Effect of Light Intensity on Rooting and Growth of Hydroponic Strawberry Runner Plants in a LED Plant Factory

To rapidly produce strawberry (Fragaria × ananassa Duch. cv. Benihoppe) transplants from cuttings, suitable light intensities for unrooted runner plants at the rooting stage and rooted runner plants at the seedling stage were determined in a plant factory under LED lighting. At the rooting stage, unrooted runner plants at the 3-leaf stage were hydroponically rooted for 6 days under light intensity of 30, 90, 150, and 210 μmol m−2 s−1, respectively. At the seedling stage, rooted runner plants were hydroponically grown for 18 days under light intensity of 90, 180, 270, and 360 μmol m−2 s−1, respectively. The tube LED lights consisting of white and red LED chips were used as sole light source, and photoperiod was controlled as 16 h d−1. The results showed that the maximum root number (7.7) and longest root length (14.8 cm) of the runner plants were found under 90 μmol m−2 s−1 at the rooting stage. Photosynthetic activity in runner plant leaves under 90 μmol m−2 s−1 were higher than that under 30, 150, and 210 μmol m−2 s−1. Higher light intensity at the range of 90–270 μmol m−2 s−1 increased the stomatal conductance of newly formed leaves of rooted runner plants, thus improving the net photosynthetic rate and growth of rooted runner plants at the seedling stage. The crown diameter, shoot and root dry weights, and root to shoot ratio of rooted runner plants increased by 9.7%, 38.8%, 106.1%, and 48.7%, respectively, when the light intensity increased from 90 to 270 μmol m−2 s−1. However, there was no further improvement of runner plant growth under 360 μmol m−2 s−1. Furthermore, no significant difference of increased dry biomass per mole of photons delivered was found between 180 and 270 μmol m−2 s−1. In consideration of transplant quality and economic balance, light intensity of 90 μmol m−2 s−1 at the rooting stage and 270 μmol m−2 s−1 at the seedling stage were suggested for rapidly producing hydroponic strawberry transplants based on unrooted runner plants in the LED plant factory.

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Larval growth and survival in Indian Butter Catfish, Ompok bimaculatus (Bloch): effect of light intensity and photoperiod

10.1101/623462 ◽

2019 ◽

Author(s):

Kalpana Arambam ◽

Pradyut Biswas ◽

Soibam Khogen Singh ◽

A. B. Patel ◽

Alok Kumar Jena ◽

...

Keyword(s):

Light Intensity ◽

Larval Growth ◽

Maximum Growth ◽

Continuous Darkness ◽

Growth And Survival ◽

Light Intensities ◽

Randomized Design ◽

Significant Difference ◽

Ompok Bimaculatus ◽

Effect Of Light

AbstractTwo sequential indoor rearing trials each of 21 days duration were conducted to investigate the effect of light intensity and photoperiod respectively on the growth and survival of Ompok bimaculatus larvae. In first trial, five different light intensities viz. 0, 300, 500, 900, 1200 lx were applied randomly to 800 larvae (0.003 g; 0.51 cm) stocked in triplicate following a completely randomized design into aquarium (30.0 x 15.0 x 15.0 cm) tanks. Sequentially, in second trial, five photoperiod cycles (light: dark, L: D) namely, 24L: 0D, 16L: 8D, 12L: 12D, 8L: 16D and 0L: 24D in combination with the best performing light intensity (300 lx) as observed from the first trial were employed in triplicates in similar set up. From the first trial, significantly higher survival was observed in 0 and 300 lx, whereas growth was highest in 900 lx (P < 0.05). In the second trial, survival was higher in continuous darkness (0L: 24D), whereas, maximum growth was recorded in 24L: 0D and 16L: 8D groups (P < 0.05). Performance index (PI) showed no significant difference (P > 0.05) among 0 and 300 lx light intensities, but were reduced at higher light intensities. The lowest PI was found in 12L: 12D and 8L: 16D condition but did not have any effect in other photoperiod cycles. Overall, from the present study it can be concluded that growth of the larvae is found to be higher in higher light intensity (900lx) and longer photoperiodic cycles (24L: 0D and 16L: 8D), however, better survival was recorded in total dark conditions suggesting that continuous dark condition is recommended for better hatchery performance of the larvae.

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Photoinactivation of Staphylococcus aureus and Vibrio parahaemolyticus in the model aquatic microcosm: effect of light intensity and dissolved biodegradable organic compound

Water Science & Technology ◽

10.2166/wst.2010.521 ◽

2010 ◽

Vol 62 (8) ◽

pp. 1775-1783 ◽

Cited By ~ 1

Author(s):

Moïse Nola ◽

Armelle G. Simo Matchim ◽

Olga Blanche Mobili ◽

Mireille Nougang ◽

François Krier ◽

...

Keyword(s):

Organic Compound ◽

Light Intensity ◽

Vibrio Parahaemolyticus ◽

Bacterial Species ◽

Polluted Water ◽

Significant Difference ◽

A Cell ◽

Cell Inhibition ◽

The Impact ◽

Effect Of Light

The impact of light (1,000 × 100,000 lx) on the inactivation of S. aureus and V. parahaemolyticus has been assessed under different concentrations of dissolved biodegradable organic compound (BOC) at pH 7.0. First, a gradual decrease in the number of cultivable cells was observed. Secondly, a cell reactivation was observed and it was marked in the absence of BOC. In the absence of BOC, the lowest value of cell inhibition rate (CIR) during the first 3 h was 0.138 h−1 for S. aureus and 0.218 h−1 for V. parahaemolyticus. In the presence of 10,100 and 1,000 mg/l of BOC, it was 0.196 h−1, 0.243 h−1 and 0.257 h−1 for S. aureus respectively, and 0.285 h−1, 0.306 h−1 and 0.409 h−1 for V. parahaemolyticus respectively. The CIRs values of each bacterial species significantly varied (P<0.001) with the changes in BOC concentration. In most cases, no significant difference was noted in the CIRs of both species when they were under the same light intensity and BOC. Nevertheless, it seems important to consider the impact of dissolved BOC during the treatment of bacterial polluted water.

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The effect of light intensity of blinking LED toward coral fishes catch of trap in the waters of Ternate Island

AQUATIC SCIENCE & MANAGEMENT ◽

10.35800/jasm.1.1.2013.1967 ◽

2013 ◽

Vol 1 (1) ◽

pp. 39

Author(s):

Janhar Al Ammari

Keyword(s):

Light Intensity ◽

Block Design ◽

High Light Intensity ◽

Moon Phase ◽

Randomized Block Design ◽

Species Analysis ◽

Significant Difference ◽

Control Light ◽

And Control ◽

Effect Of Light

Using blinking Light Emiting Diode (LED) could increase the fishing power of bottom traps. The objective of this research was to study the effect of light intensity of LED (blinking lamp) inside the trap and moon phase toward the capture of coral fishes. Three light intensities of LED were used: 35 lux (2 LED), 70 lux (4 LED), 105 lux (6 LED) and one without blinking lamp as a control. Catch data were collected using 12 units of bottom traps operating in coral waters of Ternate Island at depths around 5 to 7 m.Data analysis wasdone based on randomized block design. The catch was 181 fish in total comprising 12 families, 17 genera and 28 species. Analysis of variance showed that using different light intensity of LED on bottom traps and different moon phase caused highly significant effect in catch. Least significant differences test showed that using light intensity 105 lux (6 LED) inside the trap is not significant in catch to 70 lux (4 LED), but highly significant to 35 lux (2 LED) and control. Light intensity 70 lux (4 LED) is not significant in catch to 35 lux (2 LED), but highly significant to control. There was no significant difference between light intensity 70 lux (4 LED) and control. Catch of trap could increase when using higher light intensity of blinking lamp (LED) and the catch of trap also increase when operated around dark moon. It is better to use high light intensity of blinking lamp (105 lux) inside the trap, and operated in dark moon to catch coral fishes© Penggunaan lampu LED (Ligh Emiting Diode) berkedip didalam bubu diduga dapat meningkatkan kemampuan tangkap. Penelitian ini bertujuan untuk mempelajari pengaruh intensitas cahaya lampu LED berkedip di dalam bubu dan fase umur bulan terhadap hasil tangkapan ikan-ikan karang. Tiga jenis intensitas cahaya lampu yang digunakan, yaitu 35 lux (2 LED), 70 lux (4 LED), 105 lux (6 LED), dan lampu LED tanpa berkedip sebagai kontrol. Data dikumpulkan dengan mengoperasikan 12 unit bubu di perairan karang Pulau Ternate pada kedalaman sekitar 5–7 m; dan dianalisis berdasarkan Rancangan Acak Kelompok. Hasil tangkapan total sebanyak 181 ekor; terdiri dari 15 famili, 25 genus, dan 35 jenis. Analisis sidik ragam menunjukkan bahwa perbedaan intensitas cahaya lampu LED dalam bubu dan perbedaan fase umur bulan berpengaruh sangat nyata terhadap hasil tangkapan. Hasil uji BNT untuk perlakuan menunjukkan bahwa penggunaan lampu 6 LED (105 lux) pada bubu tidak berbeda nyata dengan penggunaan lampu 4 LED (70 lux) tetapi berbeda sangat nyata dengan penggunaan lampu 2 LED (35 lux) dan Kontrol. Demikian juga lampu 4 LED tidak berbeda nyata dengan lampu 2 LED tetapi berbeda sangat nyata dengan Kontrol; sedangkan antara lampu 2 LED dan Kontrol tidak ada perbedaan yang nyata. Hasil tangkapan bubu meningkat ketika menggunakan lampu kedip dengan intensitas yang lebih tinggi; dan dioperasikan pada saat bulan gelap. Sebaiknya menggunakan lampu LED berkedip 105 lux dan dioperasikan saat bulan gelap untuk menangkap ikan-ikan karang dengan bubu©

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Light intensity and photoperiod influence the growth and development of hydroponically grown leaf lettuce in a closed-type plant factory system

Horticulture Environment and Biotechnology ◽

10.1007/s13580-013-0109-8 ◽

2013 ◽

Vol 54 (6) ◽

pp. 501-509 ◽

Cited By ~ 56

Author(s):

Jeong Hwa Kang ◽

Sugumaran KrishnaKumar ◽

Sarah Louise Sua Atulba ◽

Byoung Ryong Jeong ◽

Seung Jae Hwang

Keyword(s):

Light Intensity ◽

Growth And Development ◽

Closed Type ◽

Plant Factory ◽

Hydroponically Grown ◽

Leaf Lettuce

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Morphological and Physiological Responses of Cucumber Seedlings to Supplemental LED Light under Extremely Low Irradiance

Agronomy ◽

10.3390/agronomy10111698 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1698

Author(s):

Yiting Zhang ◽

Hao Dong ◽

Shiwei Song ◽

Wei Su ◽

Houcheng Liu

Keyword(s):

Light Intensity ◽

Leaf Area ◽

Soluble Sugar ◽

Red Light ◽

Seedling Stage ◽

Stem Diameter ◽

Growth Stages ◽

Led Light ◽

Cucumber Seedlings ◽

Red Led

In order to inhibit spindling growth and improve quality of cucumber seedlings under low irradiance, effects of supplemental light-emitting diodes (LED) light (SL) on morphological and physiological characteristics of cucumber seedlings at different growth stages under extremely low irradiance (ELI) were investigated. Supplementary monochromatic, dichromatic and trichromatic LED light on cucumber seedlings were conducted in experiment one, and supplements of combination ratios and intensity of blue and red LED light (RB) were conducted in experiment two. The morphological and physiological parameters of cucumber seedlings were promoted effectively by supplemental monochromatic red light or dichromatic containing red light (RB and RG) under ELI as early as one-leaf seedling stage, as demonstrated by suppressed length of hypocotyl and first internode, increased stem diameter and biomass, higher net photosynthetic rate (Pn) and soluble sugar content. Monochromatic or additional green light was not beneficial to cucumber seedlings under the ELI. The length of shoot and hypocotyl decreased, while stem diameter and leaf area increased as early as one-leaf seedling stage by RB SL. Root activities, root–shoot ratio, activities of catalase (CAT) and peroxidase (POD), as well as palisade–spongy ratio in the leaf of cucumber seedlings were promoted effectively by increasing blue light proportion (1R1B/1R2B). Increasing light intensity (50/75) enhanced soluble sugar accumulation in leaves. There were synergistic effects of RB ratio and light intensity on increasing stem diameter, leaf area, seedling index and decreasing hypocotyl cell area of the vertical section. In conclusion, 1R2B-75 may be the optimal SL to inhibit spindling growth of cucumber seedlings under ELI condition.

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Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103565 ◽

1988 ◽

Vol 46 ◽

pp. 300-301

Author(s):

C. S. Bricker ◽

S. R. Barnum ◽

B. Huang ◽

J. G. Jaworskl

Keyword(s):

Fatty Acid ◽

Light Intensity ◽

Acid Content ◽

Fatty Acid Content ◽

Anabaena Variabilis ◽

Chloroplast Envelope ◽

Major Constituent ◽

Filamentous Cyanobacterium ◽

Photosynthetic Membrane ◽

Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

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