Evolution of cold acclimation and frost tolerance in Pooideae

The grass subfamily Pooideae dominate the grass flora in the Northern temperate region and we explore how Pooideae has evolved to cope with winter. In particular, we study cold acclimation and frost tolerance. We test phylogenetically diverse species for physiological responses to cold and frost under controlled conditions and use transcriptomics, metabolomics and studies of candidate genes to explore the molecular basis for evolution of cold acclimation and frost tolerance.

Evolution of flowering time in Pooideae

The Northern temperate region is characterized by a short, intense growing season. Timing of flowering for maximum reproductive output in this short growing season is essential. In Pooideae model species like barley and wheat, vernalization followed by long days initiate flowering in the spring. We study how the two-step induction of flowering has evolved in Pooideae. We test phylogenetically diverse Pooideae species for flowering in response to vernalization and photoperiod and use transcriptome data and candidate gene analyses to understand the molecular basis for evolution of flowering time.

Evolution of life history strategies in Pooideae

Many plants avoid seasonal stressors like drought and frost by adopting an annual life cycle strategy. An alternative strategy is to survive stressful conditions by adopting coping mechanisms to live through many seasons, referred to as the perennial life cycle strategy. Annual plants flower a single time during their one-year life cycle, investing much of their energy into rapid reproduction. In contrast, perennial plants flower multiple times over several years, and partition their resources between reproduction and persistence. These two adaptive strategies require fundamentally different physiology and growth traits. Annuals have high growth rates, large leaf area, large allocation of resources to reproductive structures and high biomass production. Perennials have traits allowing for persistence and defense, like high tissue density and allocation of higher proportion of biomass into roots. Even with these fundamental differences in growth strategies, the evolutionary distance between annual and perennial species may be very small, indicating that small differences in genetic makeup differentiate the growth habits. However, what these differences are is to a large degree unknown. We seek out to identify genes contributing to the differences between annual and perennial life history strategies in temperate grasses and determine how physiology and development are influenced by these genes.