Possibility of yield enlargement with raise of nodulation function in soybean

• Project/Area Number: 10660015
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 作物学
• Research Institution: Tottori University
• Principal Investigator: NAKANO Junichi Faculty of Agriculture, Tottori University, Associate Professor, 農学部, 助教授 (20032641)
• Project Period (FY): 1998 – 1999
• Project Status: Completed (Fiscal Year 1999)
• Budget Amount: ¥3,500,000 (Direct Cost: ¥3,500,000); Fiscal Year 1999: ¥400,000 (Direct Cost: ¥400,000); Fiscal Year 1998: ¥3,100,000 (Direct Cost: ¥3,100,000)
• Keywords: soybean / nodule / super-nodulation / grain yield / nodule activity / contribution rate / 根粒超着生系 / 窒素吸収量 / 相対ウレイド法

Research Abstract

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.