Metabolic Profile and Performance Responses of Ranunculus asiaticus L. Hybrids as Affected by Light Quality of Photoperiodic Lighting

Ranunculus asiaticus is a quantitative long day plant grown for cut flowers and flowering potted plants production. We evaluated the influence of light spectrum of three light sources for end-of-day photoperiodic treatments, with different phytochrome photoequilibria (PPE) induced at plant level, on the metabolic profiling of two hybrids of R. asiaticus L., MBO and MDR, in plants from vernalized tuberous roots. The following treatments were compared with natural day length (NL): white fluorescence lamp (FL, PPE 0.84), light emitting diodes (LEDs) Red:Far Red light at 3:1 ratio (R:FR 3:1, PPE 0.84), and LEDs Red:Far Red light at 1:3 ratio (R:FR 1:3, PPE 0.63). Measurements were carried out to evaluate the time course of carbohydrate, amino acid, and protein levels throughout the growing cycle in tuberous roots and leaves, in relation to the different plant stages (pre-planting, vegetative phase, and flowering). The study of metabolic profiling suggested that the differences between the tuberous root reserves of the two R. asiaticus hybrids could be responsible for the capacity of MBO to exert an early flowering. In particular, the proton-consuming synthesis during the pre-planting of two amino acids, alanine and γ-aminobutyric acid (GABA), is able to buffer the cytoplasmic acidosis and pH altered by the vernalization process, and GABA itself can efficiently scavenge reactive oxygen species. This fast response to the stress caused by vernalization allows MBO plants to accelerate the process of vegetative development and flowering. Some other changes in metabolites profile were certainly related to the different responses to day length and photoperiodic light quality in the two hybrids, such as dose exerted by low R:FR lighting in both MBO and MDR. However, most of the responses are under a strict genetic control.

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The role of light quality of photoperiodic lighting on photosynthesis, flowering and metabolic profiling in Ranunculus asiaticus L.

Physiologia Plantarum ◽

10.1111/ppl.13122 ◽

2020 ◽

Vol 170 (2) ◽

pp. 187-201

Author(s):

Giuseppe C. Modarelli ◽

Carmen Arena ◽

Giuseppe Pesce ◽

Emilia Dell'Aversana ◽

Giovanna M. Fusco ◽

...

Keyword(s):

Metabolic Profiling ◽

Light Quality ◽

Ranunculus Asiaticus ◽

Role Of Light

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634 Effects of Light Sources for Light Period Extension on Growth and Fowering in Statice

HortScience ◽

10.21273/hortsci.35.3.507a ◽

2000 ◽

Vol 35 (3) ◽

pp. 507A-507

Author(s):

Dong-Lim Yoo ◽

Seung-Woo Lee

Keyword(s):

Red Light ◽

High Ratio ◽

Light Period ◽

Day Length ◽

Artificial Light ◽

Light Sources ◽

Chlorophyll Contents ◽

Fluorescent Lamps ◽

Light Absorbance ◽

Incandescent Lamps

This experiment was conducted to investigate the effects of artificial light sources for light period extension on growth and flowering of statice `Sophia' and `Early Blue'. The seeds were sown on 10 June in a plug tray with 128 plugs. The seedlings were grown at the highland (800 m above sea level) for 50 days, and transplanted on 30 July in 20-cm-diameter plastic pots. High-pressure sodium lamps (HPS) (220V, 400W), incandescent lamps (Il) (220V, 200W), and fluorescent lamps (Fl) (220V, 40W) for day length extension (16-h photoperiod) as compared with short day (8-h photoperiod) were tested. HPS gave the greatest photosynthetically active radiation (PAR), but Fl did the smallest. HPS or Fl as compared with Il showed high ratio of red/far-red light. The leaves of plant grown under HPS were effective for light absorbance and chlorophyll contents. HPS promoted photosynthesis as much as light period extension, while more respiration than photosynthesis occurred under Fl affected by low PAR. Long day condition as light period extension hastened flowering of statice, and HPS or Il were more effective than Fl on flowering among artificial light sources tested. The light compensation and saturation points of statice were 50 and 500 μmol·m–2·s–1, respectively. Photosynthesis hastened at high temperature, but amount of photosynthesis at vegetative stage showed much higher than flowering stage under the condition below 20 °C These results indicated that day length extension with HPS increased productivity and quality for cut flower of statice at the highland in Korea.

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The Effect of Light Spectrum on the Morphology and Cannabinoid Content of Cannabis sativa L.

Medical Cannabis and Cannabinoids ◽

10.1159/000489030 ◽

2018 ◽

Vol 1 (1) ◽

pp. 19-27 ◽

Cited By ~ 12

Author(s):

Gianmaria Magagnini ◽

Gianpaolo Grassi ◽

Stiina Kotiranta

Keyword(s):

Light Intensity ◽

Cannabis Sativa ◽

Red Light ◽

Total Yield ◽

Plant Morphology ◽

Dry Weight ◽

Light Sources ◽

Light Spectrum ◽

Light Spectra ◽

Generative Phase

Cannabis sativa L. flowers are the main source of Δ-9-tetrahydrocannabinol (THC) used in medicine. One of the most important growth factors in cannabis cultivation is light; light quality, light intensity, and photoperiod play a big role in a successful growth protocol. The aim of the present study was to examine the effect of 3 different light sources on morphology and cannabinoid production. Cannabis clones were grown under 3 different light spectra, namely high-pressure sodium (HPS), AP673L (LED), and NS1 (LED). Light intensity was set to ∼450 µmol/m2/s measured from the canopy top. The photoperiod was 18L: 6D/21 days during the vegetative phase and 12L: 12D/46 days during the generative phase, respectively. At the end of the experiment, plant dry weight partition, plant height, and cannabinoid content (THC, cannabidiol [CBD], tetrahydrocannabivarin [THCV], cannabigerol [CBG]) were measured under different light treatments. The experiment was repeated twice. The 3 light treatments (HPS, NS1, AP673L) resulted in differences in cannabis plant morphology and in cannabinoid content, but not in total yield of cannabinoids. Plants under HPS treatment were taller and had more flower dry weight than those under treatments AP673L and NS1. Treatment NS1 had the highest CBG content. Treatments NS1 and AP673L had higher CBD and THC concentrations than the HPS treatment. Results were similar between experiments 1 and 2. Our results show that the plant morphology can be manipulated with the light spectrum. Furthermore, it is possible to affect the accumulation of different cannabinoids to increase the potential of medicinal grade cannabis. In conclusion, an optimized light spectrum improves the value and quality of cannabis. Current LED technology showed significant differences in growth habit and cannabinoid profile compared to the traditional HPS light source. Finally, no difference of flowering time was observed under different R:FR (i.e., the ratio between red and far-red light).

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Light Spectrum Differentially Affects the Yield and Phytochemical Content of Microgreen Vegetables in a Plant Factory

Plants ◽

10.3390/plants10102182 ◽

2021 ◽

Vol 10 (10) ◽

pp. 2182

Author(s):

Filippos Bantis

Keyword(s):

Red Light ◽

Farming System ◽

Soluble Solids ◽

Carotenoid Content ◽

Total Phenolic ◽

Light Sources ◽

Light Spectrum ◽

Hypocotyl Length ◽

Phytochemical Content ◽

Spectral Bands

Light quality exerts considerable effects on crop development and phytochemical content. Moreover, crops grown as microgreens are ideal for plant factories with artificial lighting, since they contain greater amounts of bioactive compounds compared to fully-grown plants. The aim of the present study was to evaluate the effect of broad-spectra light with different red/blue ratios on the yield, morphology, and phytochemical content of seven microgreens. Mustard, radish, green basil, red amaranth, garlic chives, borage, and pea shoots were grown in a vertical farming system under three light sources emitting red/blue ratios of about 2, 5, and 9 units (RB2, RB5, and RB9, respectively). Mustard exhibited the most profound color responses. The yield was enhanced in three microgreens under RB9 and in garlic under RB2. Both the hypocotyl length and the leaf and cotyledon area were significantly enhanced by increasing the red light in three microgreens each. Total soluble solids (Brix) were reduced in 4 microgreens under RB2. The total phenolic content and antioxidant capacity were reduced under RB2 in 6 and 5 microgreens, respectively. The chlorophylls were variably affected but total the carotenoid content was reduced in RB9 in three microgreens. Overall, light wavelength differentially affected the microgreens’ quality, while small interplays in spectral bands enhanced their phytochemical content.

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EFFECTS OF SPECTRAL FILTERS ON GROWTH OF ROSA × HYBRIDA AND EXACUM AFFINE.

HortScience ◽

10.21273/hortsci.25.8.849a ◽

1990 ◽

Vol 25 (8) ◽

pp. 849a-849

Author(s):

Margaret J McMahon ◽

John W. Kelly

Keyword(s):

Light Quality ◽

Red Light ◽

Photosynthetic Photon Flux Density ◽

Photon Flux ◽

Photon Flux Density ◽

Textile Dye ◽

Light Spectrum ◽

Spectral Filters ◽

Leaf Chlorophyll ◽

Exacum Affine

The growth of Rosa × hybrida and Exacum affine under different spectral filters was evaluated. Three filters that altered light quality were developed. One, a red textile dye, filtered out much of the blue/green portion of the light spectrum but did not change far-red to red (FR/R) light ratio. Another, a blue textile dye, raised FR/R by filtering out a portion of red light. The third, a salt (copper sulfate) lowered FR/R by filtering out a greater portion of far-red than red light. Two controls were used that did not alter light quality. The filters were installed in specally built growth chambers. Photosynthetic Photon Flux Density (PPFD) was adjusted to equal values in each chamber. Plants of both species were significantly shorter and had higher leaf chlorophyll, when grown under the low FR/R filter.

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Postnatal growth rate and gonadal development in circadian tau mutant hamsters reared in constant dim red light

Reproduction ◽

10.1530/reprod/118.2.327 ◽

2000 ◽

pp. 327-330 ◽

Cited By ~ 7

Author(s):

RJ Lucas ◽

JA Stirland ◽

YN Mohammad ◽

AS Loudon

Keyword(s):

Time Course ◽

Red Light ◽

Somatic Growth ◽

Postnatal Growth ◽

Gonadal Development ◽

Testicular Development ◽

Wild Type ◽

Similar Time ◽

Syrian Hamsters ◽

Body Weights

The role of the circadian clock in the reproductive development of Syrian hamsters (Mesocricetus auratus was examined in wild type and circadian tau mutant hamsters reared from birth to 26 weeks of age under constant dim red light. Testis diameter and body weights were determined at weekly intervals in male hamsters from 4 weeks of age. In both genotypes, testicular development, subsequent regression and recrudescence exhibited a similar time course. The age at which animals displayed reproductive photosensitivity, as exhibited by testicular regression, was unrelated to circadian genotype (mean +/- SEM: 54 +/- 3 days for wild type and 59 +/- 5 days for tau mutants). In contrast, our studies revealed a significant impact of the mutation on somatic growth, such that tau mutants weighed 18% less than wild types at the end of the experiment. Our study reveals that the juvenile onset of reproductive photoperiodism in Syrian hamsters is not timed by the circadian system.

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The Preferences of Different Cultivars of Lettuce Seedlings (Lactuca sativa L.) for the Spectral Composition of Light

Agronomy ◽

10.3390/agronomy11061211 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1211

Author(s):

Barbara Frąszczak ◽

Monika Kula-Maximenko

Keyword(s):

Chlorophyll Content ◽

Blue Light ◽

White Light ◽

Leaf Shape ◽

Red Light ◽

Spectral Composition ◽

Fresh Weight ◽

Light Spectrum ◽

Dark Green ◽

Relative Chlorophyll Content

The spectrum of light significantly influences the growth of plants cultivated in closed systems. Five lettuce cultivars with different leaf colours were grown under white light (W, 170 μmol m−2 s−1) and under white light with the addition of red (W + R) or blue light (W + B) (230 μmol m−2 s−1). The plants were grown until they reached the seedling phase (30 days). Each cultivar reacted differently to the light spectrum applied. The red-leaved cultivar exhibited the strongest plasticity in response to the spectrum. The blue light stimulated the growth of the leaf surface in all the plants. The red light negatively influenced the length of leaves in the cultivars, but it positively affected their number in red and dark-green lettuce. It also increased the relative chlorophyll content and fresh weight gain in the cultivars containing anthocyanins. When the cultivars were grown under white light, they had longer leaves and higher value of the leaf shape index. The light-green cultivars had a greater fresh weight. Both the addition of blue and red light significantly increased the relative chlorophyll content in the dark-green cultivar. The spectrum enhanced with blue light had positive influence on most of the parameters under analysis in butter lettuce cultivars. These cultivars were also characterised by the highest absorbance of blue light.

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Photocatalytic Activity and Characterization of Carbon-Modified Titania for Visible-Light-Active Photodegradation of Nitrogen Oxides

International Journal of Photoenergy ◽

10.1155/2012/548647 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13 ◽

Cited By ~ 6

Author(s):

Chun-Hung Huang ◽

Yu-Ming Lin ◽

I-Kai Wang ◽

Chun-Mei Lu

Keyword(s):

Visible Light ◽

Carbon Number ◽

Red Light ◽

Matrix Material ◽

Carbon Sources ◽

Impregnation Method ◽

Light Spectrum ◽

Precursor Molecule ◽

Visible Light Active ◽

Carbonate Species

A variety of carbon-modified titania powders were prepared by impregnation method using a commercial available titania powder, Hombikat UV100, as matrix material while a range of alcohols from propanol to hexanol were used as precursors of carbon sources. Rising the carbon number of alcoholic precursor molecule, the modified titania showed increasing visible activities ofNOxphotodegradation. The catalyst modified with cyclohexanol exhibited the best activities of 62%, 62%, 59%, and 54% for the totalNOxremoval under UV, blue, green, and red light irradiation, respectively. The high activity with long wavelength irradiation suggested a good capability of photocatalysis in full visible light spectrum. Analysis of UV-visible spectrum indicated that carbon modification promoted visible light absorption and red shift in band gap. XPS spectroscopic analysis identified the existence of carbonate species (C=O), which increased with the increasing carbon number of precursor molecule. Photoluminescence spectra demonstrated that the carbonate species suppressed the recombination rate of electron-hole pair. As a result, a mechanism of visible-light-active photocatalyst was proposed according to the formation of carbonate species on carbon-modified TiO2.

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