Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, 266101, P.R. China.
Kunming Tobacco Company, Kunming, 651500, P.R. China.
Sci Rep. 2020 May 29;10(1):8804. doi: 10.1038/s41598-020-65203-w.
To evaluate the micro-ecological effects of tetracycline residues on tobacco soil, high-throughput sequencing technology was used to study the effects of the addition of different concentrations (0, 5, 50, and 500 mg·kg) of tetracycline on the abundance, diversity, and structure of bacterial and fungal communities in the rhizosphere and non-rhizosphere soil of flue-cured tobacco in China. Results showed that the presence of tetracycline had an important but varying effect on soil bacterial and fungal community richness, diversity, and structure. Changes in the diversity indices (Chao index and Shannon index) of soil bacterial and fungal communities showed a similar pattern after the addition of tetracycline; however, a few differences were found in the effects of tetracycline in the rhizosphere and non-rhizosphere soil, suggesting an evident rhizosphere-specific effect. The bacterial community at the phylum level in the rhizosphere closely clustered into one group, which might be the result of tobacco root secretions and rhizodeposition. Tetracycline showed a concentration-dependent effect on the soil bacterial community structure. The soil bacterial community structures observed after treatments with higher concentrations of tetracycline (50 and 500 mg·kg) were found to be closely related. Moreover, the effects of the treatments with higher concentrations of tetracycline, on the soil bacterial community at the phylum level, were different from those with lower concentrations of tetracycline (5 mg·kg), and CK treatments. This might have resulted from the induction of increasing selective pressure with increasing antibiotic concentration. Tetracycline continued to affect the soil bacterial community throughout the experiment. Tetracycline was found to have a varying impact on the community structure of soil fungi compared to that of soil bacteria, and the addition of an intermediate concentration of tetracycline (50 mg·kg) significantly increased the soil fungal diversity in the non-rhizosphere soil. The biological effects of tetracycline on the soil fungal community and the fungal-bacterial interactions, therefore, require further elucidation, warranting further research.
为了评估四环素残留对烟草土的微生态影响，本研究采用高通量测序技术，研究了不同浓度（0、5、50 和 500mg·kg）的四环素添加对中国烤烟根际和非根际土壤细菌和真菌群落丰度、多样性和结构的影响。结果表明，四环素的存在对土壤细菌和真菌群落丰富度、多样性和结构有重要但不同的影响。在添加四环素后，土壤细菌和真菌群落多样性指数（Chao 指数和 Shannon 指数）的变化模式相似，但在根际和非根际土壤中四环素的影响存在一些差异，表明存在明显的根际特异性效应。根际土壤细菌群落的门水平聚类为一个群组，这可能是烟草根系分泌物和根际分泌物的结果。四环素对土壤细菌群落结构有浓度依赖性影响。用较高浓度的四环素（50 和 500mg·kg）处理后观察到的土壤细菌群落结构彼此之间非常接近。此外，与较低浓度的四环素（5mg·kg）和 CK 处理相比，较高浓度的四环素处理对土壤细菌群落结构的影响不同。这可能是由于抗生素浓度增加导致选择性压力增加所致。四环素在整个实验过程中继续对土壤细菌群落产生影响。与土壤细菌相比，四环素对土壤真菌群落结构的影响不同，添加中间浓度的四环素（50mg·kg）显著增加了非根际土壤中土壤真菌的多样性。因此，需要进一步阐明四环素对土壤真菌群落的生物效应以及真菌-细菌相互作用，值得进一步研究。
