Featured Research

from universities, journals, and other organizations

Light-emitting diode treatments outperform traditional lighting methods for hydroponically grown tomato plants

Date:
June 23, 2014
Source:
American Society for Horticultural Science
Summary:
Hydroponically grown tomato plants were subjected to three light intensities at three red-to-blue ratio levels and compared to high-pressure sodium, red LED light, a 50:50 LED:HPS mixture, and no supplemental lighting treatments. The highest biomass production -- excluding fruit -- occurred with the 19:1 ratio, whereas a higher fruit production was obtained using the 5:1 ratio. Highest marketable fruit production was obtained with the 50:50 LED:HPS ratio. The 5:1 high treatment performed well in every category.

This is a photo showing an intercanopy view of the LED tomato experimental setup with ripe fruit at McGill University, Macdonald Campus (Ste-Anne-de-Bellevue, QC).
Credit: Mark Lefsrud

In Canada, where outdoor growing seasons are limited, sales from greenhouse fruit and vegetable production operations still surpass $1.1 billion annually. Finding more efficient methods for providing lighting in greenhouse production is a key component to support these high levels of production and increase revenues. "Light irradiance is the limiting factor for increasing production in greenhouses, when all other factors (temperature, nutrient levels, and water availability) are adequately maintained," said the authors of a new study. McGill University researchers Paul Deram, Mark G. Lefsrud, and Valιrie Orsat said that the broad-spectrum high-pressure sodium lamps currently used to provide supplemental lighting for greenhouse are "not the most efficient light source" for greenhouse plant production. The team published the findings of their study aimed at finding alternative lighting options in HortScience.

According to the authors, specific light frequencies in the 400- to 700-nm range have previously been shown to affect photosynthesis more directly than other wavelengths (especially in the red and blue ranges). The researchers designed experiments to determine whether light-emitting diodes (LEDs) could reduce lighting costs in greenhouses. "LEDs can be selected to target the wavelengths used by plants, enabling growers to customize the light produced, to enable maximum plant production and limit wavelengths that do not significantly impact plant growth," they explained.

The scientists subjected hydroponically grown tomato plants to three light intensities at three red-to-blue ratio levels. Secondary lighting treatments used for comparison included 100% high-pressure sodium (HPS), 100% red LED light supplied from above the plant, 100% red LED light supplied below the plant, a 50%:50% LED:HPS mixture, and a control (no supplemental lighting). Both runs of the experiment were implemented for 120 days during two (summer-fall and winter-spring) seasons.

Results showed that the five highest number of fruit-producing light treatments were 5:1 high (385 fruit), 5:1 medium (358 fruit), 5:1 low (341 fruit), 19:1 high (315 fruit), and 100% LED (310 fruit). "Overall, the highest producing LED treatments consistently outperformed the high-pressure sodium treatment alone," the authors said. "These treatments can be considered an improvement over traditional HPS lighting for greenhouses."

Outcomes also revealed that high irradiance levels resulted in the highest vegetative biomass and fruit production for all ratios. The results showed that the highest biomass production (excluding fruit) occurred using the 19:1 ratio, while higher fruit production was obtained using the 5:1 ratio. The highest marketable fruit production resulted from the 50%:50% LED:HPS treatment. The authors said that the 5:1 high treatment performed well in every category.

"As expected from the literature, higher intensities bring forth more production with all ratios producing more under higher irradiance levels," Deram, Lefsrud, and Orsat said. They also determined that an increase in red light increased biomass production and slightly lowered the amount of fruit production. They concluded that LEDs are a "promising mechanism" to enhance greenhouse artificial lighting systems.


Story Source:

The above story is based on materials provided by American Society for Horticultural Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Mark G. Lefsrud, Valιrie Orsat. Supplemental Lighting Orientation and Red-to-blue Ratio of Light-emitting Diodes for Greenhouse Tomato Production. HortScience, June 2014

Cite This Page:

American Society for Horticultural Science. "Light-emitting diode treatments outperform traditional lighting methods for hydroponically grown tomato plants." ScienceDaily. ScienceDaily, 23 June 2014. <www.sciencedaily.com/releases/2014/06/140623131205.htm>.
American Society for Horticultural Science. (2014, June 23). Light-emitting diode treatments outperform traditional lighting methods for hydroponically grown tomato plants. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2014/06/140623131205.htm
American Society for Horticultural Science. "Light-emitting diode treatments outperform traditional lighting methods for hydroponically grown tomato plants." ScienceDaily. www.sciencedaily.com/releases/2014/06/140623131205.htm (accessed October 23, 2014).

Share This



More Plants & Animals News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) — How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) — The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) — Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Family Pleads for Pet Pig to Stay at Home

Family Pleads for Pet Pig to Stay at Home

AP (Oct. 22, 2014) — The Johnson family lost their battle with the Chesterfield County, Virginia Planning Commission to allow Tucker, their pet pig, to stay in their home, but refuse to let the board keep Tucker away. (Oct. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins