title: Absence of fluence rate dependency of phytochrome modulation of stem extension in light-grown Sinapis alba L.
abstract: In background white light, supplementary far-red (λmax 700 nm) is an order of magnitude less effective than supplementary far-red (λmax 739 nm) in the stimulation of stem extension in Sinapis alba. The relationship between phytochrome photoequilibrium and extension rate increase for the two supplementary far-red treatments is, however, very similar. This evidence indicates that phytochrome cycling is not involved in the phytochrome control of stem extension in light-grown Sinapis alba and that the response to supplementary far-red light is not fluence rate (irradiance) dependent.
authors.affiliation: Department of Botany, Adrian Building, University of Leicester, University Road, LE1 7RH, Leicester, U.K..
authors.forename: D C
authors.initials: DC
authors.lastname: Morgan
authors.forename: R
authors.initials: R
authors.lastname: Child
authors.forename: H
authors.initials: H
authors.lastname: Smith