Isolation, identification, and characterization of atrazine-degrading bacterial strain AD111

Abstract:

[Background] In maize-soybean rotation system, the residual atrazine in maize field may influence the next crop soybean. [Objective] To screen an atrazine-degrading strain from the field soil in Anda City, Heilongjiang Province and explore the degradation characteristics. [Methods] A highly efficient strain was isolated and screened by enrichment culture method, and identified based on morphological observation, physiological and biochemical determination, and 16S rRNA sequencing. Different carbon sources, pH, temperatures, and atrazine concentration were set to explore the optimal fermentation and degradation conditions with the simple variable method. [Results] A highly efficient atrazine-degrading strain AD111 was screened out, which used atrazine as the sole nitrogen source in basic salt medium-glucose (BSM-G). It was identified as Achromobacter marplatensis. The optimal temperature, pH, and carbon source for atrazine degradation by AD111 were 35℃, pH 8.0, and sucrose. Within 24 h, it degraded 99.7% and 81.9% of atrazine at 50 mg/L and 300 mg/L, respectively. [Conclusion] AD111 has exceptional environmental adaptability and atrazine-degrading ability, which can remove the atrazine residue in alkaline land in Heilongjiang Province.

Key words:atrazine;biodegradation;crop rotation;Achromobacter marplatensis