大豆接种根瘤菌以增强固氮能力 ,有助于磷钾肥的吸收 ,当接种适量的根瘤菌时 ,在相同磷钾肥基础上 ,施以不同量级的氮素在一定范围内 ,随着施氮量的增加 ,固氮能力加强 ,生物产量明显提高。试验结果表明 ,以施氮量 1 87.5kg/hm2 增产效果最明显 ,超过 1 87.5kg/hm2 产量有下降趋势 Soybean inoculation rhizobia to enhance nitrogen fixation capacity is conducive to the absorption of phosphorus and potassium fertilizer, when inoculated with the appropriate amount of rhizobia, on the basis of the same phosphorus and potassium fertilizer, applying different levels of nitrogen within a certain range, with the amount of nitrogen Increased nitrogen fixation capacity, bio-yield increased significantly. The results showed that the yield was most obvious when the nitrogen application rate was 1 87.5kg / hm2, and the yield more than 1 87.5kg / hm2 had a downward trend