RESEARCH
We investigate the major physiological innovations that allowed plants to survive on land and colonize increasingly arid environments.
We make use of ecological and evolutionary diversity to answer fundamental questions related to the roles of stomatal regulation, abscisic acid, and xylem physiology in driving land plant tolerance to water deficit.
Featured Research
Abscisic acid (ABA) is a plant hormone that is synthesized when cells lose turgor. In seed plants, it plays a critical role in closing stomata under conditions of water stress. At the same time, ABA initiates drought responses in other systems, facilitating a coordinated physiological reaction. ABA also performs unrelated functions ranging from sex determination in fern gametophytes to the initiation of leaf senescence. Our group is pursuing several projects focused on the evolution of ABA's diverse functions. Image shows chemical structure of abscisic acid. 
Abscisic acid (ABA) is a plant hormone that is synthesized when cells lose turgor. In seed plants, it plays a critical role in closing stomata under conditions of water stress. At the same time, ABA initiates drought responses in other systems, facilitating a coordinated physiological reaction. ABA also performs unrelated functions ranging from sex determination in fern gametophytes to the initiation of leaf senescence. Our group is pursuing several projects focused on the evolution of ABA's diverse functions. Image shows chemical structure of abscisic acid. 
Xylem, the tissue responsible for transporting water and dissolved nutrients, appeared early in the history of land plants and (with phloem) serves as the defining characteristic of all vascular plants. However, vascular plants show dramatic differences in the amount, arrangement, and architecture of their xylem. We are investigating the nature of these differences and their effects on hydraulic conductivity, water use efficiency, and drought tolerance. Image shows xylem of Phellodendron amurense.