摘要

       粪肥和化肥都广泛应用于现代农业。然而，不同肥料对耕地土壤细菌群落结构和抗生素抗性基因（ARGs）的影响仍不清楚。本研究采用高通量测序和定量 PCR 技术，研究了化肥、猪粪和稻草灰等不同肥料施用对细菌群落结构、ARGs 和移动遗传元件 (MGEs) 的影响。结果表明，施肥可显着改变土壤细菌群落，放线菌门下盖氏菌的丰度从未施肥土壤的12.9%显着降低至施肥土壤的4.1%～7.4%（P < 0.05）。还发现施用粪肥会对土壤抗性组成产生短暂影响，ARGs 的相对丰度从 7.37 ppm 增加到 32.10 ppm。粪便施肥后氨基糖苷类、磺胺类和四环素类抗性基因的丰度大幅增加，然后随着一些携带ARGs的肠道细菌的腐烂逐渐恢复到正常水平。相比之下，化肥和秸秆灰的施用显着改变了细菌群落结构，但对土壤抗性组影响不大。总体而言，本研究结果说明了不同肥料对土壤抗性组的不同影响，表明施肥引起的土壤抗性组变化主要来自细菌群落的改变，而非基因水平转移。

       Both manure and chemical fertilizers are widely used in modern agriculture. However, the impacts of different fertilizers on bacterial community structure and antibiotic resistance genes (ARGs) in arable soils still remain unclear. In this study, high-throughput sequencing and quantitative PCR were employed to investigate the bacterial community structure, ARGs and mobile genetic elements (MGEs) influenced by the application of different fertilizers, including chemical fertilizers, piggery manure and straw ash. The results showed that the application of fertilizers could significantly change the soil bacterial community and the abundance of Gaiella under phylum Actinobacteria was significantly reduced from 12.9% in unfertilized soil to 4.1%–7.4% in fertilized soil (P < 0.05). It was also found that the application of manure could cause a transient effect on soil resistome composition and the relative abundance of ARGs increased from 7.37 ppm to 32.10 ppm. The abundance of aminoglycoside, sulfonamide and tetracycline resistance genes greatly increased after manure fertilization and then gradually returned to normal levels with the decay of some intestinal bacteria carrying ARGs. In contrast, the application of chemical fertilizers and straw ash significantly changed the bacterial community structure but exerted little effect on soil resistome. Overall, the results of this study illustrated the different effects of different fertilizers on the soil resistome and revealed that the changes of soil resistome induced by manure application mainly resulted from alteration of bacteria community rather than the horizontal gene transfer.
https://www.sciencedirect.com/science/article/abs/pii/S0045653517313693