The proper timing of flowering is key to the reproductive success of plants. Therefore it is not surprising that flowering time is highly regulated by both environmental and internal signals. One environmental signal that can accelerate flowering is shade provided neighboring plants. Plants detect shade as a shift in the ratio of red light to far-red light. Because leaves absorb more red light than far-red light, plants growing under a canopy experience light that is enriched in far-red light. The overarching goal of this project is to determine, at the molecular level, how plants perceive and respond to far-red enriched light. The project will employ genetic, physiological, and biochemical approaches to explore the impact of light quality on the genes and proteins that regulate flowering, identify novel components required for the acceleration of flowering by far-red-enriched light, and integrate plant hormones into the pathways that regulate flowering time in response to light quality. This project will also provide training and research experiences at the undergraduate, graduate, and postdoctoral levels. Because many flowering time pathways are highly conserved, it is expected that the knowledge gained in this study will be broadly applicable to higher plants. The molecular circuitry elucidated by this study will facilitate the study and manipulation of light responses in agricultural plants. For example, increasing plant density is a primary avenue to increasing crop yield. Because crowded plants shade one another, however, they experience far-red enriched light that can lead to yield-reducing precocious flowering. A better understanding of plant responses to light quality will allow for the manipulation of these traits, so that plants can be grown at higher density while minimizing undesirable consequences.
