杀菌剂及生防菌对白菜根肿病和土壤微生物的影响

Effects of Fungicides and Biocontrol Bacteria on Chinese Cabbage Clubroot and Soil Microorganisms

以白菜为试材,采用宏基因测序的方法,分析了不同杀菌剂及生防菌对白菜根肿病的防控效果和土壤微生物的影响,以期为改进并探寻合适的根肿病防控方式提供参考依据。结果表明:氟啶胺、氰霜唑和生防菌处理均能有效抑制白菜根肿病的发生,并且显著提高了大白菜的单株产量,以氟啶胺和芽孢杆菌联合施用对白菜根肿病的防控效果最好,其相对防效为100.0%,单株产量提高了50.2%。杀菌剂及芽孢杆菌处理均降低了微生物多样性和丰富度,对真菌群落有较大的影响,对细菌群落影响较小,尤其是施用芽孢杆菌处理。各处理对根际土壤细菌和真菌优势菌群有重要影响,主要增加的细菌优势菌属Chujaibacter、Chitinophagaceae-uncultured、Bradyrhizobium的OTUs数量,降低了真菌优势菌属Aspergillus、Rhizopus、Arrhenia的OTUs数量。病情指数与白菜根肿病致病菌Plasmodiophora的相关系数较小,与Arrhenia呈显著正相关(0.586)。

Taking Chinese cabbage as test material, the effects of different fungicides and biocontrol bacteria on the prevention and control of cabbage clubroot and the influence of soil microorganisms were analyzed by using the method of macro gene sequencing, in order to provide reference for improving and exploring appropriate prevention and control methods of Chinese cabbage clubroot.The results showed that the treatments of haloperidol, hydrochlorazole and biocontrol bacteria could effectively inhibit the occurrence of clubroot and significantly improve the yield per plant of Chinese cabbage.The combined application of haloperidol and biocontrol bacteria had the best effects on the prevention of Chinese cabbage clubroot, and the relative control effects was 100.0%,the yield per plant increased by 50.2%.The treatments reduced microbial diversity and richness, and had important impact on fungal community and little impact on bacterial community,especially biocontrol bacteria treatment.It changed the dominant flora of bacteria and fungi in rhizosphere soil with the use of fungicides and biocontrol bacteria.It mainly increased the OTUs of the bacterial genus as Chujaibacter,Chitinophagaceae-uncultured,Bradyrhizobium,and decreased the OTUs of the fungal genus as Aspergillus,Rhizopus,Arrhenia.The correlation coefficient was small between the disease index and the OTUs of Plasmodiophora,and there was a significant positive correlation with Arrhenia(0.586).