Characterization of cucumber rhizosphere bacterial community with high-throughput amplicon sequencing

Controlling microbial contamination of drinking water is critical to public health. However, understanding of the microbial ecology of drinking water remains incomplete. Representing the first application of high-throughput sequencing in drinking water microbiology, the objective of this study is to evaluate pyrosequencing as a high-throughput technique for the characterization of bacterial diversity in drinking water in comparison with conventional clone library analysis. Pyrosequencing and clone library analysis were performed in parallel to study the bacterial community composition in drinking water samples following the concentration of microbial biomass in drinking water with ultrafiltration. Validated by clone library analysis, pyrosequencing was confirmed as a highly efficient deep-sequencing technique to characterize the bacterial diversity in drinking water. Sequences of Alphaproteobacteria and Betaproteobacteria dominated the bacterial community in drinking water with Oxalobacteraceae and Methylobacteriaceae as the most abundant bacterial families, which is consistent with the prominent abundance of these populations frequently detected in various freshwater environments where source waters originate. Bacterial populations represented by the most abundant sequences in drinking water were closely related to cultures of metabolically versatile bacterial taxa widely distributed in the environment, suggesting a potential link between environmental distribution, metabolic characteristics, and abundance in drinking water.

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Effects of Mancozeb on Citrus Rhizosphere Bacterial Community

10.20944/preprints202003.0115.v1 ◽

2020 ◽

Author(s):

Zhendong Huang ◽

Peng Wang ◽

Zhanxu Pu ◽

Lianming Lu ◽

Guoqing Chen ◽

...

Keyword(s):

Bacterial Community ◽

Bacterial Species ◽

Soil Health ◽

Chemical Properties ◽

Amplicon Sequencing ◽

Citrus Unshiu ◽

Comparative Experiment ◽

Asian Countries ◽

Rhizosphere Bacterial Community ◽

Bacterial Groups

Mancozeb is extensively used fungicide to prevent citrus melanose in most Asian countries, especially in China. So far, however, there have been no reports of thet effect of Mancozeb on the citrus rhizosphere bacterial community. Therefore, this comparative experiment defined the genomic and functional related to community and soil health of 2-years old Citrus unshiu Marc. rhizosphere through amplicon sequencing and chemical analysis. This study evaluated the effect of mancozeb on the chemical properties of citrus-cultivated soil and the richness and diversity of rhizosphere bacterial community. We also investigated the abundance response of rhizosphere bacterial groups to 0, 2, 4, 6 and 8 times application of 2 g mancozeb (active ingredient content, ai.) 600 times diluted with water. Our data revealed that the abundance of rhizosphere-associated bacterial species increased significantly after planting citrus. The relative abundance of Candidatus, Saccharibacteria, Parcubacteria, and Proteobacteria increased with the increase in mancozeb watering times. Meanwhile, the abundance of Nitrospirae decreased with the increase in mancozeb application times. The findings indicated that the chemical properties of the soil and the richness and diversity of rhizosphere bacterial community did not significantly differ across the mancozeb gradients in soil.

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