Department of Agricultural Chemistry, National Taiwan University, Taipei.
J Environ Sci Health B. 2012;47(1):13-21. doi: 10.1080/03601234.2012.601944.
This investigation was undertaken to examine the dissipation rate of pyriproxyfen as well as the change in the soil bacterial community. Residues of pyriproxyfen were measured using high performance liquid chromatography (HPLC) and the changes in bacterial community were determined by comparing the 16S rDNA bands on patterns by denaturing gradient gel electrophoresis (DGGE). The dissipation of pyriproxyfen was affected by both the concentration applied and incubation temperature. Lower concentrations (1 mg Kg(-1)) and higher incubation temperatures (30 and 40°C) showed more rapid dissipation rates. The population of microbial community decreased rapidly after incubation with 10 mg Kg(-1) of pyriproxyfen for 91 days, indicating the toxicity of pyriproxyfen toward bacterial communities in a closed soil ecosystem. Lower concentrations of pyriproxyfen showed less toxicity toward the microbial community. From cluster analysis, the structure of the bacterial community showed roughly a 60 % similarity throughout the experiment period in the control experiment, indicating the stability within soil microbiota without chemical agitation. However, the similarity was lower than 50 % both in the one and 10 mg Kg(-1) of insecticide pyriproxyfen spiked experiment, indicating the soil bacterial community changed after the insecticide pyriproxyfen was applied.
本研究旨在考察吡丙醚在土壤中的消解动态以及土壤细菌群落的变化。采用高效液相色谱法（HPLC）测定吡丙醚残留量，用变性梯度凝胶电泳（DGGE）比较图谱上的 16S rDNA 条带来确定细菌群落的变化。吡丙醚的消解受施用量和培养温度的影响。较低浓度（1mg/kg）和较高培养温度（30 和 40°C）下，消解速度更快。用 10mg/kg 的吡丙醚处理 91 天后，微生物群落的数量迅速减少，表明吡丙醚对封闭土壤生态系统中细菌群落具有毒性。较低浓度的吡丙醚对微生物群落的毒性较小。从聚类分析来看，在对照实验中，整个实验期间细菌群落的结构大约有 60%的相似性，表明在没有化学搅拌的情况下，土壤微生物区系具有稳定性。然而，在添加 1mg/kg 和 10mg/kg 吡丙醚的杀虫剂处理实验中，相似性均低于 50%，表明在施用杀虫剂吡丙醚后，土壤细菌群落发生了变化。
