土壤修复剂协同昆虫病原线虫对黄瓜根际土壤线虫群落的影响

Effect of Entomopathogenic Nematode Combining with Soil Amendment on Soil Nematode Community Structure in Rhizosphere of Cucumber

为探索土壤修复剂(soil amendment,SA)协同昆虫病原线虫(Heterorhabditis beicherriana)对南方结节线虫(Meloidogyne incognita)的抑制作用以及对黄瓜根际土壤生态环境的影响,以‘千秋1号’黄瓜为试验品种,采用室内盆栽试验方法,通过设置6个试验组对黄瓜根际土壤线虫群落结构、生态多样性和功能多样性等方面进行研究。结果显示,试验60 d后施入SA和昆虫病原线虫相比其他处理根结植物类寄生线虫减少,小杆属和中杆属等食细菌类线虫增多;营养类群指数和基础成分指数均有所回升,线虫通路比指数显著升高,土壤有机分解以细菌分解为主;线虫区系仍位于土壤养分较好且以细菌降解为主的A区,其他组则从A区逐渐下降到D区。研究表明,SA协同昆虫病原线虫能有效抑制南方根结线虫,同时可以提高土壤线虫的多样性,有效缓解土壤食物网结构退化的趋势。

To investigate the inhibitory effect of soil amendment(SA)in combination with entomopathogenic nematode(Heterorhabditis beicherriana)on Meloidogyne incognita,and its impact on the ecological environment of cucumber rhizosphere soil,we used the cucumber cultivar‘Qianqiu No.1’as the test variety,and set up six different experimental groups to study the community structure of soil nematode,ecological diversity and functional diversity of cucumber rhizosphere soil.The results showed that after 60 days of experiment,the SA and nematode H.beicherriana group contained fewer parasitic nematodes in root nodules,and more Rhabditis and Mesorhabditis nematodes.The trophic diversity and basal index were increased,and the nematode channel ratio was significantly increased,and the soil organic decomposition was mainly bacterial decomposition.The nematode population remained predominantly in area A,characterized by better soil nutrients and bacterial decomposition,whereas in other groups,there was a gradual decrease from area A to area D.The results showed that the SA soil restorer combined with entomopathogenic nematode(H.beicherriana)could effectively inhibit M.incongnita,and at the same time improve the diversity of soil nematodes,effectively alleviate the degradation trend of soil food web.