Genetic engineering of harvest index in tobacco through overexpression of a phytochrome gene.
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.
Robson
P R
PR
Department of Botany, University of Leicester, UK.
McCormac
A C
AC
Irvine
A S
AS
Smith
H
H
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*
D051942:Phytochrome A; D010834:Phytochrome