Chromium-Induced Modulations in the Rhizosphere Fungal Community and Arbuscular Mycorrhizal Colonisation in Amaranthus viridis Roots

Abstract

Chromium (Cr) contamination is a significant threat to sustainable agriculture worldwide. Among different approaches to inhibit Cr contamination in soil, recently fungi have demonstrated their ability to combat the challenges of heavy metal-contaminated soils, while also enhancing crop growth. This study aims to investigate the fungal populations induced by Cr contamination, which could help alleviate Cr stress and promote plant growth and yield under unfavourable circumstances. The current study investigates the growth of Amaranthus crops under three distinct contaminated regimes: Cr stress in microbe-rich soil (MRS), Cr stress in microbe-free soil (MFS) and a control group. The findings emphasise the significant influence of Arbuscular mycorrhizal (AM) fungi to enhance both growth (by 40%) and biomass production (by 32.8%) while simultaneously reducing Cr translocation and accumulation (by 55%) in shoot tissues. The evaluation of soil microbiome dynamics reveals the sensitivity of the phyla Olpidiomycota and Chytridiomycota to Cr contamination. However, AM fungi and other potential fungal phyla can counteract Cr toxicity, thus ameliorating its adverse effects on Amaranthus. AM endophytes and other fungi in the rhizosphere can increase the yield of Amaranthus even in Cr-contaminated environments.