Laboratory-Simulated Inhibitory Effects of the Floating-Bed Plants on and Their Microbial Communities' Responses to Microcystins.

Three common floating bed plants, , , and , were selected in the present study to investigate their inhibitory effects on toxic . The results showed that all three types of floating-bed plants could considerably inhibit the growth of and effectively remove the microcystins (MCs) from water systems, among which, and were more effective in resisting , and the removal rate of the intracellular MCs could be up to 100%. In addition, the roots and leaves of the three plants were enriched with a large number of MCs and demonstrated significant antioxidant responses, as evidenced by the increase in the content of catalase (CAT), glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), and malondialdehyde (MDA) in the roots, stems, and leaves of the plants. Furthermore, this study also showed that Proteobacteria, Bacteroidota, Myxococcota, Verrucomicrobiota, and Actinobacteriota dominated the root microorganisms of the three plants. Moreover, a variety of MC-degrading bacteria, including , , , and , were found at the genus level, which further provides important basic data for the regulation of eutrophic water bodies and the removal of MCs.