EFFECT OF WHITE, RED, AND BLUE LIGHT ON THE NATURE OF THE PRODUCTS OF PHOTOSYNTHESIS IN TOBACCO LEAVES

1962 ◽  
Vol 40 (2) ◽  
pp. 317-326 ◽  
Author(s):  
E. B. Tregunna ◽  
G. Krotkov ◽  
C. D. Nelson
Keyword(s):  
Carbon Dioxide ◽  
Blue Light ◽  
Soluble Fraction ◽  
Incident Light ◽  
Soluble Sugars ◽  
Red Light ◽  
Considerable Decrease ◽  
Tobacco Leaves ◽  
Tentative Explanation ◽  
Photosynthetic Products

Detached tobacco leaves were placed singly into a photosynthesis chamber and illuminated in the presence of C14O2 with white, red, or blue light. Two kinds of experiments were carried out. In the first, the energy of the three kinds of incident light was adjusted so that the rate of CO2 uptake was the same. In the second, the energy of the three kinds of incident light was the same and the time adjusted so that an equal amount of CO2 was taken up by each leaf. At the end of photosynthesis the distribution of C14 was determined in the ethanol-soluble and-insoluble fractions and among the various compounds of the ethanol-soluble fraction that were separated by paper chromatography.No effect of wavelength of light was observed on the distribution of absorbed carbon dioxide between the ethanol-soluble and -insoluble fractions. Neither was there any evidence that red light stimulated synthesis of soluble sugars. Red light, compared with white, increased incorporation of carbon dioxide into glycine, but had no effect on serine. Blue brought about a considerable decrease in glycine and some decrease in serine.A tentative explanation is given of a mechanism by means of which the wavelength of light may affect the distribution of absorbed carbon dioxide among the various photosynthetic products.

scholarly journals Transcriptomic and Metabolomic Profiling Reveals the Effect of LED Light Quality on Fruit Ripening and Anthocyanin Accumulation in Cabernet Sauvignon Grape

2021 ◽  
Vol 8 ◽  
Author(s):  
Peian Zhang ◽  
Suwen Lu ◽  
Zhongjie Liu ◽  
Ting Zheng ◽  
Tianyu Dong ◽  
...  
Keyword(s):  
Blue Light ◽  
White Light ◽  
Plant Traits ◽  
Soluble Sugars ◽  
Red Light ◽  
Green Light ◽  
Grape Berries ◽  
Light Spectra ◽  
Metabolomic Profiling ◽  
Highly Expressed Genes

Different light qualities have various impacts on the formation of fruit quality. The present study explored the influence of different visible light spectra (red, green, blue, and white) on the formation of quality traits and their metabolic pathways in grape berries. We found that blue light and red light had different effects on the berries. Compared with white light, blue light significantly increased the anthocyanins (malvidin-3-O-glucoside and peonidin-3-O-glucoside), volatile substances (alcohols and phenols), and soluble sugars (glucose and fructose), reduced the organic acids (citric acid and malic acid), whereas red light achieved the opposite effect. Transcriptomics and metabolomics analyses revealed that 2707, 2547, 2145, and 2583 differentially expressed genes (DEGs) and (221, 19), (254, 22), (189, 17), and (234, 80) significantly changed metabolites (SCMs) were filtered in the dark vs. blue light, green light, red light, and white light, respectively. According to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, most of the DEGs identified were involved in photosynthesis and biosynthesis of flavonoids and flavonols. Using weighted gene co-expression network analysis (WGCNA) of 23410 highly expressed genes, two modules significantly related to anthocyanins and soluble sugars were screened out. The anthocyanins accumulation is significantly associated with increased expression of transcription factors (VvHY5, VvMYB90, VvMYB86) and anthocyanin structural genes (VvC4H, Vv4CL, VvCHS3, VvCHI1, VvCHI2, VvDFR), while significantly negatively correlated with VvPIF4. VvISA1, VvISA2, VvAMY1, VvCWINV, VvβGLU12, and VvFK12 were all related to starch and sucrose metabolism. These findings help elucidate the characteristics of different light qualities on the formation of plant traits and can inform the use of supplemental light in the field and after harvest to improve the overall quality of fruit.

scholarly journals The Physiological Response of Lettuce to Red and Blue Light Dynamics Over Different Photoperiods

2021 ◽  
Vol 11 ◽  
Author(s):  
Giedrė Samuolienė ◽  
Akvilė Viršilė ◽  
Jurga Miliauskienė ◽  
Perttu J. Haimi ◽  
Kristina Laužikė ◽  
...  
Keyword(s):  
Blue Light ◽  
Physiological Response ◽  
Nutritive Value ◽  
Leaf Gas Exchange ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Red Light ◽  
Antioxidant Properties ◽  
Photon Flux ◽  
Light Spectrum

This study aimed to evaluate the effect of dynamic red and blue light parameters on the physiological responses and key metabolites in lettuce and also the subsequent impact of varying light spectra on nutritive value. We explored the metabolic changes in carotenes, xanthophylls, soluble sugars, organic acids, and antioxidants; the response of photosynthetic indices [photosynthetic (Pr) and transpiration (Tr) rates]; and the intracellular to ambient CO2 concentration ratios (Ci/Ca) in lettuce (Lactuca sativa L. “Lobjoits Green Cos”). They were cultivated under constant (con) or parabolic (dyn) blue (B, 452 nm) and/or red (R, 662 nm) light-emitting diode (LED) photosynthetic photon flux densities (PPFDs) at 12, 16, and 20 h photoperiods, maintaining consistent daily light integrals (DLIs) for each light component in all treatments, at 2.3 and 9.2 mol m–2 per day for blue and red light, respectively. The obtained results and principal component analysis (PCA) confirmed a significant impact of the light spectrum, photoperiod, and parabolic profiles of PPFD on the physiological response of lettuce. The 16 h photoperiod resulted in significantly higher content of xanthophylls (neoxanthin, violaxanthin, lutein, and zeaxanthin) in lettuce leaves under both constant and parabolic blue light treatments (BconRdyn 16 h and BdynRdyn 16 h, respectively). Lower PPFD levels under a 20 h photoperiod (BdynRdyn 20 h) as well as higher PPFD levels under a 12 h photoperiod (BdynRdyn 12 h) had a pronounced impact on leaf gas exchange indices (Pr, Tr, Ci/Ca), xanthophylls, soluble sugar contents, and antioxidant properties of lettuce leaves. The parabolic PPFD lighting profile over a 16 h photoperiod (BdynRdyn 16 h) led to a significant decrease in Ci/Ca, which resulted in decreased Pr and Tr, compared with constant blue or red light treatments with the same photoperiod (BconRdyn and BdynRcon 16 h). Additionally, constant blue lighting produced higher α + β-carotene and anthocyanin (ARI) content and increased carotenoid to chlorophyll ratio (CRI) but decreased biomass accumulation and antioxidant activity.

scholarly journals Light-emitting diode spectra modify nutritional status, physiological response, and secondary metabolites in Ficus hirta and Alpinia oxyphylla

2021 ◽  
Vol 49 (2) ◽  
pp. 12314
Author(s):  
Changwei ZHOU ◽  
Chongfei SHANG ◽  
Feiyu CHEN ◽  
Junzhou BAO ◽  
Lifei YU ◽  
...  
Keyword(s):  
Blue Light ◽  
Light Emitting Diode ◽  
Soluble Sugars ◽  
Red Light ◽  
Green Light ◽  
Light Spectrum ◽  
Wide Bandwidth ◽  
Alpinia Oxyphylla ◽  
Fine Root Length ◽  
Ficus Hirta

Lighting spectrum is one of the key factors that determine biomass production and secondary-metabolism accumulation in medicinal plants under artificial cultivation conditions. Ficus hirta and Alpinia oxyphylla seedlings were cultured with blue (10% red, 10% green, 70% blue), green (20% red, 10% green, 30% blue), and red-enriched (30% red, 10% green, 20% blue) lights in a wide bandwidth of 400-700 nm. F. hirta seedlings had lower diameter, fine root length, leaf area, biomass, shoot nutrient (N) and phosphorus concentrations in the blue-light spectrum compared to the red- and green-light spectra. In contrast, A. oxyphylla seedlings showed significantly higher concentrations of foliar flavonoids and saponins in red-light spectrum with rare responses in N, chlorophyll, soluble sugars, and starch concentrations. F. hirta is easily and negatively impacted by blue-light spectrum but A. oxyphylla is suitably used to produce flavonoid and saponins in red-light spectrum across a wide bandwidth.

scholarly journals Blue/green light-responsive cyanobacteriochromes are cell shade sensors in red-light replete niches

2019 ◽  
Author(s):  
Gen Enomoto ◽  
Masahiko Ikeuchi
Keyword(s):  
Cell Density ◽  
Blue Light ◽  
Hot Springs ◽  
Incident Light ◽  
Natural Habitat ◽  
Red Light ◽  
Green Light ◽  
Light Response ◽  
Cell Aggregation ◽  
Cell Position

SummaryPhotoautotrophic cyanobacteria have developed sophisticated light response systems to capture and utilize the energy and information of incident light [1]. Cyanobacteria-specific photoreceptors cyanobacteriochromes (CBCRs) are distantly related to more widespread phytochromes. CBCRs show the most diverse spectral properties among the naturally occurring photoreceptors, typified by a unique and prevailing blue/green light-absorbing variant [2–6]. However, where the CBCR-mediated ‘colorful’ signaling systems function in nature has been elusive. We previously reported that the three CBCRs SesA/B/C synthesize/degrade a bacterial second messenger cyclic diguanylate (c-di-GMP) in response to blue/green light [6–8]. The cooperative action of SesA/B/C enables blue light-ON and green light-OFF regulation of the c-di-GMP-dependent cell aggregation of the thermophilic cyanobacterium Thermosynechococcus vulcanus [8, 9]. Here, we report that SesA/B/C can serve as a physiological sensor of cell density. Because cyanobacterial cells show lower transmittance of blue light than green light, higher cell density gives more green light-enriched irradiance to cells. The cell density-dependent suppression of cell aggregation under blue/green-mixed light and white light conditions support this idea. Such a sensing mechanism may provide information about the cell position in cyanobacterial mats in hot springs, the natural habitat of Thermosynechococcus. This cell position-dependent SesA/B/C-mediated regulation of cellular sessility (aggregation) might be ecophysiologically essential for the reorganization and growth of phototrophic mats. We also report that the green light-induced dispersion of cell aggregates requires red light-driven photosynthesis. Blue/green CBCRs might work as shade detectors in a different niche than red/far-red phytochromes, which may be why CBCRs have evolved in cyanobacteria.

THE EFFECT OF LIGHT QUALITY ON THE PRODUCTS OF PHOTOSYNTHESIS IN CHLORELLA VULGARIS

1962 ◽  
Vol 40 (1) ◽  
pp. 179-189 ◽  
Author(s):  
A. H. W. Hauschild ◽  
C. D. Nelson ◽  
G. Krotkov
Keyword(s):  
Blue Light ◽  
Chlorella Vulgaris ◽  
Glycolic Acid ◽  
Light Quality ◽  
Soluble Fraction ◽  
Red Light ◽  
Total Radioactivity ◽  
Rate Of Photosynthesis ◽  
Effect Of Light

Suspensions of Chlorella vulgaris, grown in synchronous culture, were pretreated in darkness for 45 to 225 minutes and illuminated in the presence of C14-bicarbonate with red, with red plus 4% of blue, and with blue light alone. The light intensities were so adjusted that the rate of photosynthesis (fixation of C14) was the same under the different conditions of illumination. The distribution of C14 among the various compounds of the ethanol-soluble fraction was obtained using paper chromatography and autoradiography.After 5 minutes of photosynthesis, the incorporation of C14 into aspartic acid was higher in the presence of red with supplementary blue light than in red light alone. At the same time the total radioactivity in glycine plus serine and in glycolic acid decreased. After 30 minutes of photosynthesis, blue light supplementary to red and blue light alone increased the total incorporation of C14 into the amino acid plus organic acid fraction as compared with incorporation in red light. This was due mainly to an increase in the radioactivity of aspartic and glutamic acids, while at the same time the radioactivity in glycine and glycolic acid was reduced.The duration of dark pretreatment was an important factor in the 30-minute experiments. The effect of increased dark pretreatment was to lower the incorporation of C14 into aspartic and glutamic acids when photosynthesis was carried out in red light, but the incorporation of C14 into these acids was increased in the presence of supplementary blue light.It is concluded that the distribution of carbon among the products of photosynthesis is affected by the quality of light.

scholarly journals Phototropin 1 and dim-blue light modulate the red light de-etiolation response

2014 ◽  
Vol 9 (11) ◽  
pp. e976158
Author(s):  
Yihai Wang ◽  
Kevin M Folta
Keyword(s):  
Blue Light ◽  
Red Light

scholarly journals Single Wavelengths of LED Light Supplement Promote the Biosynthesis of Major Cyclic Monoterpenes in Japanese Mint

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1420
Author(s):  
Takahiro Ueda ◽  
Miki Murata ◽  
Ken Yokawa
Keyword(s):  
Blue Light ◽  
Solid Phase ◽  
Glandular Trichomes ◽  
Red Light ◽  
Glandular Trichome ◽  
Pulse Amplitude ◽  
Light Treatment ◽  
Led Light ◽  
Trichome Formation ◽  
Japanese Mint

Environmental light conditions influence the biosynthesis of monoterpenes in the mint plant. Cyclic terpenes, such as menthol, menthone, pulegone, and menthofuran, are major odor components synthesized in mint leaves. However, it is unclear how light for cultivation affects the contents of these compounds. Artificial lighting using light-emitting diodes (LEDs) for plant cultivation has the advantage of preferential wavelength control. Here, we monitored monoterpene contents in hydroponically cultivated Japanese mint leaves under blue, red, or far-red wavelengths of LED light supplements. Volatile cyclic monoterpenes, pulegone, menthone, menthol, and menthofuran were quantified using the head-space solid phase microextraction method. As a result, all light wavelengths promoted the biosynthesis of the compounds. Remarkably, two weeks of blue-light supplement increased all compounds: pulegone (362% increase compared to the control), menthofuran (285%), menthone (223%), and menthol (389%). Red light slightly promoted pulegone (256%), menthofuran (178%), and menthol (197%). Interestingly, the accumulation of menthone (229%) or menthofuran (339%) was observed with far-red light treatment. The quantification of glandular trichomes density revealed that no increase under light supplement was confirmed. Blue light treatment even suppressed the glandular trichome formation. No promotion of photosynthesis was observed by pulse-amplitude-modulation (PAM) fluorometry. The present result indicates that light supplements directly promoted the biosynthetic pathways of cyclic monoterpenes.

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

Agronomy ◽  
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.

scholarly journals Guard cells control hypocotyl elongation through HXK1, HY5, and PIF4

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Gilor Kelly ◽  
Danja Brandsma ◽  
Aiman Egbaria ◽  
Ofer Stein ◽  
Adi Doron-Faigenboim ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Blue Light ◽  
Opposite Effect ◽  
Red Light ◽  
Guard Cells ◽  
Cell Types ◽  
Hypocotyl Elongation ◽  
Sugar Production ◽  
Effect Of Light

AbstractThe hypocotyls of germinating seedlings elongate in a search for light to enable autotrophic sugar production. Upon exposure to light, photoreceptors that are activated by blue and red light halt elongation by preventing the degradation of the hypocotyl-elongation inhibitor HY5 and by inhibiting the activity of the elongation-promoting transcription factors PIFs. The question of how sugar affects hypocotyl elongation and which cell types stimulate and stop that elongation remains unresolved. We found that overexpression of a sugar sensor, Arabidopsis hexokinase 1 (HXK1), in guard cells promotes hypocotyl elongation under white and blue light through PIF4. Furthermore, expression of PIF4 in guard cells is sufficient to promote hypocotyl elongation in the light, while expression of HY5 in guard cells is sufficient to inhibit the elongation of the hy5 mutant and the elongation stimulated by HXK1. HY5 exits the guard cells and inhibits hypocotyl elongation, but is degraded in the dark. We also show that the inhibition of hypocotyl elongation by guard cells’ HY5 involves auto-activation of HY5 expression in other tissues. It appears that guard cells are capable of coordinating hypocotyl elongation and that sugar and HXK1 have the opposite effect of light on hypocotyl elongation, converging at PIF4.

The Efficacy of Blue Light versus the Combination of Blue and Red Light Therapy in the Treatment of Acne Vulgaris

2021 ◽  
Author(s):  
Leila Kharazi ◽  
Sahar Dadkhahfar ◽  
Hoda Rahimi ◽  
Mehdi Gheisari ◽  
Nikoo Mozafari ◽  
...  
Keyword(s):  
Blue Light ◽  
Acne Vulgaris ◽  
Red Light ◽  
Light Therapy
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