Nav: Home

How LED lighting treatments affect greenhouse tomato quality

December 21, 2015

WEST LAFAYETTE, IN - To satisfy increasing consumer demand for locally grown, fresh tomatoes during off-seasons, greenhouse tomato growers often need to rely on supplemental lighting. Tomato growers are looking to light-emitting diodes (LEDs), favored for their energy-saving potential, as an alternative to high-pressure sodium lamps (HPS) in greenhouse operations. A recent study offers new information about the feasibility of using LEDs in greenhouse tomato operations.

Michael Dzakovich, Celina Gómez, and Cary Mitchell from the Department of Horticulture and Landscape Architecture at Purdue University published the study of supplemental lighting experiments in HortScience (October 2015). They noted that light-emitting diodes are becoming a viable alternative to high-pressure sodium supplementation. "There is great interest in (LEDs) potential to influence the phytochemical and flavor profile of various high-value crops," the authors said. "However, little fruit quality-attribute work with LEDs has been done on a long-duration, full grow-out of tomatoes."

The researchers conducted three separate studies to investigate the effect of supplemental light quantity and quality on greenhouse-grown tomatoes. Plants were grown either with natural solar radiation only (the control), natural solar radiation plus supplemental lighting from high-pressure sodium lamps, or natural solar radiation plus supplemental light from intracanopy (IC) LED towers. The scientists analyzed plant responses by collecting chromacity, Brix, titratable acidity, electrical conductivity, and pH measurements. "Contrary to our hypothesis, fruit quality was largely unaffected by direct, IC supplemental lighting," the authors said.

The study also included sensory panels in which tasters ranked tomatoes for color, acidity, and sweetness using an objective scale. The tasters were also asked to rank tomato color, aroma, texture, sweetness, acidity, aftertaste, and overall approval using a five-point hedonic (preference) scale. "By collecting both physicochemical and sensory data, we were able to determine whether statistically significant physicochemical parameters of tomato fruit also reflected consumer perception of fruit quality," the authors said. The sensory panels indicated that physicochemical differences were not noticeable to tasters; in fact, the tasters on the testing panels could not discern between tomatoes from different supplemental lighting treatments or those from the unsupplemented controls.

"This study demonstrated that greenhouse tomato fruit quality was unaffected by both the type of supplemental lighting as well as supplemental lighting per se," the scientists said. "Physicochemical measurements indicated only slight variation among fruits grown under different lighting regimes, and these findings were supported by nonsignificant differences in sensory attributes."

The authors said the results are promising for tomato growers interested in reducing energy consumption in greenhouses. "Supplemental IC-LED lighting at the intensities and wavelengths used in this study did not negatively affect greenhouse tomato fruit quality and demonstrates a potential alternative for overhead high-pressure sodium supplementation," they said.
-end-
The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/content/50/10/1498.abstract

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at ashs.org

American Society for Horticultural Science

Related Greenhouse Articles:

Making microbes that transform greenhouse gases
A new technique will help not only reduce greenhouse gas emissions, but the potential to reduce the overall dependence on petroleum.
Reducing greenhouse gases while balancing demand for meat
Humans' love for meat could be hurting the planet. Many of the steps involved in the meat supply chain result in greenhouse gas emissions.
Degrading plastics revealed as source of greenhouse gases
Researchers from the University of Hawai'i at Mānoa School of Ocean and Earth Science and Technology (SOEST) discovered that several greenhouse gases are emitted as common plastics degrade in the environment.
Wandering greenhouse gas
On the seafloor of the shallow coastal regions north of Siberia, microorganisms produce methane when they break down plant remains.
Thawing permafrost releases old greenhouse gas
The thawing permafrost soils in the Arctic regions might contribute to the greenhouse effect in two respects: on the one hand rising temperatures lead to higher microbial methane production close to the surface.
Greenhouse gases: First it was cows -- now it's larvae!
Scientists at UNIGE have discovered that Chaoborus spp uses the methane it finds in lakebeds to help it move around.
Researchers discover greenhouse bypass for nitrogen
An international team discovers that production of a potent greenhouse gas can be bypassed as soil nitrogen breaks down into unreactive atmospheric N2.
Reservoirs are a major source of greenhouse gases
The BioScience Talks podcast (http://bioscience.libsyn.com) features discussions of topical issues related to the biological sciences
Reservoirs are a major source of greenhouse gases
Dammed rivers are often considered environmentally friendly, carbon-neutral energy sources, but the reservoirs they create release large amounts of greenhouse gases to the atmosphere.
'Watchdog' for greenhouse gas emissions
Mistakes can happen when estimating emissions of greenhouse gases such as carbon dioxide and methane.
More Greenhouse News and Greenhouse Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.