Responses of atrazine degradation and native bacterial community in soil to Arthrobacter sp strain HB-5

The bioremediation of soil contaminated with organic pesticides is a safe and effective approach to remove pollutants from the soil. However, whether the invasion of foreign aid organisms affects the local organisms has received increasing attention in recent years. Therefore, the purpose of this study was to examine the degradation ability of atrazine by the strain HB-5 and evaluate its effects on natural bacterial communities in a miniature pot experiment. Results showed that HB-5 accelerated the degradation of atrazine and the degradation half-life of atrazine was 3.3 times less than the natural soil. Additionally, HB-5 increased the quantities of indigenous bacteria, the microbial biomass carbon and the Shannon, Simpson and McIntosh diversity indices of soil microbes in its early stage of use, But these parameters in soil treated with HB-5 decreased to values as low as those found in the control at the later stage of incubation. These suggested that the bacteria vanished as atrazine was completely removed. These results demonstrated that Arthrobacter sp. strain HB-5 had great potential and would be an effective and environmental friendly technique to remove atrazine from the contaminated soil.