Li Haifeng, Wang Yuanli, Fu Jiake, Hu Shuang, Qu Jianhang
College of Biological Engineering, Henan University of Technology, Zhengzhou, 450001 Henan China.
3 Biotech. 2020 Feb;10(2):67. doi: 10.1007/s13205-020-2056-2. Epub 2020 Jan 24.
The biodegradation of acetochlor in solution and soil and improvements in the growth of maize seedlings by a phosphate-solubilizing bacterial strain were investigated in this research. The strain sp. ACD-9 optimally degraded acetochlor at pH 6.0 and 42 °C in solution. And acetochlor with an initial concentration of 30 mg/L was efficiently (> 60%) degraded by the strain after 2 days in solution. Acetochlor biodegradation and the resulting beneficial products were also identified by LC-MS, and the probable degradation products of acetochlor and two kinds of plant growth hormones, namely, 2-chloro--(2-methyl-6-ethylphenyl) acetamide (CMEPA), indoleacetic acid (IAA), and zeatin, were detected from the fermentation broth of strain ACD-9. The effects of the strain on the growth and acetochlor accumulation of maize seedlings were also analyzed in laboratory-scale pot experiments. Inoculation of the strain in soil could significantly improve growth (> 9.4%) and phosphorus uptake (> 14.8%) and decrease the accumulation (> 70%) and toxic effects of acetochlor on seedlings. Taking the results together, strain ACD-9 may be useful in the degradation of acetochlor in soil and promotion of the growth and phosphorus uptake of maize.
本研究考察了溶液和土壤中乙草胺的生物降解以及一株解磷细菌对玉米幼苗生长的促进作用。菌株ACD-9在溶液中pH值为6.0、温度为42℃时对乙草胺的降解效果最佳。初始浓度为30mg/L的乙草胺在溶液中经该菌株处理2天后被高效降解（>60%）。通过液相色谱-质谱联用仪（LC-MS）对乙草胺的生物降解及其产生的有益产物进行了鉴定，从菌株ACD-9的发酵液中检测到了乙草胺可能的降解产物以及两种植物生长激素，即2-氯-N-(2-甲基-6-乙基苯基)乙酰胺（CMEPA）、吲哚乙酸（IAA）和玉米素。在实验室规模的盆栽试验中还分析了该菌株对玉米幼苗生长和乙草胺积累的影响。在土壤中接种该菌株可显著促进玉米幼苗生长（>9.4%）和磷吸收（>14.8%），并减少乙草胺在幼苗中的积累（>70%）及其毒性作用。综合研究结果，菌株ACD-9在土壤中乙草胺的降解以及促进玉米生长和磷吸收方面可能具有应用价值。
