研发计划(2016YFD0300209)

Effects of Maize Shading on Photosynthetic Characteristics, Vein and Stomatal Characteristics of Soybean

LI ShengLan,TAN TingTing,FAN YuanFang,YANG WenYu(),YANG Feng()   

  1. College of Agronomy, Sichuan Agricultural University/Key Laboratory of Crop Ecophysiology and Farming System in Southwest China, Ministry of Agriculture/Sichuan Engineering Research Center for Crop Strip Intercropping System, Chengdu 611130
  • Received:2019-08-04 Accepted:2019-09-19 Online:2019-11-01 Published:2019-11-12
  • Contact: WenYu YANG,Feng YANG

摘要:

目的 探究在玉米-大豆套作模式下,玉米大豆共生期内玉米荫蔽对大豆光合特性及叶脉、气孔特征的影响。方法 在自然光照射下采用两因素完全随机盆栽试验,以强耐荫性品种南豆12和弱耐荫性品种桂夏3号为研究对象,设置T1(2行玉米间隔2行大豆套作)、T2(1行玉米间隔1行大豆套作)和CK(净作大豆)3种空间配置,探究不同处理下大豆光合参数、叶脉和气孔特征参数对光环境的响应。结果 与净作相比,玉米荫蔽下大豆冠层的远红光光谱辐照度显著增加,T1、T2处理下的光照强度分别降低48.62%和77.39%。在玉米荫蔽下大豆的净光合速率、气孔导度、叶脉密度和气孔密度显著低于CK(P<0.05),且下降幅度都随着荫蔽程度的增加而增加(由T1到T2处理)。与CK相比,T1、T2处理下南豆12的净光合速率分别显著下降41.00%、44.15%,桂夏3号的净光合速率分别显著下降44.62%、47.93%;南豆12的气孔导度分别显著下降29.19%、39.69%,桂夏3号的气孔导度分别显著下降26.83%、49.50%。同时,南豆12的叶脉密度在T1、T2处理下分别比CK显著下降14.99%、20.01%,气孔密度分别下降12.79%、18.27%;桂夏3号的叶脉密度在T1、T2处理下分别比CK显著下降10.38%、27.62%,气孔密度分别下降15.77%、22.46%。此外,大豆的净光合速率与气孔导度、叶脉闭合度、气孔密度、叶脉密度呈显著正相关关系(P<0.05),与叶脉间距呈极显著负相关关系(P<0.01);叶脉密度与气孔密度呈极显著正相关关系(P<0.01)。玉米荫蔽下,南豆12的叶脉密度、叶脉长度、叶脉闭合度、叶脉间距都显著优于桂夏3号。在荫蔽程度更高的T2处理下,除蒸腾速率和叶脉闭合度以外,强耐荫性品种南豆12的光合、叶脉和气孔各参数的变化幅度都小于桂夏3号,且净光合速率更高。结论 在玉米-大豆套作的种植模式中,大豆冠层光环境、叶脉和气孔特征的变化会影响大豆的光合能力,但不同耐荫性大豆品种的叶脉、气孔特征对荫蔽的响应存在差异。

关键词: 套作, 大豆, 光合特性, 叶脉, 气孔

Abstract:

【Objective】 The aim of this study was to explore the effects of maize shading on the photosynthetic characteristics, leaf veins and stomatal characteristics of soybean during the symbiosis period under the maize-soybean intercropping system. 【Method】 Two factors were used in a completely randomized pot experiment under natural light, strong shade tolerant Nandou 12 and light shade tolerant Guixia 3, including the T1 (intercropping of 2 rows of maize and 2 rows of soybean), T2 (intercropping of 1 row of maize and 1 row of soybean) and CK (net for soybean) three treatments, respectively, to analyze photosynthetic parameters, veins and the porosity characteristic parameters’ responding under shading. 【Result】 By contrast with the net treatment, the far-red spectral irradiance of soybean canopy increased significantly under the shade of maize, and the light intensity under T1 and T2 treatment decreased by 48.62% and 77.39%, respectively. Photosynthetic rate, stomatal conductance, leaf vein density and stomatal density of soybean under maize shading were significantly less than those under CK (P<0.05), and the decrease rate increased with the increase of shade (from T1 to T2). Compared with CK, the net photosynthetic rate of Nandou 12 decreased significantly by 41.00% and 44.15% respectively under T1 and T2 treatment, the net photosynthetic rate of Guixia 3 decreased significantly by 44.62% and 47.93%, respectively, while stomatal conductance of Nandou 12 decreased significantly by 29.19% and 39.69%, and that of Guixia 3 decreased significantly by 26.83% and 49.50%, respectively. The vein density and stomatal density of Nandou 12 decreased by 14.99%, 20.01% and stomatal density decreased by 12.79%, 18.27% respectively under T1 and T2 treatment compared with CK; The vein density and stomatal density of Guixia 3 decreased by 10.38%, 27.62% and stomatal density decreased by 15.77%, 22.46% respectively under T1 and T2 treatment compared with CK. The net photosynthetic rate of soybean had significant positive correlation (P<0.05) with stomatal conductance, vein closure, stomatal density as well as vein density, and extremely negative correlation (P<0.01) with vein distance. In addition, there was an extremely significant positive correlation (P<0.01) between vein density and stomatal density. The vein density, vein length, veins closure, and the distance between the veins of Nandou 12 under maize shading were better than those of Guixia 3. In addition, the shade degree under T1 treatment was higher, while transpiration rate and vein closure, photosynthetic, vein and stomatal parameters of strong shade tolerant Nandou12 all change were less than those of Guixai 3, and Nandou had higher photosynthetic rate.【Conclusion】 In the maize-soybean intercropping system, the changes of canopy light environment, leaf vein and stomatal characteristics of soybean could reduce the photosynthetic ability of soybean, but the response of leaf vein and stomatal characteristics of different shade-tolerant soybean varieties to shading was different.

Key words: intercropping, soybean, photosynthetic characteristics, veins, stomatal