Drought and Beetle induced Monoterpene Defenses in Pinyon Pine Seedlings

Franklin Alongi, Danielle Ulrich, Department of Ecology, Montana State University Bozeman, Culbertson Hall, 100, Bozeman, MT 59717

In 2002, drought led to a mass mortality event in pinyon pine (Pinus edulis) across four Southwestern US states, leading to the loss of an estimated 350 million trees. With a changing climate, droughts such as these are expected to become more frequent and more severe. On top of drought stress, weakened pinyon pine trees are also targeted by bark beetles. Many mechanisms exist for plant defense. Resin produced by a tree can effectively "pitch out" attacking beetles, as well as expose them to chemical defenses. Some tree species have been shown to detect defense compounds of a neighboring tree, allowing for a tree to prime its defenses before it is attacked itself. Aditionally, some pine species have been shown to directly detect an herbivore by the herbivore's volatile emissions, allowing the tree to prepare for an attack. These mechanisms have not yet been tested in pinyon pine, and the ability for plants that have these chemical detection mechanisms to function under drought stress is largely unknown. In a greenhouse experiment, we subjected pinyon pine seedlings to drought, chemical defense compounds, and beetle pheromones. We measured defense volatile emissions in order to experimentally determine if pinyon exhibits these chemical detection mechanisms, as well as to determine if drought stress limits any such ability. The results of this experiment will be discussed within the overall context of plant defense mechanisms and the future of pinyon pine in the face of a changing climate.

Additional Abstract Information

Presenter: Franklin Alongi

Institution: Montana State University Bozeman

Type: Oral

Subject: Plant Sciences

Status: Approved

Time and Location

Session: Oral 1
Date/Time: Mon 1:30pm-2:30pm
Session Number: 143
List other presenters in this same room and session