降解菌2N3对被氯嘧磺隆污染土壤的生物修复

Bioremediation of chlorimuron-ethyl contaminated soil by strain 2N3

在实验室条件下,研究了高效降解菌2N3(克雷伯氏菌属,Klebsiellasp.)对被氯嘧磺隆污染土壤的修复作用及其影响因素。当土壤中氯嘧磺隆的添加浓度为20mg/kg,每1克土壤中2N3的接菌量为1×106个菌体时,第30d时土壤中氯嘧磺隆的降解率为84.6%,对照仅为13.4%;相同2N3接菌浓度下,当土壤中氯嘧磺隆浓度为100mg/kg时,其降解率为31.1%。以小麦、玉米、黄瓜为供试作物,在土壤中施加20mg/kg的氯嘧磺隆,当每1克土壤中2N3的接菌量为1×106个菌体时,小麦、玉米、黄瓜的出苗率分别为85%,82%和79%,且处理组株高高于对照,表明降解菌2N3具有明显减轻氯嘧磺隆药害的作用。研究表明,人工接种降解菌2N3可提高土壤中氯嘧磺隆的降解率,有效降低其在土壤中的残留。

Bioremediation of Klebsiella sp. 2N3 strain in chlorimuron-ethyl contamined soil was examined under laboratory conditions. When 2N3 was inoculated into the soil at the density of 1×10^6 mycelium/g dry soil,chlorimuron-ethyl （ 20 mg/kg dry soil ） in soil was degraded by 84.6% after incubated for 30 days, with blank control of 13.4% degradation rate. When chlorimuron-ethyl was increased by 100 mg/kg in soil, chlorimuron-ethyl degradation rate was below 31. 1%. With addition of chlorimuron-ethyl of 20 mg/kg in soil, and amount of strain 2N3 in 1×10^6 mycelium/g dry soil, emergence rates of wheat, corn and cucumber were 85% ,82% and 79% ,respectively. Plant heights were observed to increase in comparison with control plant. It＇s indicated that phyto-toxicity effect of chlorimuron-ethyl could be retarded by strain 2N3. The current study showed that the hand-actuated inoculation of 2N3＇s strain could effectively increase degradation rate of chlorimuron-ethyl in contaminated soil.