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Cassandra M. Plank, Edward W. Hellman, and Thayne Montague

, shaded by canopy, or shaded by canopy with supplemental light-emitting diode (LED) light. Exposure occurred in preveraison (fruit set to 50 d postanthesis), postveraison (veraison to harvest), and postveraison under a continuous shoot growth during 3

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Hsing-Ying Chung, Ming-Yih Chang, Chia-Chyi Wu, and Wei Fang

lighting primarily use light from white light-emitting diodes (LEDs) as the light source for cultivation; however, these light sources do not emit ultraviolet light, and the spectra are considerably different from sunlight. Previous studies have mentioned

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Celina Gómez and Cary A. Mitchell

for each of three supplemental lighting (SL) treatments [600 W top high-pressure sodium lamps (HPS) versus intracanopy light-emitting diode (ICL-LED) vertical towers versus hybrid lighting (350 W top HPS lamps + horizontal ICL-LEDs)] used for the

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Allison Hurt, Roberto G. Lopez, and Joshua K. Craver

light-emitting diode (LED_70) lamps at a photosynthetic photon flux density ( PPFD ) of 70 µmol·m –2 ·s –1 ; supplemental lighting based on an instantaneous threshold (on from 0600 to 2200 hr when outside PPFD was less than ≈440 µmol·m –2 ·s –1

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Qingwu Meng, Jennifer Boldt, and Erik S. Runkle

-stature crops, such as leafy greens and herbs, are common crop types that are suitable for commercial indoor vertical farming ( Kozai et al., 2015 ). Light-emitting diodes (LEDs) are the predominant light source of indoor vertical production systems because they

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Kazuhiro Fujiwara, Toshinari Sawada, Yoshikatsu Kimura, and Kenji Kurata

A light-emitting diode (LED)-low light irradiation (LLI) storage system was developed for suppressing the change in dry weight and maintaining the quality of green plants during long-term storage. In this system, the carbon dioxide (CO2) exchange rate was maintained at zero by automatically adjusting the photosynthetic photon flux density (PPFD) with a proportional-integralderivative (PID) controller. The voltage supplied to the LEDs was controlled by the difference between the inflow (400 μmol·mol-1) and outflow CO2 concentrations in the storage case. Grafted tomato (Lycopersicon esculentum; scion = `House Momotaro'; rootstock = `Anchor T') plug seedlings were stored at 10 °C for 35 days under four different LLI conditions as a system operating test: fixed red light irradiation at 2 μmol·m-2·s-1, PID-controlled red light irradiation with no blue light, and PID-controlled red light irradiation with blue light at 0.2 or 1.0 μmol·m-2·s-1. The results showed that the automatic PPFD control during LED-LLI helped suppress changes in dry weight during storage as expected. Furthermore, it was found that addition of a low percentage of blue light improved the morphological appearance of the seedlings and reduced the PPFD required to suppress the change in dry weight.

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Gary W. Stutte

illustrates the exponential increase in research for the 25-year period from 1990 to 2015. A general online search using criteria {“Light emitting diodes” and “Horticulture”} on a widely used digital search engine limited to academic sources ( scholar

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Joshua K. Craver, Krishna S. Nemali, and Roberto G. Lopez

With the development of light-emitting diodes (LEDs) and advancements in environmental control technologies, indoor production using sole-source lighting (SSL) is a potential alternative to traditional greenhouse production for many high

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Shih-Wei Kong, Hsin-Ying Chung, Ming-Yi Chang, and Wei Fang

low absorptivity coefficient in the absorption spectra of purified chlorophylls ( Sun et al., 1998 ). Light-emitting diodes (LEDs) allow production of light that emit only the wavelengths of light corresponding to the absorption peaks of plant

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Cary A. Mitchell

Barta, D.J. Tibbitts, T.W. Bula, R.J. Morrow, R.C. 1992 Evaluation of light emitting diode characteristics for a space-based plant irradiation source Adv. Space Res. 12 141 149 Blaauw, O. Blaauw-Jansen, G. 1970 The phototropic responses of Avena