紫云英是一种高产的绿肥,在我省种植的历史不长。提高紫云英鲜草产量,对提高粮食作物产量有很大的作用。实践证明,种植紫云英接不接种根瘤菌,是关系到紫云英有收无收、多收少收的一项关键技术措施。紫云英根瘤菌有独特的专一性,只能与紫云英共生才能固定空气中的氮素,促进紫云英生长。我省种植过紫云英的士壤,紫云英根瘤菌的有效数少,新区种紫云英的士壤,紫云英根瘤菌就更少。因此,种植紫云英必须 Ziyunying is a high-yielding green manure that has not been cultivated in our province for a long time. Increasing the yield of fresh milkvetch has a great effect on improving the yield of food crops. Practice has proved that the planting of Chinese milk vetch is not inoculated rhizobia, is related to the astragalus received confiscated, more than a closing income of a key technical measure. Astragalus Rhizobium has a unique specificity, can only coexist with the milk vetch to fix the nitrogen in the air, promote the growth of milk vetch. The province has planted astragalus peduncle, Astragalus Rhizobium effective number less, the new species of Astragalus pedicella, Astragalus Rhizobium less. Therefore, the cultivation of vetiver must