Effect of cephalosporin residue organic fertilizer on resistant bacteria and related resistance genes in maize soil
[Objective]To explore the effect of cephalosporin residue organic fertilizer on the abundance of drug-resistant bacteria and related resistance genes in the maize soil,and to provide scientific basis for bi-ological safety evaluation in the application of cephalosporin residue organic fertilizer.[Methods]Three ex-perimental groups were set up,which included none organic fertilize treatment(CK),the organic fertilizer treatments with 500 kg/667 m2(B1)and with 1000 kg/667 m2(B2),respectively.The antibiotic resistant bacteria and related antibiotic resistance genes(ARGs)with different treatments were analyzed by using the cultivable method and the real-time fluorescence quantitative PCR.[Results]The results showed that the to-tal number of bacteria was significantly increased in the treatments with cephalosporin residue organic fertiliz-er,and the number of cefradine resistant bacteria was significantly increased in the treatments at corn seedling stage as well.Forty-one strains of antibiotic-resistant strains were obtained,among which 8 cefradine resist-ant strains belonged to 6 genera.[Conclusion]The relative abundance of ARGs genes in corn seedling soil was significantly increased in the treatments with cephalosporin residue organic fertilizer.There were no signifi-cant effects on the relative abundance of bla TEM gene in the treatments at the fruiting stage,and none regular influence on other drug-resistant genes.