Abstract:The DNA sequence diversity in four soil microbial communities affected by agricultural chemicals was evaluated by using random amplified polymorphic DNA(RAPD)fingerprints.The results showed that these soil microbial communities had differences at DNA sequence richness,diversity index and evenness.The changes in the soil microbial community diversity by agricultural chemicals were found at the DNA level.It was suggested that enrichment or loss of some microbial species may occur in the soils polluted by fert...