Antibiotic resistance genes in soils: Is their transfer to plants possible?

Abstract

Soil is a major reservoir of resistance genes for antibiotics (ARGs) such as tetracycline, streptomycin and ciprofloxacin. The spread of ARGs in soils is mainly attributed to intensive livestock farming and agricultural practices. In particular, the application of manures to soil is one of the most important pathways for the entry of ARGs into agricultural soils. While the diversity and abundance of ARGs in soils have been extensively studied, little is known about their subsequent transmission to the plant microbiome. The ARGs coud be transferred from amended soils to plants through colonisation of plnat tissues by foliar or root endophytic bacteria or by attachment of ARG-bearing bacteria to plant surfaces. The main objective of this work is to gather information on the possible transfer of ARGs to plants in order to understand the magnitude of the problem, as it may jeopardise food safety and, consequently, human health.