Meeting Abstract

113.5  Monday, Jan. 7  Abiotic noise in volatile signaling by plants WILSON, J.K.*; WOODS, H.A.; University of Montana keatonwilson@me.com

Plants have developed a multitude of ways to defend themselves from insect herbivores. One recently discovered strategy is the release of airborne chemicals that signal the type of herbivore attacking the plant. In some systems, this information is used by predators and parasitoids to find their prey or host – that is, the plant defends itself by calling in a third trophic-level. However, we still know little about these communication systems, and the ecological ramifications they have. Any type of communication system can be corrupted by noise. Here, we propose that variation in environmental factors can act as a source of noise in plant volatile communication systems. We focus on abiotic noise affecting the plant-transmitter, Datura wrightii after herbivory by larvae of the hawkmoth Manduca sexta based on field measurements from a population in southeastern Arizona. Among potential sources of noise in the natural world, temperature is likely to be particularly powerful, because it modifies the underlying biochemistry of signal reception and transmission, and is one of the few abiotic factors that can affect plants and insects simultaneously. However, air humidity and soil moisture vary widely (both spatially and temporally) in many habitats, including the desert southwest, and may also be important in modifying communication between plants and insect defenders. If environmental noise causes significant signal degradation, the effects of varying abiotic conditions on both transmitters (plants) and receivers (insect predators and parasitoids) may drive broad patterns of evolution and ecology in both parties.