甜玉米轮作配施万寿菊秸秆返田防治白菜根肿病机理初探

Preliminary study on the mechanism of controlling Chinese cabbage clubroot disease by applying marigold straw in sweet corn rotation

为研究甜玉米轮作配施万寿菊秸秆返田模式对白菜根肿病的防治机理,并为该种植模式提供理论基础和技术支撑,通过荧光定量PCR技术、非靶标代谢组学技术、高通量测序技术和田间试验验证,探究了甜玉米轮作配施万寿菊秸秆返田处理(CrMs)对白菜根肿病的田间防效、休眠孢子数量以及白菜根际土中代谢物和微生物种类的影响。结果表明:CrMs处理对白菜根肿病的田间防效为61.11%;土壤中根肿菌休眠孢子数量由轮作前的1×10^(5.92)个/g降到了1×10^(3.73)个/g;CrMs处理改变了白菜根际土中的代谢物组分,提高了脱氧鹅胆酸(Chenodeoxycholic acid)、α-亚麻酸(Alpha-Linolenic acid)和4-异丙基苯甲酸(4-Isopropylbenzoic acid)等代谢物含量,降低了油酸酰胺(Oleamide)和蜜二糖(Melibiose)等代谢物含量;相关性分析表明,α-亚麻酸和脱氧鹅胆酸等与根肿菌属(Plasmodiophora)相对丰度负相关,油酸酰胺等与根肿菌属相对丰度正相关;CrMs处理丰富了白菜根际微生物多样性,改善了土壤微生物群落组成,显著提高了芽胞杆菌属(Bacillus)、慢生根瘤菌属(Bradyrhizobium)、溶杆菌属(Lysobacter)和链霉菌属(Streptomyces)等的相对丰度,降低了根肿菌属、镰刀菌属(Fusarium)和螺旋线虫属(Helicotylenchus)的相对丰度。综上,甜玉米轮作+万寿菊秸秆返田的新模式是防治白菜根肿病的重要栽培措施,可为根肿病的绿色防治提供关键的技术参考。

The aims of this study were to investigate the control mechanism of sweet corn rotation combined with marigold straw returning mode on cabbage clubroot disease,and provide theoretical basis and technical support for the planting mode.Fluorescence quantitative PCR technology,non-target metabolomics technology,high-throughput sequencing technology and field test verification were used in this study to explore the field control effect of sweet corn rotation combined with marigold straw returning treatment(CrMs)on Chinese cabbage clubroot,the number of resting spores and the differences in metabolites and microbial species in rhizosphere soil of Chinese cabbage.The results showed that:The field control effect of CrMs treatment on cabbage clubroot was 61.11%.The number of resting spores in the soil decreased from 1×10^(5.92) spores per gram to 1×10^(3.73) spores per gram.CrMs treatment changed the metabolite components in the rhizosphere soil of Chinese cabbage,increased the contents of metabolites such as chenodeoxycholic acid,alpha-Linolenic acid and 4-Isopropylbenzoic acid,and decreased the contents of metabolites such as oleamide and melibiose.Alpha-Linolenic acid and chenodeoxycholic acid were negatively correlated with the relative abundance of Plasmodiophora,and oleamide was positively correlated with the relative abundance of Plasmodiophora.In addition,CrMs treatment enriched the rhizosphere microbial diversity of Chinese cabbage,improved the composition of the soil microbial community,significantly increased the relative abundance of Bacillus,Bradyrhizobium,Lysobacter and Streptomyces,and decreased the relative abundance of Plasmodiophora,Fusarium,and Helicotylenchus.In summary,the new mode of sweet corn rotation+marigold straw returning to the field is an important cultivation measure to control the Chinese cabbage clubroot,which provides a key technical reference for the green prevention and control of the clubroot.