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Abstract Soil contamination with antibiotics and antibiotic resistant bacteria/genes (ARB/ARGs) has becoming an emerging environmental problem. Moreover, the mixed pollutants' transfer and accumulation from soil to tuberous vegetables has posed a great threat against food security and human health. In this work, the application of two absorbing materials (maize biochar and sulfate modified eggshell) was able to reduce the poisonous effect of soil antibiotics on potato root system by stimulate the dissipation of water-soluble antibiotics in soil; and also improve food quality by increasing potato starch, protein, fat, and vitamins. Meanwhile, both amendments could effectively decrease the classes and the accumulative abundance of ARB and ARGs (sul I, sul II, cat I, cat II, erm A, erm B) in the edible parts of potato. The lowest abundance of ARGs was detected in the biochar application treatment, with the accumulative ARG level of 8.9 × 102 and 7.2 × 102 copies mL−1 in potato peel (sul l + cat I + erm A) and tuberous root (sul I), respectively. It is the first study to demonstrate the feasibility of biochar and eggshell derived from agricultural wastes as green absorbing materials to reduce soil antibiotic, ARB, and ARGs accumulation risk in tuberous vegetable. Graphical abstract Image 1 Highlights • Biochar or eggshell impeded soil antibiotics accumulation in potato effectively. • ARB isolates in potato decreased significantly after biochar or eggshell addition. • ARG accumulation risk was limited in potato with biochar or eggshell amendment. • Impedance effect of biochar was more effective than that of eggshell. • Biochar or eggshell application provided new strategy to ensure vegetable security. ARB and ARG accumulation risk was limited in potato with biochar or eggshell amendment; Impedance effect of biochar was more effective than that of eggshell. [ABSTRACT FROM AUTHOR]

High abundances of antibiotic-resistant pathogenic bacteria (ARPB) and antibiotic resistance genes (ARGs) in agricultural soil-plant systems have become serious threats to human health and environmental safety. Therefore, it is crucial to develop targeted technology to control existing antibiotic resistance (AR) contamination and potential dissemination in soil-plant systems. In this work, polyvalent bacteriophage (phage) therapy and biochar amendment were applied separately and in combination to stimulate ARPB/ARG dissipation in a soil-lettuce system. With combined application of biochar and polyvalent phage, the abundance of Escherichia coli K-12 (tet R ) and Pseudomonas aeruginosa PAO1 (amp R + fos R ) and their corresponding ARGs ( tet M, tet Q, tet W, amp C, and fos A) significantly decreased in the soil after 63 days' incubation ( p  < 0.05). Similar results for endophytic K-12 and PAO1, and ARGs, were also obtained in lettuce tissues following combined treatment. Additionally, high throughput sequencing revealed that biochar and polyvalent phage synergetically improved the structural diversity and functional stability of the indigenous bacterial communities in soil and the endophytic ones in lettuce. Hence, this work proposes a novel biotechnology that combines biochar amendment and polyvalent phage therapy to achieve targeted inactivation of ARPB, which stimulates ARG dissipation in soil-lettuce systems. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Biochar impeded the vertical migration of ARPB from top soil to lower soil. • Polyvalent phage targeted inactivation of ARPB along different soil layers. • Biochar amendment with phage therapy synergistically eliminated ARG risk. • Combined treatment maintained the diversity of the bacteria community. Abstract The vertical migration of antibiotic resistance pathogenic bacteria (ARPB) and antibiotic resistance genes (ARGs) in the surface soil-vadose soil system has become a new threat to ecological safety and public health; there is an imperative need to develop an efficient technique for targeted control and inactivation of ARPB in these systems. In this work, undisturbed soil columns (0 ∼ −5 m) were constructed to investigate the impact of biochar amendment or/and polyvalent bacteriophage (ΦYSZ-KK) therapy on the vertical control and inactivation of tetracycline-resistant Escherichia coli K-12 and chloramphenicol-resistant Klebsiella pneumonia K-6. The simultaneous application of polyvalent phage and biochar impeded the vertical migration of ARPB from the top soil to lower soil layers and stimulated the ARPB dissipation in the soil column. After 60-day incubation, levels of ARPB and ARGs decreased significantly in the soil column by magnitudes of 2-6. Additionally, high throughput sequencing indicated that the simultaneous application of biochar and phage clearly maintained the structure and diversity of the soil microbial communities (p < 0.05). This work therefore demonstrates that the application of a biochar/phage combination is an environmentally friendly, efficacious measure for the control and inactivation of ARPB/ARGs in vertical soil column systems. [ABSTRACT FROM AUTHOR]