大豆有根瘤菌共生固氮,不宜过多地施用氮肥。施用根瘤菌是提高大豆固氮效率、增加产量行之有效的方法,一般可增产15～30%。1.大豆根瘤菌的简易生产及施用方法(1)干瘤法:在大豆开花期选择健壮植株连根挖起,选用主根和支根上部聚有大型的切开呈粉红色根瘤的植株,剪去枝叶、须根和下部支根,挂在背阴处风干备用。也可在收获时选根,用量比开 Soybean Rhizobium symbiotic nitrogen fixation, nitrogen fertilizer should not be applied too much. Rhizobium is to improve nitrogen fixation efficiency of soybean, increase production is an effective method, the general increase of 15 to 30%. 1. Simple soybean rhizobia production and application methods (1) Dry tumor method: choose strong plants in the flowering period of soybean dig up roots, the selection of the main roots and branches of the upper part of a large cut pink root nodules plants, cut To the branches, fibrous roots and roots, hanging in the shade dried spare. Roots can also be selected at harvest, the amount of open than