title: Photoreceptor-mediated kin recognition in plants.
abstract: Although cooperative interactions among kin have been established in a variety of biological systems, their occurrence in plants remains controversial. Plants of Arabidopsis thaliana were grown in rows of either a single or multiple accessions. Plants recognized kin neighbours and horizontally reoriented leaf growth, a response not observed when plants were grown with nonkin. Plant kin recognition involved the perception of the vertical red/far-red light and blue light profiles. Disruption of the light profiles, mutations at the PHYTOCHROME B, CRYPTOCHROME 1 or 2, or PHOTOTROPIN 1 or 2 photoreceptor genes or mutations at the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS1 gene required for auxin (growth hormone) synthesis impaired the response. The leaf-position response increases plant self-shading, decreases mutual shading between neighbours and increases fitness. Light signals from neighbours are known to shape a more competitive plant body. Here we show that photosensory receptors mediate cooperative rather than competitive interactions among kin neighbours by reducing the competition for local pools of resources.
authors.affiliation: IFEVA, Facultad de Agronomía, Universidad de Buenos Aires and CONICET, Av. San Martín 4453, 1417, Buenos Aires, Argentina.
authors.forename: María A
authors.initials: MA
authors.lastname: Crepy
authors.forename: Jorge J
authors.initials: JJ
authors.lastname: Casal
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D055537:Light Signal Transduction; D055519:Photoreceptors, Plant / Q000378:metabolism*; D018515:Plant Leaves / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D055519:Photoreceptors, Plant
keywords: competition; cryptochrome; fitness; kin; phototropin; phytochrome; shade avoidance