枯萎病对菊花根际土壤微生物群落结构的影响

Fusarium Wilt Changes Microbial Community Structure in Rhizosphere Soil of Chrysanthemum morifolium

目的:探究患枯萎病菊花与健康菊花根际土壤微生物群落的差异。方法:以患病菊花植株和健康菊花植株根际土壤为研究材料,采用高通量测序技术对患病植株和健康植株样本的细菌16S rDNA和真菌内部转录间隔区(ITS)基因进行序列测定并进行数据分析。结果:枯萎病的发生降低了菊花根际土壤中细菌种群的丰富度和多样性程度,但对根际土壤中的真菌α-多样性无明显影响。菊花健康植株根际土壤细菌微生物中酸杆菌门、芽单胞菌门、硝化螺旋菌门占比高于患病植株,而变形菌门、拟杆菌门占比低于患病植株(P<0.05)。菊花患病植株根际土壤中镰刀菌属(Fusarium)真菌占比分别为27.49%,14.53%,11.94%,而健康植株镰刀菌属真菌占比分别为0.47%,1.01%,0.67%。菊花患病植株根际土壤中会出现细菌性致病菌果胶杆菌属(Pectobacterium)和菊迪基氏菌属(Dickeya),而健康植株根际土壤中硝化类细菌、解毒类细菌、光合细菌等丰度高于患病植株。结论:患有枯萎病地块菊花植株根际土壤微生物中细菌的物种多样性和丰富度降低,并大量富集镰刀菌属致病真菌和积累果胶杆菌属与菊迪基氏菌属致病细菌,而健康菊花植株根际土壤微生物有益菌占比明显高于患病植株。

Objective:To explore the differences in rhizosphere microbial community structure between Fusarium wilt-infected and healthy Chrysanthemum morifolium plants. Method: The rhizosphere soils of diseased and healthy C. morifolium plants were sampled and subjected to high-throughput 16S ribosomal DNA(rDNA)and internal transcribed spacer(ITS)sequencing,to identify the microbial community structure including bacteria and fungi. Result: Fusarium wilt reduced the bacterial abundance and diversity but had no significant effect on fungal alpha-diversity. The proportions of Acidobacteria, Gemmatimonadetes, and Nitrospirae in rhizosphere soil of healthy C. morifolium plants were higher than those of diseased plants,while the proportions of Proteobacteria and Bacteroidetes were lower(P<0.05). Fusarium fungi accounted for 27.49%,14.53%,and 11.94% in diseased plants whereas 0.47%,1.01%,and 0.67% in healthy plants.Pathogenic bacteria Pectobacterium and Dickeya were enriched in rhizosphere soil of diseased plants. The abundances of nitrifying,detoxifying,and photosynthetic bacteria in rhizosphere soil of healthy plants were higher than those of diseased plants. Conclusion: Fusarium wilt reduces the bacterial richness and diversity and triggers the enrichment of massive Fusarium fungi,Pectobacterium,and Dickeya. The proportion of beneficial bacteria in rhizosphere soil of healthy plants is significantly higher than that of diseased plants.