Quinclorac-induced cell death is accompanied by generation of reactive oxygen species in maize root tissue

Quinclorac, an auxinic herbicide, has a mode of action thought to be similar to other auxins such as 2,4-D. It exhibits high selectivity among grass species and the primary mechanism of its specific action has been considered to be the selective induction of ethylene biosynthesis, which ultimately leads to cyanide accumulation in susceptible grasses. Here, we report results suggesting that quinclorac may have a different action from 2,4-D; quinclorac-induced cell death in maize roots may be caused by ROS, but not by ethylene as well as its biosynthetic pathway-related substances including cyanide.