Abstract
Shade from neighboring plants limits light for photosynthesis; as a consequence, plants have a variety of strategies to avoid canopy shade and compete with their neighbors for light. Collectively the response to foliar shade is called the shade avoidance syndrome (SAS). The SAS includes elongation of a variety of organs, acceleration of flowering time, and additional physiological responses, which are seen throughout the plant life cycle. However, current mechanistic knowledge is mainly limited to shade-induced elongation of seedlings. Here we use phenotypic profiling of seedling, leaf, and flowering time traits to untangle complex SAS networks. We used over-representation analysis (ORA) of shade-responsive genes, combined with previous annotation, to logically select 59 known and candidate novel mutants for phenotyping. Our analysis reveals shared and separate pathways for each shade avoidance response. In particular, auxin pathway components were required for shade avoidance responses in hypocotyl, petiole, and flowering time, whereas jasmonic acid pathway components were only required for petiole and flowering time responses. Our phenotypic profiling allowed discovery of seventeen novel shade avoidance mutants. Our results demonstrate that logical selection of mutants increased success of phenotypic profiling to dissect complex traits and discover novel components.
Highlights
Plant canopy shade limits available light for photosynthesis
We compared gene expression in samples treated with simulated shade for 1 hour or 4 hours to untreated control samples (R/FR = 1.9 and 80–100 μE photosynthetically active radiation (PAR)) and found a total of 164 and 97 genes to be differentially expressed (FDR
We previously found that MIDA9 is induced by PIF4 and/or PIF5 during hypocotyl growing phase [78], suggesting that MIDA9 is involved in growth-control networks
Summary
Plant canopy shade limits available light for photosynthesis. Because plants are sessile, this presents a particular challenge. Perhaps as a consequence plants developed a light-quality sensory system for canopy shade; perception of foiliar shade and/or reflection from neighbor plants (“neighbor detection”) can induce the shade avoidance syndrome (SAS) is collection of responses to canopy shade in plants. Shade induces upward leaf movement, accelerates flowering time (the developmental transition form vegetative phase to reproductive phase), suppresses shoot branching, and alters resource allocation [1]. All of these responses can be helpful for promoting survival when there is competition for light from neighboring plants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
