作为世界上第一种商品化生产的选择性除草剂，2,4-D的长期大量使用已对我国土壤和水体造成了严重污染。该类除草剂自然条件下主要依赖于微生物降解。因此，探索以微生物降解2,4-D及其降解产物，是2,4-D类除草剂产品污染治理研究的重要方向。微生物固定化技术在农药污染土壤治理中的应用处于起步阶段。本项目以2,4-D降解质粒pJP4作为可移动基因片段，运用基因强化技术构建2,4-D降解基因工程菌，并率先采用吸附、包埋和交联等固定化微生物技术对筛选出的高效2,4-D降解基因工程菌进行固定化，探索固定化最优条件，表征固定化产物的物理化学性能，进行2,4-D土壤原位修复室内模拟试验，为2,4-D的固定化微生物修复研究提供理论和技术支持，同时为我国农药污染的治理提供帮助。

As the first selective herbicides for commercialisation in the world, the long-term and misuse of 2,4-D has caused serious pollution on soil and water. After applied in crops, the 2,4-D series pesticides will eventually migrate to the soil or water, mainly depending on the microbial degradation. Therefore, to explore the microbial degradation of 2,4-D and its metabolites is an important direction to do research on the pollution control of 2,4-D series pesticides. Immobilized microorganism technology is in the initial stage to apply in soil improvement from pesticides pollution. Basing on establishing a method for 2,4-D residual analysis, this project aims to construct 2,4-D degrading genetic microorganism with gene bioaugmentation, which regarding a plasmid pJP4 as mobile genetic elements. Afterwards, several immobilized microorganism techniques are applied to 2,4-D degrading genetic microorganism, such as adsorption, embedding and crosslinking. Furthermore, the optimized immobilizing conditions, physical and chemical characteristics and the simulated test of different types of soil contaminated by 2,4-D will be researched. The project will provide theoretical and technical support for immobilized bioremediation research of 2,4-D, and provide help for pesticide pollution treatment in China.