The threat of the fall armyworm to Asian rice production amplified by the brown planthopper

There is concern in Asia that the recently invaded fall armyworm (FAW), a major pest of maize, may adapt to feed on rice. We found that the brown plant hopper (BPH) may contribute to this risk. BPH-infested rice plants strongly attracted FAW moths to oviposition on rice plants. Although FAW caterpillars developed relatively poorly on rice, they did survive on young rice plants and readily pupated in exceedingly moist soils, typical for rice cultivation. The enhanced attractiveness of rice caused by BPH may facilitate FAW to quickly adapt to rice. Our findings reveal a new host range expansion mechanism for invasive herbivorous insects and reveal a need for monitoring and protection strategies in rice cultivation areas where BPH occurs.