The Genetic Basis of Plant Ecophysiology

We are particularly interested in an important parameter called Water Use Efficiency (WUE), which reflects the balance between CO2 assimilation and water use. We identified a natural genetic variant affecting WUE using a combination of high-throughput phenotyping, population genetics, linkage mapping, and transgenics in Arabidopsis thaliana (Des Marais et al. 2014. PNAS). Follow-up research demonstrates that the seemingly deleterious MPK12 allele experiences a selective advantage when grown with competitors — likely because the allele causes plants to be greedy with water use — though it suffers a fitness penalty when water is limiting (Campitelli, Des Marais, & Juenger, 2016. Ecol Letters). We are currently studying WUE in the model grass species, Brachypodium distachyon (Des Marais et al. 2016. Plant Sci).