科学实践证明,玉米和豆类混种,豆类根系上的根瘤菌,不仅给豆类,而且给玉米供应氮素养分。此外,豆类强大的主根系,对土壤中的难溶营养物质有很强的吸收性能。它透入土壤深层,吸取磷、钙及其它重要营养成分。这些营养成分被输送到根系的上部,在新陈代谢的过程中,以某种方式被利用;而它的剩余部分,则被根毛分泌到土壤表层而被玉米根系吸收。至于玉米,“不得不对豆类予以报答”。它有很大数量的须根分布在土壤表层,当土壤通气良好,并在精心管理的条件下,可分泌较多的酸来溶解土壤中难溶于水的有机或无机的物质,使之变为可吸收的营养成分。这样,通过玉米、 Scientific practice has proved that corn and beans mixed, Rhizobium on the roots of beans, not only to beans, but also to supply corn nitrogen nutrients. In addition, the powerful main root system of legumes has strong absorption properties of insoluble nutrients in the soil. It penetrates deeper into the soil, absorbing phosphorus, calcium and other important nutrients. These nutrients are delivered to the upper part of the root system and are used in some way during metabolism; the rest of it is excreted in the soil surface by root hairs and absorbed by the corn roots. As for corn, “I have to repay beans.” It has a large number of fibrous roots distributed over the surface of the soil. When the soil is well-aerated and under well-regulated conditions, more acid is secreted to dissolve the poorly water-soluble organic or inorganic material in the soil, making it Absorbable nutrients. In this way, through corn,