The effect of starting dose of nitrogen on the formation of root nodule and symbiotic system, and also on the activity of nitrogen fixation and nitric nutrition of soybean plant was studied. It is supposed that the use of small dose of nitrogen (25 mg N/plant) in the beginning of vegetation period, despite luck of mineral nitrogen in medium, on the beginning of flowering until seed ripening produces favourable conditions for the functioning of symbiotic system, thereby facilitates the normal formation of beans and total nitrogen reserves of plant.

Soybean, small doses of nitrogen, nitrogen fixation, total nitrogen

1. Aliev D.A., Akperov Z.I. Fotosintez i urozhaj soi. Moskva-Baku: IK "Rodnik", 1995.
2. Provarov N.A. Fiziologija rastenij. 1996. T. 43, № 3.
3. Rin'kis G.Ja. Optimizacija mineral'nogo pitanija rastenij. Riga. Znatne. 1972.
4. Chmelev Z.V., Tetjurev S.L. Metody belkovogo i aminokislotnogo analiza rastenij. Inst. Rastenievodstva im. N.I.Vavilova, 1973.
5. Gadimov A.G., Safaraliev P.M, Troitskaya G.N., Allahverdiev S.R., Nafisi S. Change in nitrogen status of soubean under influnce of symbiotically fixed and bound nitrogen. Tr. J. of Agriculture and forestry. v. 23, 1999.
6. Eaqlesham A.R.J., Hassoura S., Seegers R. Fertilizer N Effects on N2 Fixation by Cowpea and Soybean. Agron.J. 1983.v.75. N.1.
7. Hardi R.W.F., Havelka U.D. Symbiotic nitrogen fixation in plants. Ed. P.Nutman. L.: Cambridge Univ/press, 1975. (Intern. Biol. Program: ser. 7).
8. Oghogorie C.G.O., Pate J.S. The nitrate stress syndrome of the nodulated field pea (Pisum arvense L.)//Plant and Soil, Special vol., 1971.