title: Quantitative Variation in Responses to Root Spatial Constraint within Arabidopsis thaliana.
abstract: Among the myriad of environmental stimuli that plants utilize to regulate growth and development to optimize fitness are signals obtained from various sources in the rhizosphere that give an indication of the nutrient status and volume of media available. These signals include chemical signals from other plants, nutrient signals, and thigmotropic interactions that reveal the presence of obstacles to growth. Little is known about the genetics underlying the response of plants to physical constraints present within the rhizosphere. In this study, we show that there is natural variation among Arabidopsis thaliana accessions in their growth response to physical rhizosphere constraints and competition. We mapped growth quantitative trait loci that regulate a positive response of foliar growth to short physical constraints surrounding the root. This is a highly polygenic trait and, using quantitative validation studies, we showed that natural variation in EARLY FLOWERING3 (ELF3) controls the link between root constraint and altered shoot growth. This provides an entry point to study how root and shoot growth are integrated to respond to environmental stimuli.
authors.affiliation: Department of Plant Sciences, University of California, Davis, California 95616 Bayer Crop Science, Crop Genetics Department, Morrisville, North Carolina 27560.
authors.forename: Bindu
authors.identifier: http://orcid.org/0000-0001-9298-629X
authors.initials: B
authors.lastname: Joseph
authors.affiliation: Department of Plant Sciences, University of California, Davis, California 95616.
authors.forename: Lillian
authors.initials: L
authors.lastname: Lau
authors.affiliation: Department of Plant Sciences, University of California, Davis, California 95616 DynaMo Center of Excellence, University of Copenhagen, DK-1871 Frederiksberg C, Denmark kliebenstein@ucdavis.edu.
authors.forename: Daniel J
authors.identifier: http://orcid.org/0000-0001-5759-3175
authors.initials: DJ
authors.lastname: Kliebenstein
mesh_terms: D000465:Algorithms; D017360:Arabidopsis / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics*; D004843:Epistasis, Genetic; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D005838:Genotype; D008957:Models, Genetic; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D018517:Plant Roots / Q000235:genetics* / Q000254:growth & development; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development; D040641:Quantitative Trait Loci / Q000235:genetics*; D058441:Rhizosphere; D013045:Species Specificity; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D014157:Transcription Factors; C432430:At2g25930 protein, Arabidopsis