大豆豆荚光合特性及其对产量的贡献

Photosynthetic characteristics of soybean pod and its contribution to yield

以大豆东农42、东农163为试验材料，对不同生育期豆荚和叶片的光合速率、蒸腾速率、水分利用效率、气孔导度、叶绿素含量、可溶性蛋白含量等生理指标进行了研究，并通过在鼓粒始期R5、鼓粒期凡、生理成熟期R7对豆荚进行遮光处理，研究豆荚对籽粒重的影响。结果表明，豆荚具有光合作用的能力，光合速率在生理成熟期R7最高；蒸腾速率、气孔导度随着生育期的延续呈下降趋势，而水分利用效率逐渐上升；整个测定生育期内，东农42、东农163豆荚叶绿素含量分别占其叶片的7．63％和7．25％，可溶性蛋白含量占其叶片的53．47％和48．82％；在鼓粒始期R5进行遮光处理表明，豆荚的光合产物对籽粒重的贡献率达到7．34％～15．06％。

Soybean cuhivars Dongnong 42 and Dongnong 163 were used as experimental material. Changes of photosynthetic rate, transpiration rate, water use efficiency, stomatal conductance, chlorophyll content, and soluble protein content at different growing stages in the pods and leaves of soybean cuhivars were studied. The effect of pods on seeds weight were also investigated by shading pods at R5, R6 and R7 growing stages. The results showed that soybean pod had photosynthetic ability and its photosynthetic rate reached the peak value at R7 stage. In the whole growing stages, the transpiration rate and stomatal conductance of pod decreased, but the water use efficiency increased. The average chlorophyll content of pods in Dongnong42 and Dongnong163 took up 7.63% and 7.25% of their respective leaves. The soluble protein content of pods in Dongnong42 and Dongnong163 took up 53.47% and 48.82% of their respective leaves. From R5 stage to harvest time, the contribution rate of the photosynthetic product of pods to seeds weight reached 7.34%-15.06%.