生产实践和科学试验结果表明:大豆迎茬减产达10%,重茬减产达20%,随着重茬年限的增加,减产愈加严重,而且重迎茬还会导致大豆的品质下降,蛋白质和脂肪含量降低。重迎茬大豆减产是多种因素综合作用的结果,但主要的原因是土传病害的加剧所致;重迎茬大豆根际微 The results of production practice and scientific experiment show that the yield of soybean is reduced by 10% and the yield of repeated cropping is reduced by 20%. With the increase of the number of continuous cropping, the yield reduction is more and more serious, and the heavy stubble will result in the decrease of soybean quality and the decrease of protein and fat content . Heavy cropping soybean yield reduction is the result of a combination of many factors, but the main reason is due to the aggravating of soil-borne diseases;