Because plants are rooted in place they have a remarkable ability to withstand a wide range of environmental conditions. They do so by altering their growth, development and physiology to suit their current environment. We are interested in determining the genes and mechanisms underlying this fascinating phenotypic plasticity and how the genetic pathways have changed over time to allow adaptation to different environments.
To achieve these goals we use molecular and quantitative genetics and genomics techniques coupled with bioinformatics and statistical analyses. We work with the Streptanthus species complex, Brassica rapa, Tomato, and Arabidopsis.
How do plants adapt to different climates? Plants undergo critical developmental transitions that must be matched to their local environment to enable success. For example, germination must occur when environmental conditions are favorable for seedling establishment and growth. Flowering must occur when pollinators are present and when conditions can support resource investment into seed. The proper timing for these events varies widely in different climates. Perennials growing in the foothills of California’s Sierra Nevada must cope with significant summer heat and drought and therefore often germinate in the fall, grow in the winter, and flower in the spring. This strategy does work not for plants at higher elevation where many feet of snow cover the ground from November to May or June. In collaboration with Jenny Gremer, Sharon Strauss, and Johanna Schmitt we are studying the environmental cues that plants in the Streptanthus clade use to determine germination and reproductive timing, how the use of these cues varies in populations and species adapted to different climates, and the evolution of genetic networks associated with these changes.
Biodiversity is critical for the health of ecosystems, our biosphere, and humankind. However, biodiversity is threatened by habitat loss and climate change, which has resulted in the acceleration of species extinctions across the world. The ability to predict how the genetic composition of populations impacts their long-term persistence or extinction in different and changing environments requires integrating analysis techniques and data across diverse fields. In collaboration with Jenny Gremer, Troy Magney, and Denneal Jamison, we are developing integrative demographic models that incorporate genetic, physiological, and life history traits to improve multi-generational predictions of population persistence and extinction for Streptanthus tortuosus (Mountain Jewelflower). The resulting integrative demography models will provide a road map for conservation biologists and managers to use genomic information to predict effects of different conservation strategies, such as assisted migration or introducing genetic variation, which can be applied across wild, managed, and agricultural species and populations.
Light is essential for plant growth. Perhaps as a consequence, plants have an intricate set of photoreceptors and responses that they use to optimize their development and physiology to suit their light environment. We study the downstream mechanisms underlying these responses and how plants have evolved differences in their light perception and responses that allow them to thrive in different environments. We are interested in both the genetic and molecular basis of variation in light response as well as the adaptive consequences. A combination of molecular and quantitative genetics and genomics is used in Arabidopsis, Tomato, and Brassica