outer leaves senesce fast and appear yellow ( McCabe et al., 2001 ), resulting in large reductions in plant yield at the time of shipment. A recent study indicated that supplemental upward lighting from underneath the plants could delay the senescence of
growth. The type, spectra, intensity, and timing of supplemental lighting can each have a large influence on the effects of light on plants ( Choong et al., 2018 ; Craig and Runkle, 2016 ; Demotes-Mainard et al., 2016 ; Gomez and Mitchell, 2015
yield and quality of vegetables can be achieved only by using supplemental lighting ( Dorais et al., 1991 ; McAvoy and Janes, 1984 ; Rodriguez and Lambeth, 1975 ; Tibbitts et al., 1987 ). However, the use of supplemental lighting represents an expense
depend on the intended transplant use, because morphological preferences for scions, rootstocks, or non-grafted production seedlings are different ( Chia and Kubota, 2010 ). Supplemental lighting promotes growth of greenhouse-grown vegetable seedlings by
supplemental and photoperiodic lighting sources logged every hour by a data logger (model CR1000; Campbell Scientific, Logan, UT). Data were collected under continuous supplemental lighting with a 16-h photoperiod provided by high-pressure sodium (HPS_70) or
latitudes must compensate for the attenuation in total light availability (from prolonged winter with short daylight hours), and supplemental artificial lighting is required to maintain a consistent crop yield throughout the Canadian winters. Conventional
February ( Korczynski et al., 2002 ). Supplemental lighting is often needed to produce high-quality crops in controlled-environment agriculture but can substantially increase production costs. For example, van Iersel and Gianino (2017) estimated that the
providing supplemental lighting. These lights are expensive to use. Combining the ballast and bulb, a single 400-W HPS light consumes ≈465 W of electrical energy ( Nelson, 2003 ). To provide supplemental light at a PPF of ≈85 μmol·m −2 ·s −1 requires
. Misc. Collect. 95 21 564 569 Hurt, A. Lopez, R.G. Craver, J.K. 2019 Supplemental but not photoperiodic lighting increased seedling quality and reduced production time of annual bedding plants HortScience 54 289 296 10.21273/HORTSCI13664-18 Inada, K
Light is one of the limiting factors for plant growth. To increase the PPF for plant growth, greenhouse growers must supplement solar light with electric-powered light. The most common lighting technology used to increase PPF in the greenhouse