Possibility of yield enlargement with raise of nodulation function in soybean

1. Nodule dry mass and nodule activity （measured as relative ureide method） decreased by heavy fertilization （more than N17g/m） in both varies， En6500（super nodulation strain） and Enrei（control）。Nodule dry mass of En6500 was four times as mach as weight of Enrei.2.Nodule weight and specific nodule activity （Nmg/g/Day） were reached the maximum value at early-maturing stage（R5）。En 6500的特定节点活动水平较低，约为Enrei的1/4。在重受精条件下，En 6500和Enrei的贡献率分别为58%和43%，适当地、可能地，在非受精条件下，两种变体的贡献率分别为67%和58%，尊重地。节点活动受到土壤硝基和土壤湿度的影响，但没有受到温度的影响很大。4.它并不清楚地包含超节点的特性并不具有优势性的特性，以适应yield enlargement。

1.Nodule dry mass and nodule activity (measured as relative ureide method) decreased by heavy fertilization (more than N17g/mィイD12ィエD1) in both varieties, En6500(super nodulation strain) and Enrei(control). Nodule dry mass of En6500 was four times as mach as weight of Enrei.2.Nodule weight and specific nodule activity (Nmg/g/day) were reached the maximum value at early- maturing stage(R5). Specific nodule activity of En6500 was low level, almost 1/4 of Enrei.3.In the heavy fertilization condition, the contribution rates of En6500 and Enrei were 58% and 43%, respectively, although, in the non-fertilization condition, the contribution rates of two varieties were 67% and 58%, respectively. Nodule activity was influenced by soil nitrogen and soil moisture, but was not affected very much by temperature.4.It is not concluded clearly that the characteristic of super-nodulation was not advantageous characteristic for yield enlargement.