Antibiotics and\nPesticides Enhancing the Transfer\nof Resistomes among Soil-Bayberry-Fruit Fly Food Chain in the Orchard\nEcosystem

While substantial amounts of antibiotics and pesticides\nare applied\nto maintain orchard yields, their influence on the dissemination and\nrisk of antibiotic resisitome in the orchard food chain remains poorly\nunderstood. In this study, we characterized the bacterial and fungal\ncommunities and differentiated both antibiotic resistance genes (ARGs)\nand virulence factor genes (VFGs) in the soil, Chinese bayberry (matured\nand fallen), and fruit fly gut, collected from five geographic locations.\nOur results showed that fruit fly guts and soils exhibit a higher\nabundance of ARGs and VFGs compared with bayberry fruits. We identified\n112 shared ARGs and 75 shared VFGs, with aminoglycoside and adherence\nfactor genes being among the most abundant. The co-occurrence network\nrevealed some shared microbes, such as <i>Bacillus</i> and <i>Candida</i>, as potential hosts of ARGs, highlighting the vector\nrisks for both above- and below-ground parts of the orchard food chain.\nNotably, the elevated levels of antibiotics and pesticide residues\nin orchard soils increase ARGs, mobile genetic elements (MGEs), and\nVFGs in the soil-bayberry-fruit fly food chain. Our study highlighted\nthat agricultural management, including the overuse of antibiotics\nand pesticides, could be the key factor in accumulating resistomes\nin the orchard food chain.