Environmental microbes alleviate antibiotic disturbance on plant endophytes in aquatic microcosms: Prospects for conferring fitness benefits.

Antibiotic pollution in water environment is an emerging threat to plant health. Developing efficient strategies to reassemble the antibiotic-tolerating endophytes will confer fitness benefits on host plants to alleviate antibiotic stress. Here, introducing environmental microbes was proved as a promising approach to reshape the antibiotic-tolerating plant endophytes under antibiotic stress in aquatic microcosms. The introduction of environmental microbes effectively relieved antibiotic-driven perturbation on plant endophytes, with reduced changes in bacterial diversity and differential bacterial taxa and functional genes. Moreover, introducing environmental microbes facilitated the enrichment of endophytic bacterial genera and functional genes related to drug metabolism, which possessed the potentials to degrade antibiotics. In addition, environmental microbes boosted antibiotic-reshaped endophytes to form more stable bacterial networks for stronger antibiotic tolerance. In consequence, the decreased growth inhibition of antibiotics on host plants and enhanced antibiotic removal from microcosms were achieved by introducing environmental microbes. These findings pursue environmental microbes as practical resources to assist plants in reshaping the stress-alleviating endophytes, potentially improving plant tolerance to water pollution.

Unmasking Spatial Heterogeneity in Phytotoxicology Mechanisms Induced by Carbamazepine by Mass Spectrometry Imaging and Multiomics Analyses.

Previous studies have highlighted the toxicity of pharmaceuticals and personal care products (PPCPs) in plants, yet understanding their spatial distribution within plant tissues and specific toxic effects remains limited. This study investigates the spatial-specific toxic effects of carbamazepine (CBZ), a prevalent PPCP, in plants. Utilizing desorption electrospray ionization mass spectrometry imaging (DESI-MSI), CBZ and its transformation products were observed predominantly at the leaf edges, with 2.3-fold higher concentrations than inner regions, which was confirmed by LC-MS. Transcriptomic and metabolic analyses revealed significant differences in gene expression and metabolite levels between the inner and outer leaf regions, emphasizing the spatial location's role in CBZ response. Notably, photosynthesis-related genes were markedly downregulated, and photosynthetic efficiency was reduced at leaf edges. Additionally, elevated oxidative stress at leaf edges was indicated by higher antioxidant enzyme activity, cell membrane impairment, and increased free fatty acids. Given the increased oxidative stress at the leaf margins, the study suggests using in situ Raman spectroscopy for early detection of CBZ-induced damage by monitoring reactive oxygen species levels. These findings provide crucial insights into the spatial toxicological mechanisms of CBZ in plants, forming a basis for future spatial toxicology research of PPCPs.