Exploring bacterial community structure and function associated with atrazine biodegradation in repeatedly treated soils
Exploring bacterial community structure and function associated with atrazine biodegradation in repeatedly treated soils
复制标题
探索反复处理土壤中与莠去津生物降解相关的细菌群落结构和功能
DOI：
10.1016/j.jhazmat.2015.01.006
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发表时间：
2015-04-09
影响因子：
13.6
通讯作者：
Yu, Yunlong
中科院分区：
文献类型：
--
作者：
Fang, Hua;Lian, Jianjun;Yu, Yunlong
除草剂阿特拉津在农业中的大量使用导致了持续的污染，这可能会损害后茬作物，并对土壤生态和环境健康构成潜在威胁。研究了阿特拉津在推荐剂量、2倍剂量和5倍剂量3个重复处理下的降解特性和土壤细菌群落结构与功能的动态变化及其相互关系。结果表明，阿特拉津的降解半衰期随处理频率的增加而明显缩短。土壤微生物功能多样性呈现抑制-恢复-刺激的变化趋势，与阿特拉津的降解速率增加有关。进行16 S扩增子测序以探索细菌群落结构并将属与潜在的阿特拉津降解相关联。共发现7种潜在的阿特拉津降解细菌属，包括Nocardioides，节杆菌属，慢生根瘤菌属，伯克霍尔德氏菌属，甲基杆菌属，分枝杆菌属和梭菌属。这些细菌属表现出几乎完整的阿特拉津降解途径，包括脱氯，脱烷基化，羟基化，开环。此外，其中四种的相对丰度（即，Nocardioides，节杆菌，甲基杆菌，慢生根瘤菌）的处理频率和阿特拉津浓度增加，这表明他们可能参与阿特拉津降解过程中重复处理。我们的研究结果揭示了阿特拉津降解和土壤细菌群落结构之间的潜在关系，在反复处理的土壤。(C)2015 Elsevier B. V.版权所有。
Substantial application of the herbicide atrazine in agriculture leads to persistent contamination, which may damage the succeeding crops and pose potential threats to soil ecology and environmental health. Here, the degradation characteristics of atrazine and dynamic change of soil bacterial community structure and function as well as their relations were studied during three repeated treatments at the recommended, double, and five-fold doses. The results showed that the degradation half-life of atrazine obviously decreased with increased treatment frequency. Soil microbial functional diversity displayed a variation trend of suppression-recovery-stimulation, which was associated with increased degradation rate of atrazine. 16S amplicon sequencing was conducted to explore bacterial community structure and correlate the genus to potential atrazine degradation. A total of seven potentially atrazine-degrading bacterial genera were found including Nocardioides, Arthrobacter, Bradyrhizobium, Burkholderia, Methylobacterium, Mycobacterium, and Clostridium. These bacterial genera showed almost complete atrazine degradation pathways including dechlorination, dealkylation, hydroxylation, and ring cleavage. Furthermore, the relative abundance of four of them (i.e., Nocardioides, Arthrobacter, Methylobacterium, and Bradyrhizobium) increased with treatment frequency and atrazine concentration, suggesting that they may participate in atrazine degradation during repeated treatments. Our findings reveal the potential relationship between atrazine degradation and soil bacterial community structure in repeatedly treated soils. (C) 2015 Elsevier B.V. All rights reserved.