Reduced host plant growth and increased tyrosine-derived secondary metabolites under climate change and negative consequences on its specialist herbivore

摘要

Compositive changes in climatic factors, e.g., carbon dioxide (CO_2) and precipitation frequency and intensity, affect the strength of species interactions via responses in plants. Therefore, understanding the effects of climate change on plant-herbivore interactions is important to maintain biodiversity as about 70% of insects are herbivorous. However, the interactive effects of CO_2 and precipitation on plants and consequences for herbivores are poorly understood. Here, we examined how elevated CO_2 and increased watering frequency affect the growth and resistance responses of Aristolochia contorta and the growth performance of its specialist herbivore, Sericinus montela. Elevated CO_2 suppressed growth with decreased photosynthesis ability, and increased resistance in plants. In contrast, increased watering frequency partly ameliorated the negative effects of high CO_2. Growth performance of specialist herbivores decreased under elevated CO_2 condition as a consequence of increased resistance in plants. Due to the significant effects of CO_2, we suggest that both the quantity and the quality of host plants as a food would decline, and the growth performance of its specialist herbivore might be threatened as climate change progresses.