title: Genetic engineering of harvest index in tobacco through overexpression of a phytochrome gene.
abstract: The phytochrome photoreceptor family regulates plant architecture in response to environmental light signals. Phytochromes mediate the shade avoidance syndrome, in which plants react to far-red radiation reflected from neighbors by elongation growth, occurring at the expense of leaf and storage organ production. We show that transgenic overproduction of phytochrome A in tobacco suppresses shade avoidance, causing proximity-conditional dwarfing. At high densities in the field, assimilates show an enhanced allocation to leaves, with a concomitant increase in harvest index. Transfer of this approach to other crop plants could provide significant improvements in productivity.
authors.affiliation: Department of Botany, University of Leicester, UK.
authors.forename: P R
authors.initials: PR
authors.lastname: Robson
authors.forename: A C
authors.initials: AC
authors.lastname: McCormac
authors.forename: A S
authors.initials: AS
authors.lastname: Irvine
authors.forename: H
authors.initials: H
authors.lastname: Smith
mesh_terms: D001709:Biotechnology; D004463:Ecology; D010641:Phenotype; D010834:Phytochrome / Q000235:genetics*; D051942:Phytochrome A; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D015202:Protein Engineering; D014026:Nicotiana / Q000235:genetics*
chemical_list: D051942:Phytochrome A; D010834:Phytochrome