Overview of Research

Animals can choose fight or flight in response to danger, but plants are rooted in place. This film explores the fascinating behavior of plants as they respond to their environment. For example, the wild coyote tobacco Nicotiana attenuata responds specifically to its attackers depending on who they are -- and how dangerous! The tobacco plant's most famous toxin, nicotine, poisons some attackers, but not others. Ian Baldwin of the Max Planck Institute for Chemical Ecology and his team discovered that when a nicotine-tolerant tobacco hornworm starts chewing on this tobacco's leaves, the plant releases a smelly SOS which attracts the caterpillar's enemies. Other plants can eavesdrop on this SOS smell, and might use it to ramp up their own defenses. These are just a few of the tactics regularly employed by wiley plants fighting to survive and reproduce.

Our goal is to understand how plants survive in nature. Few agricultural plants can survive even a single growing season without being pampered with fertilizers, water, and protection from competitors, pathogens and herbivores. Humans have bred agricultural plants to do amazing things, to produce more food for us which their wild ancestors didn’t. In doing so, they have become environmentally “challenged”. Survival in the real world requires complex traits that quantitatively adjust a plant’s metabolism to meet the demands of growth, defense and reproduction required for plants to maximize their production of grandchildren and thereby their Darwinian fitness. Surprisingly, we know very little about the genes that make this possible. There are two types of explanations for this deficit in our knowledge: tools and student training.

While many of the technology platforms (HTP sequencing, transcriptomics, metabolomics and proteomics) that have fueled the molecular biology revolution are readily transferred among taxa, the tools required for the manipulation of gene expression (stable and transient transformation) are not, and tend to be highly species-, and sometimes even cultivar-specific. Thanks to the long-term funding from the Max Planck Society, we have built molecular toolboxes for two native plant species and some of their herbivores which we selected, based on their natural histories, to learn about traits that are needed for survival in the primordial agricultural niche. We have developed rapid and efficient transformation systems for both species based on Agrobacterium-based protocols and we use constructs based on the Tobacco Rattle Virus to activate virus induced gene silencing. The two plant species and their associated ecosystems are the "ecological expression systems" for the group, systems in which we pursue our questions to understand the genetic basis for ecological sophistication:

Nicotiana attenuata, an annual native tobacco found in the Great Basin Desert of Southwestern USA, occurs ephemerally in large populations after fires and germinates from long-lived seed banks in response to germination cues in wood smoke. As a consequence of this particular germination behavior, N. attenuata chases fires in ecological time and has evolved to grow in habitats that share most of the same selection pressures that agricultural plants face in the agricultural niche: a large unpredictable herbivore community, strong intra-specific competition, and selection for rapid growth in the nitrogen-rich soils that occur immediately after fires. This selection for rapid, synchronized growth has in turn selected for strong growth-defense tradeoffs as the plants adjust their phenotypes to the environment they find themselves in. Solanum nigrum is a panartic weed of agricultural fields with its own community of herbivores.

We study both species at our field stations, located at the Brigham Young University’s Lytle Ranch Preserve in SW Utah and the Walnut Creek Centre for Education and Research (WCCER), just outside Prescott in Arizona. These field stations play a central role in our research: most of our research questions originate from field observations and end with experimental tests carried out with transformed plants in both field stations.

To facilitate the training of genome-enabled field biologists, three engineers and 5 technicians provide access to and support in the use of molecular, analytical and ecological tools that enable early-stage scientists to use these platforms to dissect and manipulate ecologically important traits under real-world conditions, without having to devote their entire PhD training to develop these technologies. For more information see the feature article in Nature: Growth Industry by Alison Abbott.