鲁西南地区土壤放线菌的生态分布

采用稀释平板分离法研究了鲁西南地区5种不同利用方式的土壤中放线菌的数量和组成,及与生态因子的关系,借以研究鲁西南地区土壤放线菌的生态分布。结果表明:①鲁西南地区土壤放线菌数量受多种因素影响:随土壤质地的不同而变化,其顺序为壤土>砂土>粘土。因作物或植被种类的变化而变化,在供试的5种植被中,土壤放线菌数量按菜地>小麦地>花生地>裸土>林地的顺序排列。随土层深度的加深而减少;②土壤放线菌的组成较复杂,共分离到5个属的放线菌,以链霉菌为主,其次为小单孢菌属和马杜拉放线菌属。土壤放线菌组成的复杂程度随作物变化而变化;③链霉菌的组成较复杂,共分离到13个类群,以白孢类群为主,其次为浅紫灰类群和黄色类群;④鲁西南地区土壤放线菌数量与土壤有机质、pH密切相关:土壤有机质越丰富,pH越高,放线菌数量越多;⑤鲁西南地区土壤放线菌的数量较大,是放线菌的良好栖息地。

Ecological distribution of actinomycetes in the southwest part of Shandong province

The actinomycetes quality and population of the representative crops,and the relation between actinmycetes quality and several ecological factors in Luxinan district were studied by plate screening,so that we can study the ecological distribution of actinomycetes in this district. The results indicated that: ①The population of actinomycetes in this district was influenced by many factors.It changed as Loamy soil>Sand soil>Clay soil; it changed with different types of plants: vegetable soil>wheat soil>peanut soil>bare soil>forestry soil;and it also decreased with the deeper of the soil layer.②The components of actinomycetes in this district were complicated and strains tested could be classified into five generas.Streptomyces occupied a dominant position,followed by Micromonospora and Nocardia.The complicated degree of actinomycetes changed as the crop changed.③The components of Streptomyces were also complicated and 13 subgeneras could be recognized.The dominant subgenera was Albosporus,and then the Lavendulae and Flavus.④The quality of actinomycetes was connected with the organic matter and pH value of the soil.The richer of the organic matter and the higher pH value of the soil,the larger of the population of the actinomycetes was.⑤The population of the actinomycetes in Luxinan district is large,so this district is a good place for actinomycetes to live and reproduce.