Toxicity and Tissue Accumulation Characteristics of the Herbicide Pendimethalin in Ginger (Zingiber Officinale Roscoe)

BackgroundEnvironmental health and food safety issues potentially caused by the dinitroaniline herbicide pendimethalin are a worldwide concern. Due to its importance for crop plants, the determination of possible toxicity and accumulation characteristics of pendimethalin in ginger should be determined. ResultsThe toxicity response of ginger and tissue accumulation effects of pendimethalin on ginger biomass were studied by utilizing pendimethalin in a dose-response study. No significant effect on ginger biomass is observed when the concentration of pendimethalin used is less than 6.7 ppm, while > 10 ppm pendimethalin significantly reduces the biomass of ginger. This is attributed to root damage. The net photosynthetic rate of ginger when treated with 16.7 ppm pendimethalin is 11.37% lower than that of the control organisms, which is mainly caused by stomatal limitation. In addition, high-dose pendimethalin (16.7 ppm) causes the accumulation of reactive oxygen species (ROS) in ginger. The activity of superoxide dismutase (SOD) and peroxidase increases accordingly, maintaining the dynamic balance of ROS content. There is no significant effect on malondialdehyde levels or on membrane permeability. Pendimethalin has no significant effect on the expression of ginger α-tubulin mRNA. The damage of high-dose (16.7 ppm) pendimethalin to ginger is mainly caused by oxidative stress. Pendimethalin is significantly accumulated in ginger roots, but not rhizomes. ConclusionsBecause of this, application of pendimethalin to treat weeds in ginger fields may not pose a threat to human health.