Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rotating high-pressure sodium lamps provide flowering plants for spring markets

21.09.2010
Intermittent light system more cost-effective than incandescent illumination

When consumers visit garden centers in spring they will most likely buy flowering ornamental plants that are ready for their home gardens. Studies have shown that consumers favor plants that are already in flower rather than those that are "vegetative"—a preference that can present multiple challenges for commercial growers.

To satisfy consumers' wishes, producers of ready-to-flower ornamentals like bedding plants and perennials start growing crops far in advance of the spring buying season, often during the dark and short days of winter. When the days are short, commercial growers turn to "light manipulation" techniques that either promote or prevent flowering in preparation for delivery to markets. New research from a team at Michigan State University offers commercial plant producers a cost-effective method for producing market-ready plants that appeal to both consumers and retailers.

"Long-day" plants are varieties in which flowering is promoted under short periods of darkness, whereas "short-day" plants flower when the dark period exceeds a critical duration. To satisfy spring markets, some commercial ornamental growers create artificial long-day (LD) environments to produce flowering plants for delivery to retailers. Growers employ several methods to promote flowering in LD plants under natural short photoperiods. Methods include extending day length with artificial lighting, shortening the period of darkness by providing night-interruption (NI) lighting, or using cyclic or intermittent lighting during which incandescent lamps are turned on and off at specific intervals for a certain duration.

Matthew G. Blanchard and Erik S. Runkle from the Department of Horticulture at Michigan State designed an experiment to evaluate a technology for long-day lighting for commercial production of ornamentals. The experiment used four popular flowering ornamentals (campanula, coreopsis, petunia, and rudbeckia) to compare the efficacy of a rotating high-pressure sodium lamp (HPS) in promoting flowering with night-interruption lighting using incandescent lamps.

Seedlings were grown under natural short-day photoperiods (12 hours or less) and night-interruption treatments were delivered from a rotating HPS lamp mounted at one gable end of the greenhouse or from incandescent lamps that were illuminated continuously for four hours or cyclically for 6 minutes every 30 minutes for 4 hours. Within 16 weeks, 80% or more of the plants of each species that received night-interruption lighting had a visible flower bud or inflorescence; all species but petunia remained vegetative under the short-day treatment. Flowering of all species grown at 13 meters from the rotating HPS lamp was delayed by 14 to 31 days compared with those under continuous incandescent illumination.

The researchers estimated that the weekly cost to operate night-interruption lighting was an impressive 80% to 83% less than the cost of continuous incandescent lighting. According to Blanchard and Runkle, "a rotating HPS lamp operated continuously during a 4-hour night-interruption was effective at promoting flowering in these long-day species and consumed less energy compared with incandescent lamps operated continuously." The researchers concluded that use of rotating high-pressure sodium lamps could be effective in commercial production as long as the light intensity is above the recommended value.

The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/cgi/content/abstract/45/2/236

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

Michael W. Neff | EurekAlert!
Further information:
http://www.ashs.org

More articles from Agricultural and Forestry Science:

nachricht Researchers discover a new link to fight billion-dollar threat to soybean production
14.02.2017 | University of Missouri-Columbia

nachricht Important to maintain a diversity of habitats in the sea
14.02.2017 | University of Gothenburg

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>