# Migration Characteristics of Manure-Derived Antibiotic-Resistant Bacteria in Vegetables Under Different Soil Types

## TL;DR

This study shows how manure containing antibiotics affects the spread of antibiotic-resistant bacteria in vegetables, depending on soil type.

## Contribution

The study reveals how soil type influences the migration and proliferation of antibiotic-resistant bacteria from manure to vegetables.

## Key findings

- CTC-manure application increased CTC-resistant endophytic bacteria most in black soil (235.43%)
- CTC promoted the growth of potential pathogens like Klebsiella and Rhodococcus in soil-vegetable systems
- Soil properties like nitrogen and phosphorus significantly shaped the CREB community structure

## Abstract

The application of livestock manure can introduce antibiotic-resistant bacteria (ARB) into soil–vegetable systems, potentially shaping the antibiotic resistance profiles of plants. This study investigated the effects of manure containing chlortetracycline (CTC) on antibiotic resistance in pakchoi grown in three distinct soil types (black soil, fluvo-aquic soil, and red soil). The results demonstrated that CTC-manure application significantly increased the relative abundance of CTC-resistant endophytic bacteria (CREB), with the magnitude of the increase following the order: black soil (235.43%) > fluvo-aquic soil (64.5%) > red soil (10.68%). Furthermore, the presence of CTC promoted the proliferation of Acinetobacter and increased the abundance of potential pathogens (such as Klebsiella, Rhodococcus, and Corynebacterium), thereby elevating the risk of antibiotic resistance transmission. Metabolomic analysis revealed that CTC induced the most substantial metabolic alterations in pakchoi grown in red soil. Correlation analysis indicated that the CREB community structure was primarily shaped by soil properties, including total nitrogen, total phosphorus, and organic matter, and was significantly correlated with indigenous soil ARB (Pseudomonas, Bacillus, and Stenotrophomonas). This study elucidates the mechanisms underlying manure-driven antibiotic resistance dissemination in vegetable production systems and offers a theoretical foundation for developing agricultural practices to mitigate associated risks.