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从棉花抗病品种连作３、６、８、９、１０ａ的土样中分离出３８３０个真菌菌落，其主要类群归入１１个真菌属。随着棉花抗病品种连作年限的增长，土壤中真菌和放线菌的种类和数量逐渐增加，而棉花枯萎菌的数量则逐渐减少。对棉枯萎菌抑制性较强的种类有：细黄链霉菌（Ｓｔｒｅｐｔｏｍｙｃｅｓｍｉｃｒｏｆｌａｖｕｓ）、球孢链霉菌黄色变种（Ｓ．ｇｌｏｂｉｓｐｖａｒ．ｆｌａｖｕｓ）和紫链霉菌淡红变种（Ｓ．ｖｉｏｌａｃｅｕｓ）。供试土样中分离到的３３１５个细菌菌落按菌落特征可分为９个类型，其中Ⅲ型和Ⅸ型对棉枯萎菌有较强的抑菌作用，初步鉴定为枯草芽孢杆菌Ｂａｃｉｌ－ｌｕｓｓｕｂｔｉｌｉｓ．和Ｂ．ｓｐ．，它们在连作年限较长的土样中出现的频率较高，但土样中细菌的总数量与棉花抗病品种连作的年代成反相关。供试土样中分离出５种主要线虫，其中螺旋线虫、滑刃线虫、真滑刃线虫的数量也随抗病棉花连作时间的延长而增加。
A total of 3,830 fungal colonies were isolated from soil-resistant cotton cultivars 3, 6, 8, 9, and 10a. The major groups were classified into 11 fungal genera. With the continuous growth of cotton resistant varieties, the number and types of fungi and actinomycetes in soil gradually increased, while the number of Fusarium wilt cotton decreased gradually. Streptomyces microflora, S. globispvar.flavus, and S. violaceus, which are more inhibitory against cotton wilt. The 3315 bacterial colonies isolated from the soil samples were classified into 9 types according to their colony characteristics. Among them, type Ⅲ and type Ⅸ had strong antibacterial activity against Fusarium oxysporum f. Sp., And were initially identified as Bacillus subtilis Bacil-lussubtilis. And B. sp. , Which appeared frequently in soil samples with longer continuous cropping years. However, the total amount of bacteria in soil samples was inversely correlated with the continuous cropping of disease-resistant cotton varieties. Five main nematodes were isolated from the soil samples tested. The numbers of Helicotidus, Euphausium spp. And Echinochloa crus-gallus were also increased with the prolongation of the resistant cotton.