UCLA

The leaf surface is the locus of a multitude of physiological processes important in determining plant performance including responses to the environment. In my dissertation research, I identified specific adaptive and functional roles and constraints on stomata and trichomes. My approach utilized physiological experiments on diverse species native to California with potential applications toward understanding and improving plant drought tolerance. First, I clarified the mechanistic basis for leaf level drought response and the regulatory factors by which a stomatal safety-efficiency trade-off arises across diverse woody angiosperms. Second, I quantified foliar water uptake across diverse pairs of native California tree, shrub, and vine species with contrasting trichome densities adapted to a wide range of aridity. Lastly, I tested whether trichome presence was associated with differences in light-saturated gas exchange, water use efficiency, and climatic variables across diverse California species. This work highlighted underlying factors influencing water relations and gas exchange, including constraints on stomatal function and the key role of leaf trichomes, providing a clearer picture of the importance of these structures in species evolution and ecology.