Featured Research

from universities, journals, and other organizations

Solid-state illuminator reduces nitrates in leafy green vegetables

Date:
April 26, 2010
Source:
American Society for Horticultural Science
Summary:
Searching for ways to improve the nutritional quality of leafy green vegetables, Lithuanian researchers have found success with new technology that features high-density photosynthetic photon flux generated by a solid-state illuminator. The technology, which can be applied in greenhouses for preharvest treatment of leafy vegetables, was found to decrease concentrations of harmful nitrates while allowing some beneficial nutrient levels to increase.

Green onions subjected to red LED treatment during the experiment showed a decrease in nitrates.
Credit: Photo by Akvile Urbonaviciute

Searching for ways to improve the nutritional quality of leafy green vegetables, Lithuanian researchers have found success with new technology that features high-density photosynthetic photon flux generated by a solid-state illuminator. The technology, which can be applied in greenhouses for preharvest treatment of leafy vegetables, was found to decrease concentrations of harmful nitrates while allowing some beneficial nutrient levels to increase.

The research results were published in a recent issue of HortScience.

The researchers experimented with a solid-state illuminator to provide short-term preharvest light treatment of lettuce, marjoram, and green onions. The vegetable plants were grown to harvest time in a greenhouse under daylight with supplementary lighting provided by standard high-pressure sodium lamps. A subsequent 3-day treatment within a phytotron under light-emitting diodes resulted in the reduction of nitrate concentration by 44% to 65%.

According to Giedre Samuoliene, lead author of the report, the technology is different from the usual practice of using high-pressure sodium lamps; solid-state illuminators limit the amount of radiant heat, allowing a high intensity of photosynthesis. Additionally, the technique allows for short-term treatment of plants rather than for full-cycle growth.

In vegetable leaves exposed to light generated by the solid-state illuminator, nitrate concentration was reduced by two to three times in comparison with those kept under high-pressure sodium lamps. The highest nitrate reduction rate was observed in hydroponically grown lettuce; after a 3-day treatment under red LEDs, tests showed a 65% relative decrease of nitrate concentration. The relative decrease of nitrates was similar in all species tested. "The results of our study indicate that nitrate content in lettuce, marjoram, and green onions can be considerably reduced by several times using short-term preharvest treatment under purely red light with high PPFD," stated Samuoliene.

A significant outcome of the research is the finding that leafy vegetables can be produced under normal lighting conditions, while the health quality can be improved with a relatively short treatment using an advanced solid-state illuminator. The new technology may be expensive, but can prove economically viable in terms of production costs and the benefits of vegetables with added nutritional value. Since the treatment is conducted only over 10% of the overall growth cycle, the capital cost limitations for the application of solid-state lighting in horticulture are mitigated.

The researchers noted that the technology may be particularly practical for leafy vegetable production in northern countries where greenhouse plants are often grown under poor lighting conditions.


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. Samuoliene, Giedre, Urbonaviciute, Akvile, Duchovskis, Pavelas, Bliznikas, Zenonas, Vitta, Pranciskus, Zukauskas, Arturas. Decrease in Nitrate Concentration in Leafy Vegetables Under a Solid-state Illuminator. HortScience, 2009; 44: 1857-1860

Cite This Page:

American Society for Horticultural Science. "Solid-state illuminator reduces nitrates in leafy green vegetables." ScienceDaily. ScienceDaily, 26 April 2010. <www.sciencedaily.com/releases/2010/04/100415185814.htm>.
American Society for Horticultural Science. (2010, April 26). Solid-state illuminator reduces nitrates in leafy green vegetables. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2010/04/100415185814.htm
American Society for Horticultural Science. "Solid-state illuminator reduces nitrates in leafy green vegetables." ScienceDaily. www.sciencedaily.com/releases/2010/04/100415185814.htm (accessed April 18, 2014).

Share This



More Plants & Animals News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
Powered by NewsLook.com
Flamingo Frenzy Ahead of Zoo Construction

Flamingo Frenzy Ahead of Zoo Construction

AP (Apr. 17, 2014) With plenty of honking, flapping, and fluttering, more than three dozen Caribbean flamingos at Zoo Miami were rounded up today as the iconic exhibit was closed for renovations. (April 17) Video provided by AP
Powered by NewsLook.com
Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
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:
from the past week

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