Elevated temperature decreases preferences of native herbivores to an invasive plant

Abstract

<!-- named anchor --> Plant invasions threaten global ecosystems and biodiversity. Climate warming greatly challenge the management of plant invasions by affecting plant-herbivore interactions. Plant volatiles are used as signals by herbivores to mediate interactions between plants and herbivores. However, it is unclear whether climate warming will affect the volatile emissions of invasive plants, and subsequently alter the preferences of native herbivores. In this study, simulated warming experiments were conducted to investigate the preferences of a generalist moth, Spodoptera litura, and an oligophagous beetle, Cassida piperata, for the invasive plant species, Alternanthera philoxeroides, and the native species, Alternanthera sessilis. We found that elevated temperature altered the composition of the plant volatile emissions. Elevated temperature did not alter the behavioral preferences of S. litura and C. piperata to the invasive plant A. philoxeroides. However, elevated temperature indirectly increased the oviposition preference of the generalist moth to the native plant compared with the invasive plant. These results suggest that global warming might shift the oviposition preference of the generalist moth S. litura from an invasive plant to a native one, thereby potentially increasing damage to the native plants. These results are important for predicting alien plant invasions under future global warming scenarios.