Abstract:

In order to study the effect of partial substitution of liquid organic fertilizer for chemical fertilizer on the bacterial community in the root zone of greenhouse tomato， chemical flushing fertilization was used as control （T_CK）， liquid organic fertilizer was set to replace 20% （T_R20）、30%（T_ R30） and 40% （T_R40） chemical flushing. 16S rRNA high-throughput sequencing technology was used to analyze the diversity， structural composition and differences of bacterial communities in different treatments. The results showed that， at 97% similarity level， 3 747 OTU， 37 phylas， 104 classes， 268 orders， 441 families， 730 genera and 1 401 species were found. There were shared 1 338 OUT in 4 treatments， and there were 140， 129 and 263 unique OTU values in T_R20， T_R30 and T_R40 treatments， respectively. The diversity of bacterial communities in T_R30 treatment was higher than other treatments， and the dominant phylums were Proteobacteria， Chloroflexi， Acidobacteria and Firmicutes， while the dominant genera were norank_c_subgroup_6、Bacillus and norank_f_A4b. Through cluster analysis， principal component analysis， non metric multi-dimensional scale analysis and co-occurrence network analysis， it was found that there were high similarity of bacterial composition between T_CK and T_R30 treatments. By PICRUSt software package， the functional composition of bacterial community showed that the main COGs were similar among four treatments， but the relative abundance of each COG changed. In conclusion， the different proportions of liquid organic fertilizer instead of chemical flushing fertilizer could increase the species of exogenous bacteria， change the richness， diversity and colony composition. And the effect of T_R30 treatment was the most excellent， which provided a theoretical basis for liquid organic fertilizer to replace chemical flushing fertilization.

Key words: greenhouse tomato, liquid organic fertilizer, inorganic fertilizer, bacterial, community structure

摘要：

为研究液态有机肥部分替代化肥对设施番茄根区细菌群落的影响，以化学冲施肥为对照（T_CK），设置液态有机肥分别替代20%（T_R20）、30%（T_R30）和40%化学冲施肥（T_R40）3个处理，应用16S rRNA 高通量测序技术，分析番茄根区土壤样本中细菌的群落多样性、结构组成和差异。结果表明，在97%的相似水平下，共发现3 747个OTU，37个门，104个纲，268个目，441个科，730个属，1 401个种。3个处理和对照样品中共有OTU为1 338个，独有的OTU数值分别为140（T_R20）、129（T_R30）和263（T_R40）。T_R30处理的细菌丰富度和多样性最高，其优势菌门为变形菌门（Proteobacteria）、绿弯菌门（Chloroflexi）、酸杆菌门（Acidobacteria）、厚壁菌门（Firmicutes）；优势菌属为norank_c_subgroup_6、芽孢杆菌属（Bacillus）、norank_f_A4b。通过聚类分析、主成分分析、非度量多维尺度分析和共现性网络分析发现， T_R30和对照处理细菌的菌落组成相似度较高，共性最大。利用PICRUSt软件对细菌群落功能组成进行预测，发现各处理土壤样本的主要COG功能组成较为相似，但各COG相对丰度有所差异。综上所述，液态有机肥不同比例替代化学冲施肥能增加外源细菌种类，改变丰富度、多样性和菌落组成，以替代30%比例时效果最佳，为液态有机肥与化学冲施肥配施提供了理论依据。

关键词: 设施番茄, 液态有机肥, 化学冲施肥, 细菌, 群落结构