基于代谢组学分析根腐病西洋参根际土壤特异代谢物

Analysis of Specific Metabolites in Rhizosphere Soil of Panax quinquefolius L.with Root Rot Diseases Based on Metabolomics

以4年生健康西洋参根际土壤(healthy ginseng soil,HS)和患根腐病西洋参根际土壤(root rot ginseng soil,RS)为研究对象,采用基于气相色谱-飞行时间质谱联用技术(GC-TOF-MS)的代谢组学方法分析根际土壤差异代谢产物。RS vs HS组共筛选到13个具有显著性差异(P<0.05)的代谢产物,其中包括9种有机酸、3种糖类和1种萜类。与HS组相比,RS组中二十四烷酸、棕榈酸、巴豆酸、苯甲酸、油酸、十七烷酸、壬二酸、水杨酸和儿茶酸的水平显著升高(P<0.05),而D-塔罗糖、甘露糖、N-乙酰-D-半乳糖胺和植醇的水平显著降低(P<0.05)。KEGG通路富集分析发现这些差异代谢产物主要富集在不饱和脂肪的生物合成、次生代谢物的生物合成、微生物在不同环境中的代谢及芳香族化合物的降解等10条代谢通路中。根腐病西洋参和健康西洋参根际土壤存在一些显著差异的代谢产物,这些差异代谢产物可能通过化感作用导致西洋参根腐病的发生,本研究为进一步研究西洋参的化感作用提供了理论依据。

The metabolomics method based on gas chromatography-time-of-flight mass spectrometry(GC-TOFMS)was used to analyze rhizosphere soil differential metabolites,and the rhizosphere soil of healthy ginseng(HS)and root rot ginseng(RS)with 4-year-old were chosen as research objects.13 metabolites with significant differences(P<0.05)were screened in the RS vs HS group,including 9 organic acids,3 carbohydrates,and 1 quinone.Compared with HS group,lignoceric acid,palmitic acid,cerotinic acid,benzoic acid,oleic acid,heptadecanoic acid,azelaic acid,salicylic acid and 3,4-dihydroxybenzoic acid level was significantly increased(P<0.05)in RS group,and D-Talose,mannose,N-Acetyl-D-galactosamine and phytol were significantly decreased(P<0.05).KEGG pathway enrichment analysis found that these differential metabolites were mainly enriched in 10 metabolic pathways,including biosynthesis of unsaturated fatty acids biosynthesis of secondary metabolites,microbial metabolism in diverse environments and degradation of aromatic compounds.Root rot P.quinquefolius L.and healthy P.quinquefolius L.rhizosphere soil have some significantly different metabolites,and these different metabolites may cause the occurrence of P.quinquefolius L.root rot through allelopathic effects.This study provided theoretical basis for further research on the allelopathy of P.quinquefolius L..