Molecular and Physiological regulation of plant responses to neighbours.
Plants display pronounced phenotypic plasticity to a wide array of environmental stimuli and with my research group I focus primarily on the mechanistic processes that underpin shoot phenotypic plasticity.
A well-known example is a suite of growth responses to proximate neighbours, called shade avoidance, which include enhanced shoot elongation and upward leaf movement in response to far-red light reflection by neighbours (see picture below for tobacco). These responses enable plants to avoid shading by neighbouring plants, thereby increasing fitness in high-density vegetations. Similar elongation responses can be observed during submergence of flood-tolerant plants.
Shade avoidance in cultivated tobacco
Alternatively, species from shaded forest understories (see e.g. picture below) canot outgrow the giant trees around them an have evolved ways to tolerate low light conditions, including the suppression of shade avoidance responses; a wasteful investement when not returned with benefits of enahnced light interception.
Forest understory Vancouver Island, Canada.
I am studying regulatory pathways leading to shade avoidance responses, primarily in Arabidopsis, togther with a number of PhD students (Paulien Gankema, Debatosh Das, Lot Gommers, Chrysa Pantazopoulou, Franca Bongers (collaboration with Niels Anten and Jochem Evers) and Chiakai Kang) and post-doc Kate St. Onge. This work includes plant-plant interactions in Arabidopsis canopies, light signaling, plant volatiles, hormone interactions and gene expression patterns leading to regulation of cell growth. The image below depicts a simplified version of our current understanding of light-mediated nieghbor detection and signaling events
Illustration of light-mediated signaling events in response to neighbor proximity. Image taken from Gommers et al. (2013) Trends in Plant Science 18: 65-71.
Suppression of shade avoidance responses is studied with PhD student Lot Gommers and is the central them of the soon to be started VIDI project.
I have an additional interest in multiple stress resistance and work on projects studying crosstalk between competition and defense against pathogens and herbivores (with recently graduated PhD students Wouter Kegge and Mieke de Wit), as well as on signalling convergence between shade avoidance and submergence escape (postdoc project Kate St. Onge).
This work is supported by various grants from the Netherlands Organisation for Scientific Research NWO-ALW (including VENI (2007-2010), VIDI (acquired in 2013), open competition (2007, 2014) and Ecogenomics (2011-2014) grants) and Utrecht University Focus and Mass investments.