01322nam a2200145 a 450000100080000000500110000800800410001910000190006024501130007926002920019252006250048465000220110965000290113170000160116014573082026-03-23       2002    bl uuuu     u00u1 u    #d1 aANDRADE, D. S.  aMaximizing the contribution of biological nitrogen fixation in tropical legume crops.h[electronic resource]  aIn: FINAN, T. M.; O'BRIAN, M. R.; LAYZELL, D. B.; VASSEY, J. K.; NEWTON, W. (ed.). Nitrogen fixation: global perspectives: Proceedings of the 13th International Congress on Nitrogen Fixation, Hamilton, Ontario, Canada, 2-7 July 2001. Wallingford: CABI Publishing, 2002. p. 341-345.c2002  aSoybean (Glycine max L.) and common bean (Phaseolus vulgaris L.) are the main legume crops grown in Brazil and in some South America countries. Tn Brazil, 32 million soybean grains are produced in 12.8 million hectares with average yield of 2500 kg ha. Farmers desiring high profits employ high technology and large land areas destined for crop exportation. A similar situation is verified in neighboring countries like Argentina and Paraguay. Unlike soybean, common beans are mainly cropped for food by smallholders with a low level of technology resulting in average yield of only 700 kg ha” in 4.5 million hectares.  aNitrogen fixation  aFixação de Nitrogênio1 aHUNGRIA, M.