链霉菌(Streptomyces)是放线菌中数量最大,分布广泛,作用繁多的一类菌,也是抗菌素的主要产生菌,故在国民经济中占有重要地位。如目前医用与农用的链霉素、土霉素、四环素、红霉素、卡那霉素、内疗素、井岗霉素、农抗—769等多种抗菌素和抗生素,都是链霉菌属菌的发酵产物。因此研究其生态分布规律和拮抗性能对寻找新的抗生菌资源有重要意义。链霉菌在土壤里分布广泛,并受生物、气候与耕作技术等条件的影响,因此,在不同自然条件和不同类型土壤里,它的组成与分布有一定差异。目前对其分布情况知之不多,我省研究资料尤缺。近几年,我们对陕西省主要土类及其不同利用条件下的链霉菌属菌的分 Streptomyces is the largest number of actinomycetes, widely distributed, a wide range of role of a class of bacteria, but also the main antibacterial bacteria, it plays an important role in the national economy. Such as the current medical and agricultural streptomycin, oxytetracycline, tetracycline, erythromycin, kanamycin, endothelin, Jinggangmycin, agricultural anti-769 and other antibiotics and antibiotics, are Streptomyces Fermentation product of bacteria. Therefore, the study of its ecological distribution and antagonistic properties of the search for new resources of antibiotics is of great significance. Streptomyces widely distributed in the soil, and biological, climatic and farming techniques and other conditions, therefore, in different natural conditions and different types of soil, its composition and distribution of a certain difference. At present, little is known about the distribution of the province’s research data. In recent years, we classify the main soils of Shaanxi Province and Streptomyces under different utilization conditions