Abstract
Plant volatile organic compound (VOC) emissions are important mediators for plant interactions with biotic and abiotic factors in the environment. Changes in VOC emissions can be caused by factors associated with climate change, such as warming and drought. However, we currently lack an understanding of how warming and drought affect plants' emissions in their natural environment, let alone how these climate factors may interact to synergistically affect emissions. To fill these knowledge gaps, we measured VOC emissions from tall goldenrod (Solidago altissima) in an early successional plant community under four climate treatments: ambient control, warmed, drought, and warmed + drought. Treatments were applied in situ using open-top chambers for warming and rainout shelters for drought. Drought treatments (drought and warmed + drought) have a stronger effect on VOC emissions compared to nondrought treatments (ambient and warmed). Furthermore, while the overall abundance of VOCs did not differ between treatments, there were specific compounds associated with one or more climate treatments. For example, diisopropyl adipate was more abundant in the drought and warmed + drought treatments. Our study shows that in goldenrod, drought may have a stronger effect than warming on VOC emissions, but moreover, that specific compounds are especially sensitive to certain climate treatments. However, additional experimentation is necessary to validate the functions associated with the affected compounds. These findings demonstrate that climate change alters chemical emissions, which in turn could have implications for ecosystem functioning via changes in plant-plant communication, plant-insect interactions, and overall plant fitness.