烟草青枯病发病烟株根际土壤细菌群落分析

Analysis of bacterial community in rhizosphere soil of tobacco plant infected by bacterial wilt disease

【目的】研究青枯病发生对根际土壤细菌群落组成的影响,探明影响根际土壤细菌群落的环境因子。【方法】采用宏基因组学高通量测序技术,比较发病烟株和健康烟株根际土壤细菌群落差异。【结果】(1)健康烟株根际土壤细菌Ace指数、Chao指数和Shannon指数有高于发病烟株的趋势,而Simpson指数有低于发病烟株的趋势;(2)发病烟株根际土壤中芽孢杆菌属(Bacillus)、假单胞菌属(Pseudomonas)和链霉菌属(Streptomyces)等益生菌减少,而劳尔氏菌属(Ralstonia)和Rudaea等病原菌增加;(3)土壤pH、有效磷(AP)、交换性钙(Ca)和有效铜(Cu)含量在发病烟株根际土壤中显著减少,而速效钾(AK)含量显著增加。【结论】与健康烟株根际土壤相比,发病烟株根际土壤细菌多样性、有益菌丰度、土壤pH和养分含量都较低;pH、P、K、Ca、Cu是对根际土壤细菌群落影响较大的土壤环境因子。

This paper aimed to study effects of bacterial wilt on bacterial community composition in rhizospere soil,and to explore the environmental factors affecting bacterial community in rhizosphere soil.Metagenomic high-throughput sequencing technology was used to compare bacterial community in rhizosphere soil between disease infected by plant and healthy plant.Results showed that(1)Ace index,Chao index and Shannon index in rhizosphere soil of healthy tobacco plants were higher but Simpson index was lower than those of disease infected bytobacco plants.(2)In rhizosphere soil of infected by tobacco plants,beneficial bacteria such as Bacillus,Pseudomonas and Streptomyces decreased,while pathogenic bacteria such as Ralstonia and Rudaea increased;(3)Soil pH,available phosphorus,exchangeable calcium,available copper content decreased signifi cantly in infected by tobacco plants,while available potassium content increased signifi cantly.It was concluded that bacterial diversity,benefi cial bacteria abundance,soil pH and nutrient contents in rhizosphere soil of disease infected by tobacco plants were lower;pH,P,K,Ca,and Cu had greater impact on rhizosphere soil bacterial community.