Multi-walled Carbon Nanotubes Remediate the Phytotoxicity of Quinclorac to Tomato

In order to remediate the phytotoxicity of quinclorac to tomato by multi-walled carbon nanotubes (MWCNTs), the adsorption of quinclorac to MWCNTs was monitored and the effect of MWCNTs on the phytotoxicity of quinclorac to tomato in soil were studied. The results showed that the Linear equation and Freundlich equation can well fit the adsorption isotherm of quinclorac in the soil containing MWCNTs. The adsorption of quinclorac in soil was significantly enhanced by the addition of MWCNTs; the K_d of soil (1% MWCNTs) was 28.7 times of pure soil. The quinclorac had an obvious inhibitory effect on the growth of tomatoes; serious phytotoxicity was also induced even at the lowest concentration of 0.025 mg/kg. With the MWCNTs content in soil increased to 0.5% and 1%, the phytotoxicity of quinclorac to tomatoes decreased significantly, and the height and fresh weight of tomatoes were even higher than those of the control group, indicating that MWCNTs can promote the growth of tomato. These results provide a reference for resolving the problem of phytotoxicity induced by residual herbicides in farmland.