title: Optimizing LED lighting for space plant growth unit: Joint effects of photon flux density, red to white ratios and intermittent light pulses.
abstract: The aim of this work were to choose a quantitative optimality criterion for estimating the quality of plant LED lighting regimes inside space greenhouses and to construct regression models of crop productivity and the optimality criterion depending on the level of photosynthetic photon flux density (PPFD), the proportion of the red component in the light spectrum and the duration of the duty cycle (Chinese cabbage Brassica сhinensis L. as an example). The properties of the obtained models were described in the context of predicting crop dry weight and the optimality criterion behavior when varying plant lighting parameters. Results of the fractional 3-factor experiment demonstrated the share of the PPFD level participation in the crop dry weight accumulation was 84.4% at almost any combination of other lighting parameters, but when PPFD value increased up to 500µmol m-2s-1the pulse light and supplemental light from red LEDs could additionally increase crop productivity. Analysis of the optimality criterion response to variation of lighting parameters showed that the maximum coordinates were the following: PPFD = 500µmol m-2s-1, about 70%-proportion of the red component of the light spectrum (PPFDLEDred/PPFDLEDwhite= 1.5) and the duty cycle with a period of 501µs. Thus, LED crop lighting with these parameters was optimal for achieving high crop productivity and for efficient use of energy in the given range of lighting parameter values.
authors.affiliation: Lomonosov Moscow State University, Moscow, Russia.
authors.forename: O V
authors.initials: OV
authors.lastname: Avercheva
authors.affiliation: State Science Center - Institute for Biomedical Problems RAS, Moscow, Russia.
authors.forename: Yu A
authors.initials: YA
authors.lastname: Berkovich
authors.affiliation: State Science Center - Institute for Biomedical Problems RAS, Moscow, Russia.
authors.forename: I O
authors.initials: IO
authors.lastname: Konovalova
authors.affiliation: National Technical University of Ukraine "Kyiv polytechnical institute", Kyiv, Ukraine.
authors.forename: S G
authors.initials: SG
authors.lastname: Radchenko
authors.affiliation: National Technical University of Ukraine "Kyiv polytechnical institute", Kyiv, Ukraine.
authors.forename: S N
authors.initials: SN
authors.lastname: Lapach
authors.affiliation: Lomonosov Moscow State University, Moscow, Russia.
authors.forename: E M
authors.initials: EM
authors.lastname: Bassarskaya
authors.affiliation: Lomonosov Moscow State University, Moscow, Russia. Electronic address: galina.kochetova@gmail.com.
authors.forename: G V
authors.initials: GV
authors.lastname: Kochetova
authors.affiliation: Lomonosov Moscow State University, Moscow, Russia.
authors.forename: T V
authors.initials: TV
authors.lastname: Zhigalova
authors.affiliation: Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Moscow, Russia.
authors.forename: O S
authors.initials: OS
authors.lastname: Yakovleva
authors.affiliation: Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Moscow, Russia.
authors.forename: I G
authors.initials: IG
authors.lastname: Tarakanov
mesh_terms: D001937:Brassica / Q000254:growth & development* / Q000528:radiation effects*; D000069599:Crop Production / Q000379:methods*; D005118:Extraterrestrial Environment; D008027:Light; D008029:Lighting / Q000379:methods*; D017785:Photons; D010788:Photosynthesis / Q000528:radiation effects; D063245:Plant Development / Q000528:radiation effects*; D018515:Plant Leaves / Q000254:growth & development / Q000528:radiation effects; D013026:Space Flight; D018531:Spacecraft
keywords: A fractional multiple-factor experiment; Light spectrum; Optimality criterion; Pulsed light; Regression analysis; Space greenhouse