大豆群体冠层结构及光合特性的研究

采用北疆地区主栽春大豆品种，在适宜密度条件下于初荚期去叶疏荚改变粒叶比，探讨不同品种群体粒叶比与冠层结构和不同层次叶片的光合速率。结果表明：剪叶、疏荚处理后，叶面积指数(IAI)、消光系数降低，直射光透过率、散射光透过率增加，群体透光条件得到极大改善，其中IAI与群体消光系数之间呈极显著正相关(P=0．9966^**)，同时,去叶疏荚处理后，在结荚期和鼓粒初期群体光合速率下降。灌浆后期，去1／3叶和去1／2荚处理，群体光照条件改善，延缓了叶片的衰老，群体光合速率比对照增加，表明随着单位叶面积负荷量的增加，单位叶面积有效生产量随之增加，叶片光合生产潜力可以进一步发挥，光合产物有效性提高。

Studies on Character of Canopy and Photosynthesis in Soybean Population

To enhance canopy character and higher transmission coefficient for diffuse penetration and radiation penetration , higher leaf distribution and low coefficient extraction. The correlation between the leaf area index and coefficient extraction was very significant respectively ( R = 0. 9966 ) . By means of leaf-cutting and pod-thinning treatments, the CPA descent in podding period and early fulling, the community light shine onning the term improvement and defer the leaf's senile after removed 1/3 leafs and 1/2 pod,the CPA increased in filling period. It was clear that the photosynthetic potential could be fully played and the effectiveness of photosynthetic could be raised with the increase of unit-leaf-area load, which resulted in the rising of effective production per unit leaf area.