趋化性（Chemotaxis）是线虫最常见的行为之一，线虫通过感应化感物质，区分食物、危险等环境因子，从而产生趋化或逃避等一系列的应激行为。我们近期的研究发现，根际芽孢杆菌对南方根结线虫有显著的吸引和驱避作用，进一步实验表明，线虫的趋化性与芽孢杆菌产生的某些化学物质相关，但目前针对植物寄生线虫的趋化性和化感物质的相关研究甚少。本项目拟利用色谱和波谱手段分离和鉴定芽孢杆菌产生的影响南方根结线虫趋化性的化感物质，利用RNAi和Real time PCR技术研究在这些化感物质作用下线虫趋化性相关基因的表达变化，探讨芽孢杆菌作用于线虫趋化性的机制，为利用根结线虫的趋化性，开发新型生防制剂提供理论支撑。

Chemotaxis is one of the most common behavior of nematode. Allelochemicals help nematode react to food, danger, and different environmental factors. Such reactions induced attraction or escape behavior of nematodes. Rhizosphere Bacillus spp. was found to attract and repel Meloidogyne incognita significantly. Further experiments showed that chemotaxis behavior related to certain chemicals produced by Bacillus. This project intends to use chromatography and spectral method to separate and identify allelochemicals related to chemotaxis of root knot nematodes from Rhizosphere Bacillus. RNAi and Real time PCR technique was used to study related gene expression changes under allelochemicals induction. Exploration of the role of Bacillus in nematodes chemotaxis regulation would provide new technology to control root knot nematodes.