间作套种对培肥地力、提高粮食播种面积和产量、促进种植业可持续发展具有重要作用。但在玉米大豆间套作过程中，玉米遮荫导致大豆茎秆强度低，倒伏严重，而前期研究发现套作大豆茎秆强度和抗倒性与茎秆中的木质素含量密切相关，但荫蔽对木质素代谢的作用机理尚不清楚。本项目将以茎秆强度和倒伏率不同的大豆为材料，室内与大田试验相结合，将植物生理学和分子生物学的方法和技术应用到作物栽培学，对荫蔽环境下不同基因型大豆木质素积累过程、木质素代谢途径的苯丙烷类中间产物、关键酶活性进行分析，找到荫蔽对大豆木质素代谢影响的关键环节；将转录组测序数据与定量PCR验证、蛋白印迹相结合，获得与木质素代谢相关的套作大豆抗倒功能基因；将上述关键环节和功能基因表达相结合，研究其对不同光环境的响应规律，最终揭示荫蔽环境对不同茎秆强度大豆木质素代谢的作用机理，为套作大豆抗倒调控技术研发和品种筛选、减少田间倒伏、提高产量奠定理论基础。

Intercropping plays an important role to enhance soil fertility, increase crop production, and promote sustainable developments of agricultural. But in maize and soybean intercropping system, shading results in lower soybean stem strength and severe lodging. The previous studies found that stem strength and lodging resistance of intercropping soybean were closely related to lignin contents. But the effect mechanism of shade on lignin metabolism is indistinct. Soybean cultivars with different stem strength and lodging resistance will be used in laboratory and field experiments. The methods and techniques for crop cultivation will be based on plant physiology and molecular biology, to investigate the stem lignin accumulation process, lignin metabolic pathways on intermediate phenylpropanes and main enzyme activity of different soybean genotypes under shade, to find the main factor of affecting stem lignin metabolic process of soybean. The transcriptome sequencing and quantitative data verification is combined with PCR and western blot to get the functional genes associated with lignin metabolism which resist lodging of soybean under intercropping, and to investigation the key sites of the study in response to gene expression under different light conditions. Finally reveals the mechanism of lignin metabolism on stem strength of soybean for lodging under different shade environment, this technology will lay the theoretical foundation for research development and screening of lodging resistant soybean varieties to reduce field lodging and increase yield.