Combatting environmental impacts and microbiological pollution risks in Potato cropping: Benefits of forage cultivation in a semi-arid region

Abstract

Continuous potato cropping in semi-arid regions, which are vulnerable to erosion, reduces tuber yields and leads to a decline in soil quality. This research delves into the impact of forage cultivation on soil bacterial and archaeal communities and the associated hazard-related virulence genes and antibiotic resistance genes (ARGs) within potato cropping systems. The study reveals that distinct crop rotation schemes significantly alter soil physicochemical properties. Compared to non-potato cultivation, continuous potato cropping substantially reduces soil organic carbon from 31.9 g kg ${}^{-1}$ to 15.7 g kg ${}^{-1}$ and total nitrogen from 3.7 g kg ${}^{-1}$ to 1.6 g kg ${}^{-1}$, indicating a notable deterioration in soil fertility. Among the ten identified phyla, Proteobacteria demonstrates the highest relative abundance, from 34.6% to 38.4%, closely followed by Actinobacteria, ranging from 20.5% to 36.0%. These two phyla likely play a crucial role in maintaining soil health. Moreover, continuous potato cultivation (CPC) results in more specific ARGs than non-potato cultivation (NPC). This phenomenon implies that CPC may select for particular resistance traits within the soil microbiome, potentially due to changes in the composition of the soil microbiota. Forage crops (oats or a mixture of oats and peas) exhibit varying effects on ARGs at different growth stages. The differences observed between the flowering and maturity stages of oats suggest that plant growth and the composition of root exudates can influence microbial communities and the prevalence of ARGs. The Mantel test further indicates that specific soil properties impact the abundance of certain microbial taxa and determine the expression of key functional genes, including those associated with antibiotic resistance. These findings underscore the intricate interactions among microbial communities, genes, and soil health, providing essential guidance for formulating agricultural practices to manage soil health and mitigating problems such as antibiotic resistance in continuously cropped soils.

Importantly, this study highlights the significant benefits of crop diversification, primarily through the incorporation of forage crops, in safeguarding soil health and maintaining microbial diversity within potato cropping systems. The results offer valuable perspectives for developing sustainable agricultural strategies, which can enhance soil fertility and promote ecosystem stability in semi-arid regions.