轮作与连作对烟田土壤微生物区系及多样性的影响

为探讨轮作与连作对烟田根际土壤微生物群落的影响,采用实验室微生物培养联合微生物高通量测序技术,分析了玉米-烤烟轮作和烟叶连作对烟株根际土壤微生物数量、群落结构及其多样性的影响。研究结果表明,轮作烟田根际土壤中可培养细菌和放线菌数量均高于连作烟田根际土壤,但真菌数量低于连作烟田。土壤高通量测序结果表明,轮作烟田根际土壤真菌和细菌群落多样性均高于连作烟田;在烟株的生长过程中,轮作和连作烟田在旺长期和成熟期微生物群落相似度降低。相较于黑胫病/根腐病/根结线虫发病率较高(36. 67%)的连作烟田来说,轮作烟田发病率较低(0%),进一步分析真菌和细菌群落结构发现,轮作烟田根际土壤中拮抗菌如Sphingomonas (鞘脂单胞菌属)、Pseudomonas (假单胞菌属)、Aspergillus (曲霉属)等相对丰度均高于连作烟田,而连作烟田根腐病病菌Pythium (腐霉属)丰度较高。

Effects of rotation and continuous cropping on soil microflora and diversity in tobacco field

In order to investigate the effects of rotation and continuous cropping on the soil microflora of tobacco fields,the microbial population,community structure and diversity of maize tobacco rotation and tobacco continuous cropping were analyzed by laboratory microbial culture combined with microbial high throughput sequencing.The results showed that the number of culturable bacteria and actinomycetes in the rhizosphere soil of maize tobacco rotation was higher than that of continuous cropping tobacco field,but the number of cultivable fungi was lower.The results of soil high throughput sequencing showed that the diversity of soil fungi and bacterial communities in rhizosphere soil of maize tobacco rotation was higher than that of continuous cropping tobacco field.In the process of tobacco plant growth,the similarity of microbial community decreased during the vigorous growth and mature stages.The incidence of black shank,root rot and root knot nematode of maize tobacco rotation was lower(0%)than that of continuous cropping tobacco field with high incidence of root knot nematode (36.67%).The results also showed that the relative abundance of antagonistic bacteria such as Sphingomonas,Pseudomonas and Aspergillus of maize tobacco rotation soil were higher than those of continuous cropping but the root rot pathogen Pythium appeared in the rhizosphere soil of continuous cropping tobacco field.