Far‐red photons have equivalent efficiency to traditional photosynthetic photons: Implications for redefining photosynthetically active radiation

Zhen, Shuyang; Bugbee, Bruce

doi:10.1111/pce.13730

Cited by 175 publications

(204 citation statements)

References 66 publications

Supporting

Mentioning

184

Contrasting

Order By: Relevance

“…Despite the classic definition of PAR, recent studies indicate that far-red photons (700-750 nm) are photosynthetically synergistic with shorter wavelength photons 51,52 . These photons are thus being reconsidered for their role in photosynthesis.…”

Section: Spectral Effects On Plant Shape and Photosynthesismentioning

confidence: 99%

From physics to fixtures to food: current and potential LED efficacy

Pattison²,

2020

Self Cite

View full text Add to dashboard Cite

In this paper, LED refers to an LED package, which is the LED chip inside a housing. The housing/packaging enables mechanical and electrical connections to the fixture, provides a thermal path, affects photon distribution, and includes the phosphor layer for white LEDs (see below). LED performance specifications are for LED packages. An LED fixture refers to LED packages integrated into a fixture.]

show abstract

Section: Spectral Effects On Plant Shape and Photosynthesismentioning

confidence: 99%

From physics to fixtures to food: current and potential LED efficacy

Pattison²,

2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Whole-plant gas exchange measurements of 16 C 3 and two C 4 species under red/blue light and red/blue plus FR light indicated that adding far-red photons (10 -30 % of PPFD) caused similar increases in the whole canopy photosynthetic rate as adding the same amount of red/ blue photons (Zhen & Bugbee, 2019). To demonstrate that far-red photons are equally efficient at driving photosynthesis, the authors grew lettuce under spectra with or without 15 % of far-red photons at the same total photon flux, and the results at harvest showed 35 % higher dry biomass in treatments with far-red photons, which was almost entirely caused by enhanced radiation capture through leaf expansion.…”

Section: Photosynthesis and Biomass Produc-tionmentioning

confidence: 93%

The role of far-red light (FR) in photomorphogenesis and its use in greenhouse plant production

Kump

2020

AAS

View full text Add to dashboard Cite

<p>Light energy is one of the most important factors regulating the growth and development of plants. In greenhouses and other controlled- environments in which the natural radiation intensities are often low, plant production relies on supplementary lighting to optimize the photosynthesis, increase production levels, and enable year-round production. For a long time, the research related to artificial lighting sources focused on the optimization of the efficiency of use for photosynthesis. The quality of light in plant production has been widely addressed only recently with the development of advanced LED technology that is energy efficient and enables the control of the spectral composition of light. Red and far-red light are sensed by the phytochromes that trigger several morphological and developmental processes that impact productivity and yield quality. Thus, to efficiently exploit all the advantages of LEDs and to develop LED arrays for specific plant applications, it is essential to understand thoroughly how light quality influences plant growth and development. This paper presents an overview of the recent developments in light quality manipulation, focusing on far-red light and the R: FR ratio, to improve yield and quality of products and to manage plant architecture and flowering in vegetable and ornamental horticulture.</p>

show abstract

“…Recently, Zhen and van Iersel (2017) found a synergistic interaction between far-red light and PAR, specifically an increase in net photosynthesis of lettuce (Lactuca sativa) in response to added far-red light. Zhen and Bugbee (2020) found that adding far-red light (up to 40% of PAR) increased canopy photosynthesis of 14 diverse agronomic and horticultural crop species as much as adding the same photon flux of PAR.…”

mentioning

confidence: 97%

“…This has the potential to shorten cropping cycles of ornamental plants grown in controlled environments. One approach to enhancing growth is to include far-red light (l = 700-800 nm) in the spectrum because 1) farred light can trigger a shade-avoidance and/or acclimation response (Franklin, 2008;Keuskamp et al, 2010;Possart et al, 2014) and 2) it is photosynthetically active (Zhen and Bugbee, 2020;Zhen and van Iersel, 2017).…”

mentioning

confidence: 99%

“…Excessive elongation is undesirable in seedling production and a potential drawback to providing high levels of far-red light. Compared with the PPFD, sunlight has about 19% far-red photons [701-750 nm (Zhen and Bugbee, 2020)], so plants are accustomed to receiving a substantial amount of far-red light. For decades, far-red light has been considered outside of the range of photosynthetically active radiation [PAR (400-700 nm)], as established by Hoover (1937), McCree (1971), and Inada (1976), even though they demonstrated that far-red light had at least some photosynthetic activity.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Supplemental Far-red Light-emitting Diode Light Increases Growth of Foxglove Seedlings Under Sole-source Lighting

Elkins¹,

Iersel²

2020

hortte

View full text Add to dashboard Cite

Seedlings may be grown indoors where environmental conditions can be precisely controlled to ensure consistent and reliable production. The optimal spectrum for production under sole-source lighting is currently unknown. Far-red light (λ = 700–800 nm) typically is not a significant part of the spectrum of light-emitting diode (LED) grow lights. However, far-red light is photosynthetically active and can enhance leaf elongation, which may result in larger leaves and increased light interception. We hypothesized that adding far-red light to sole-source lighting would increase the growth of ‘Dalmatian Peach’ foxglove (Digitalis purpurea) seedlings grown under white LED lights, potentially shortening production times. Our objective was to evaluate the effect of far-red light intensities, ranging from 4.0 to 68.8 µmol·m−2·s−1, on the growth and morphology of foxglove seedlings. Foxglove seedlings were grown in a growth chamber with a photosynthetic photon flux density (PPFD) of 186 ± 6.4 μmol·m−2·s−1 and supplemental far-red light intensities ranging from 4.0 to 68.8 µmol·m−2·s−1. As far-red light increased, shoot dry weight, root dry weight, plant height, and plant height/number of leaves increased by 38% (P = 0.004), 20% (P = 0.029), 38% (P = 0.025), and 34% (P = 0.024), respectively, while root weight fraction decreased 16% (P = 0.034). Although we expected supplemental far-red light to induce leaf and/or stem expansion, specific leaf area and compactness (two measures of morphology) were unaffected. Because a 37% increase in total photon flux density (PPFD plus far-red light) resulted in a 34.5% increase in total plant dry weight, the increased growth likely was due to increased photosynthesis rather than a shade-acclimation response. The growth response was linear across the 4.0 to 68.8 µmol·m−2·s−1 range of far-fed light tested, so we were unable to determine a saturating far-red photon flux density.

show abstract

Far‐red photons have equivalent efficiency to traditional photosynthetic photons: Implications for redefining photosynthetically active radiation

Cited by 175 publications

References 66 publications

From physics to fixtures to food: current and potential LED efficacy

From physics to fixtures to food: current and potential LED efficacy

The role of far-red light (FR) in photomorphogenesis and its use in greenhouse plant production

Supplemental Far-red Light-emitting Diode Light Increases Growth of Foxglove Seedlings Under Sole-source Lighting

Contact Info

Product

Resources

About