LIGHT AND TEMPERATURE EFFECTS ON GROWTH AND SPOROPHORE FORMATION OF LENZITES TRABEA

1967 ◽  
Vol 45 (4) ◽  
pp. 525-530
Author(s):  
C. Madhosingh
Keyword(s):  
Temperature Effects ◽  
Growth Form ◽  
Red Light ◽  
Vegetative Mycelium ◽  
Temperature Growth ◽  
Low Intensity ◽  
Morphological Studies ◽  
Brown Pigmentation ◽  
Yellow Pigments ◽  
Red Radiation

Growth, pigmentation, and sporophore formation in Lenzites trabea, a polypore fungus, are shown to be affected by differences in light and temperature. Growth occurred under all conditions provided, being greater on liquid substrate than on agar and with maximum mycelium production in continuous red light at 25 °C. Sporophores, however, were formed only under certain continuous fluorescent and red radiations on liquid substrate; and on agar at 15 °C, 20 °C, and 25 °C in darkness broken by occasional brief exposures to low intensity daylight. The growth form under the red radiation and in darkness at 25 °C was similar. The form of fructification varied from poroid resupinate at 15 °C, to somewhat raised structures with larger pores at 20 °C, to an assemblage of discrete upright bodies with lacerated surface at 25 °C. Yellow-brown pigmentation was consistently associated with the fruiting areas in contrast with the predominantly fawn-yellow pigments of the vegetative mycelium. The significance of these results in comparative morphological studies is discussed.

scholarly journals Effects of Low Intensity Red Light on Testicular Recrudescence in Japanese Quail

1981 ◽  
Vol 60 (2) ◽  
pp. 453-461 ◽  
Author(s):  
R.P. GILDERSLEEVE ◽  
W.A. JOHNSON
Keyword(s):  
Japanese Quail ◽  
Red Light ◽  
Low Intensity ◽  
Testicular Recrudescence

scholarly journals The Use of Plastic Films and Sprayable Reflective Particle Films to Increase Light Penetration in Apple Canopies and Improve Apple Color and Weight

HortScience ◽  
2007 ◽  
Vol 42 (1) ◽  
pp. 91-96 ◽  
Author(s):  
D. Michael Glenn ◽  
G.J. Puterka
Keyword(s):  
Red Light ◽  
Fruit Weight ◽  
The West ◽  
Dry Matter Partitioning ◽  
West Side ◽  
Plastic Films ◽  
Beneficial Effects ◽  
Reflected Light ◽  
Red Color ◽  
Red Radiation

The objective of the present study was to examine the effect of a reflective, aluminized plastic film (APF), a reflective, particle-based film applied to the tree (PFT), a reflective, particle film applied to the west side of the tree (PFW), or a particle-based reflective film applied to the grass between tree rows (RPF) on ‘Empire’ apple [Malus domestica (Borkh.)] color and fruit weight in a multiyear study. The APF treatment consistently increased red color and was the only treatment to increase fruit red color from the lower portion of the west side of the tree. The PFT, PFW, and RPF treatments inconsistently improved apple red color. The APF treatment reflected ≈6 times the amount of photosynthetically active radiation (PAR) as the RPF and reflected different red/far-red light ratios (R/FR). In all years, average fruit weight was increased by the RPF, PFT, and PFW treatments compared with the untreated control and APF treatment. The mechanism responsible for the increased fruit weight may be the altered light quality, not quantity, reflected from the RPF treatments. The reflected light has enhanced far-red radiation, which may have beneficial effects on both fruit color and fruit weight. The effect of enhanced far-red radiation on increased fruit weight may be a phytochrome-mediated process affecting dry matter partitioning.

scholarly journals Low-intensity, Long-wavelength Red Light Slows the Progression of Myopia in Children: an Eastern China-based Cohort

2021 ◽  
Author(s):  
Lei Zhou ◽  
Chao Xing ◽  
Wei Qiang ◽  
Chaoqun Hua ◽  
Liyang Tong
Keyword(s):  
Eastern China ◽  
Red Light ◽  
Spectral Composition ◽  
Enhanced Depth Imaging ◽  
Myopia Progression ◽  
Short Treatment ◽  
Binary Images ◽  
Low Intensity ◽  
Ambient Lighting ◽  
East And Southeast Asia

Abstract Myopia is prevalent worldwide, particularly in East and Southeast Asia. Recent studies have suggested that the spectral composition of ambient lighting influences refractive development, especially in humans. We aimed to determine the effect of 650-nm single-wavelength red light on the inhibition of myopia progression in children. In this retrospective cohort study, 105 myopic children (spherical equivalent refractive error [SER], -6.75 to -1.00 dioptres (D)) aged from 4 to 14 years old were retrospectively reviewed. Subjects were treated with 650-nm, low-intensity, single-wavelength red light twice a day for 3 minutes each session, with at least a 4-hour interval between sessions. IOL Master was utilized to measure the axial length (AL) and corneal curvature. Choroidal images were assessed using enhanced depth imaging optical coherence tomography (EDI-OCT), and the luminal area (LA) and stromal area were converted to binary images by the Niblack method. At baseline, the mean SER was -3.09 ± 1.74 D and -2.87 ± 1.89 D at 9 months, and significant changes occurred over time (P = 0.019). The AL increased by -0.06 ± 0.19 mm for 9 months (0.21 ± 0.15 mm pretreatment; P＜0.001). The subfoveal choroidal thickness (SFChT) had changed by 45.32 ± 30.88 μm at the 9-month examination (P＜0.001). Repetitive exposure to 650-nm, low-intensity, single-wavelength red light effectively slowed the progression of myopia and reduced axial growth after short treatment durations. These results require further validation in a longitudinal study, as well as further research in animal models.

scholarly journals 568 Effect of Twilight and Temperature Difference (DIF) or Temperature Pulse at End-of-day on Height of Easter Lilies

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 544C-544
Author(s):  
Theo J. Blom ◽  
David Kerec
Keyword(s):  
Plant Height ◽  
Temperature Difference ◽  
Lilium Longiflorum ◽  
Light Period ◽  
Night Temperature ◽  
Temperature Pulse ◽  
Low Intensity ◽  
Snow White ◽  
Significant Difference ◽  
Red Radiation

Potted bulbs of Lilium longiflorum Thunb. `Ace', `Nellie White', and `Snow White' were grown under either ambient photo period (APP), 8-h photo period using blackout (no twilight) between 1600 and 0800 HR (8PP) or 8PP extended with 1-h of low-intensity far-red radiation (9PP) at end-of-light period in a greenhouse with either a +5 °C DIF or a –5 °C DIF (= day – night temperature). In a second experiment, Easter lilies were also grown under APP, 8PP, and 9PP regimes with a constant day/night temperature (0 °C DIF) but with either a +5 °C or –5 °C temperature pulse for 3-h during end-of-light period. Each experiment was replicated twice and data was averaged over 2 years. The +5 °C DIF regime produced plants which were 19% taller than under –5 °C DIF. Plants grown under APP were 32% and 25% taller than under 8PP in the +5 °C and –5 °C DIF regimes, respectively. Regardless of the DIF regime, plant height under the 9PP was the same. In the second experiment, there was no significant difference in plant height of plants grown with the –5 °C compared with the +5 °C pulse at end-of-light period.

scholarly journals Supplementary Far-Red Light Did Not Affect Tomato Plant Growth or Yield under Mediterranean Greenhouse Conditions

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1849
Author(s):  
Onofrio Davide Palmitessa ◽  
Beniamino Leoni ◽  
Francesco Fabiano Montesano ◽  
Francesco Serio ◽  
Angelo Signore ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Plant Growth ◽  
Fruit Quality ◽  
Light Emitting Diode ◽  
Red Light ◽  
Growth Yield ◽  
Fruit Production ◽  
F1 Hybrid ◽  
Light Emitting ◽  
Red Radiation

In the Mediterranean region, tomato plants are often cultivated in two short cycles per year to avoid the heat of summer and the low solar radiation of winter. Supplementary light (SL) makes it possible to cultivate during the dark season. In this experiment, a tomato F1 hybrid cultivar DRW7723 was cultivated in a greenhouse for a fall-winter cycle. After transplant, light emitting diode (LED) interlighting, with two light spectra (red + blue vs. red + blue + far-red) was applied as SL. Plant growth, yield, gas exchange, nutrient solution (NS) consumption, and fruit quality were analyzed. In general, the effects of adding far-red radiation were not visible on the parameters analyzed, although the yield was 27% higher in plants grown with SL than those grown without. Tomatoes had the same average fresh weight between SL treatments, but the plants grown with SL produced 16% more fruits than control. Fruit quality, gas exchange and NS uptake were not influenced by the addition of far-red light. Interlighting is, therefore, a valid technique to increase fruit production in winter but at our latitude the effects of adding far-red radiation are mitigated by available sunlight.

Study of photobiomodulation effects with violet-blue and red light in experimental oncogenesis

2020 ◽  
Vol 60 (9) ◽  
pp. 618-623
Author(s):  
Evgeniya S. Zhukova ◽  
Tatiana G. Shcherbatyuk ◽  
Arseniy L. Potapov ◽  
Irina A. Chernigina ◽  
Vladimir V. Chernov ◽  
...  
Keyword(s):  
Free Radical ◽  
Tumor Growth ◽  
Electromagnetic Radiation ◽  
Electromagnetic Waves ◽  
Biological Effects ◽  
Red Light ◽  
Free Radical Processes ◽  
Low Intensity ◽  
Radical Processes

Introduction. There is still an open question about the limits of medical use of low-intensity electromagnetic radiation of the optical range in tumor growth due to the risk of increased proliferation of tumor cells. The conditions under which the tumor process is stimulated, as well as the mechanisms of photobiomodulation in oncological pathology, remain unclear. The aim of the study - in vitro evaluation and comparison of the effect of low-intensity electromagnetic radiation with wavelengths of 400, 460 and 660 nm on the activity of free-radical processes in tumor tissue and blood in normal and growing experimental neoplasia. Materials and methods. The study was conducted on biological material obtained from white non-linear rats intact and with subcutaneously transplanted cholangiocellular cancer MS-1. The sources of low-intensity radiation with wavelengths of 400, 460 and 660 nm were led generators. The content of hemoglobin, the activity of superoxide dismutase and catalase, changes in the overall level of free radical processes and antioxidant activity by induced chemiluminescence, and DNA damage by the method of DNA comets were studied. Data analysis was performed using nonparametric statistics methods. Results. The multidirectional effect of radiation with wavelengths of 400, 460 and 660 nm on free-radical homeostasis indicators at the early and late stages of tumor growth, as well as the dependence of biological effects on the wavelength of radiation, was found. Conclusions. The results obtained allow making a number of assumptions about the mechanisms of action of the optical electromagnetic waves on tumor growth, modulating free radical processes in the tumor-bearing organism.

scholarly journals Blue and red light effects on stomatal oscillations

2019 ◽  
Vol 46 (2) ◽  
pp. 146 ◽  
Author(s):  
Trevor Ballard ◽  
David Peak ◽  
Keith Mott
Keyword(s):  
Blue Light ◽  
Guard Cell ◽  
Red Light ◽  
Guard Cells ◽  
Surrounding Tissue ◽  
Single Pair ◽  
Fibre Optic ◽  
Fibre Optics ◽  
Cell Pair ◽  
Low Intensity

The response of stomata to red and blue light was investigated using small fibre optics (66µm diameter) to control light levels on a single pair of guard cells without affecting the surrounding tissue. Low intensity red light (50µmolm–2s–1) applied to the entire leaf caused stomata to oscillate continuously for several hours with no apparent decrease in amplitude with time. Adding low intensity blue light (50µmolm–2s–1) caused stomata to stop oscillating, but oscillations resumed when the blue light was removed. Adding the same intensity of red light to an oscillating leaf changed the amplitude of the oscillations but did not stop them. When blue light was added to a single guard cell pair (using a fibre optic) in a red-light-illuminated leaf, the stoma formed by that pair stopped oscillating, but adjacent stomata did not. Red light added to a single guard cell pair did not stop oscillations. Finally, blue light applied through a fibre optic to areas of leaf without stomata caused proximal stomata to stop oscillating, but distal stomata continued to oscillate. The data suggest that blue light affects stomata via direct effects on guard cells as well as by indirect effects on other cells in the leaf.

Smallseed Dodder (Cuscuta planiflora) Phototropism toward Far-red When in White Light

Weed Science ◽  
1996 ◽  
Vol 44 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Gregory L. Orr ◽  
Mustapha A. Haidar ◽  
Deborah A. Orr
Keyword(s):  
Blue Light ◽  
Potassium Iodide ◽  
White Light ◽  
Host Location ◽  
Red Light ◽  
Infra Red ◽  
Red Radiation

White light-grown seedlings of smallseed dodder were (a) provided with unilateral far-red (700 to 800 nm) at photon irradiances ranging from 20 to 110 μmol m−2s−1against a background of cool white light (400 to 700 nm) from above at 77 μmol m−2s−1, or (b) transferred to darkness and provided with unilateral white light at 20 μmol m−2s−1, unilateral blue light (400 to 500 nm) at 10 μmol m−2s−1, unilateral red light (600 to 700 nm) at 10 μmol m−2s−1, unilateral far-red at 50 μmol m−2s−1, or (c) in experiments utilizing bilateral irradiations, provided with unilateral far-red perpendicular to unilateral white light. Positive phototropic curvature was induced by unilateral white light and by unilateral blue light in otherwise darkness and by unilateral far-red in a background of cool white light. Seedling vines were also phototropic toward unilateral far-red when provided with unilateral white light perpendicular to unilateral far-red. Phototropism to unilateral white light was inhibited in seedlings treated with 200 μM norflurazon and 50 mM potassium iodide. Norflurazon- and potassium iodide-treated seedlings remained phototropic toward unilateral far-red when provided with unilateral white light perpendicular to unilateral far-red. Seedling vines were not phototropic to unilateral red or to unilateral far-red in otherwise darkness, and seedlings in cool white light were neither skototropic (i.e., tropic toward unilateral darkness) nor tropic to or from infra-red (radiation with wavelengths greater than 900 nm). Phototropism toward regions of lowered red:far-red may aid smallseed dodder in chlorophyllous host location and attachment.

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