挥发性物质诱吸线虫的土壤细菌系统多样性特征及其活性挥发物鉴定

Phylogenetic diversity characteristics of soil bacteria producing nematode-attracting volatiles and identification of their active compounds

摘要:

摘要:【目的】明确有机挥发物诱吸线虫的土壤细菌种群多样性及其活性挥发物，有助于了解线虫与土壤微生物间的互作关系，为利用诱吸性物质与杀线虫剂配合使用，提高防治寄生线虫效果奠定基础。【方法】通过双培养皿倒扣法筛选我国26 个省市的187 份农业土壤中挥发性诱吸线虫的细菌资源、测定其诱吸活性，并结合RFLP-16S rRNA 方法分析活性细菌的系统亲缘关系;采用SPME-GC /MS 方法鉴定其挥发物的类型，并通过纯品进行诱吸功能验证。【结果】从分离自187 份土样的3800 株细菌中，筛选出诱吸活性(AN)≥

Abstract:

Abstract:［Objective］ This study characterized the phylogenetic diversity of soil bacteria producing nematode-attracting volatiles and their nematode-attracting compounds． Results would enhance our understanding on the interaction between nematodes and soil microorganisms and potentially enhance the biocontrol efficiency when combined the attractants with nemacides． ［Methods］Bacteria producing volatiles with functions of nematode-attracting activities were isolated from 187 agricultural soil samples collected in 26 provinces of China with the method of double-Petri dishes． The phylogenetic diversity of these bacteria was characterized by RFLP-16S rRNA gene sequence analysis． The nematode-attracting volatiles of bacteria were detected using the SPME-GC /MS，and volatile compounds with attractive activity were determined by confirming with individual commercial compounds． ［Results］ Among the 3800 bacteria isolated from the 187 soil samples，196 isolates(5. 16% of the total) showed attractive activity(AN)more than 30% to Panagrellus redivivus．Of the 196 isolates，66 (1.74% ) showed AN≥70%，62 isolates ( 1. 63%) showed AN between 50% and 70% ，and 68 isolates (1.79%) showed AN less than 50%．Phylogenetic analysis revealed that the 196 bacteria were clustered into 5 groups: Bacilli，Gammaproteobacteria，Alphaproteobacteria，Sphingobacteria and Actinobacteria． But，Bacillus were the dominant，which covered 13 species． And 11 volatiles with nematode-attracting activity were determined，including benzaldehyde，2-heptanone， benzyl benzoate， ethyl palmitate， (+) -longifolene， benzyl alcohol， p-anisaldehyde，vanatone，ethyl butyrate，isovanilin and d-alaninol． ［Conclusion］ Some species of bacteria in agriculture soil can produce volatiles to attract nematodes．