Research matters... long-day lighting to promote growth

Dr Ken Cockshull, Emeritus Fellow at Warwick HRI, highlights the latest findings from horticultural research.

Some plants grow faster when given low-intensity long-day lighting and various reasons have been given for this. The experiments described here were aimed at establishing why plants grow faster and what features their responses have in common.

Petunia, Impatiens and tomato seedlings were grown in daylight for eight hours each day and in light-tight compartments for 16 hours.

The daylight was extended for either four or eight hours using light from a combination of tungsten and fluorescent lamps.

A night-interruption treatment was also given, using tungsten lamps for two hours around midnight.

Growth of all three species was promoted by all treatments, especially when natural light levels were low. Some of the extra growth of Petunia was probably attributable to its upright habit and larger leaves in long days. Long days produced no differences in leaf thickness in tomato and although the long-day leaves were a darker green, their photosynthesis was not promoted.

Impatiens showed no change in either leaf thickness or greenness in long days. It is suggested that the extra hours of low-intensity light generated enough photosynthesis to offset some respiration and hence promote growth in all three species.

If correct, long-day lighting should promote growth in most plants.

Why Does Low-intensity, Long-day Lighting Promote Growth in Petunia, Impatiens and Tomato? by Adams, Valdes and Langton (2008). Journal of Horticultural Science & Biotechnology 83 (5): 609-615.

The authors' abstract of their manuscript can be seen in full at www.jhortscib.com.


Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Sign up now
Already registered?
Sign in

Before commenting please read our rules for commenting on articles.

If you see a comment you find offensive, you can flag it as inappropriate. In the top right-hand corner of an individual comment, you will see 'flag as inappropriate'. Clicking this prompts us to review the comment. For further information see our rules for commenting on articles.

comments powered by Disqus

Read These Next

Is a post-Brexit seasonal worker scheme now impossible?

Is a post-Brexit seasonal worker scheme now impossible?

The UK fresh-produce sector has reacted with dismay at the latest developments in the ongoing debate, largely conducted out of public view, on whether UK horticulture will still have access to seasonal migrant workers when the UK leaves the EU in 18 months' time.

Can UK fresh produce come out of Brexit ahead?

Can UK fresh produce come out of Brexit ahead?

UK production horticulture can become more profitable under one possible Brexit scenario, while other more drastic scenarios will lead to only minor losses in profitability, a new report argues.

Business Planning - Staff are your greatest asset

Business Planning - Staff are your greatest asset

An effective strategy to retain staff is the best way for any business to avoid a potential recruitment crisis, Neville Stein advises.


Follow us on:
  • Facebook
  • LinkedIn
  • Twitter
  • Google +
Horticulture Jobs
More Horticulture Jobs

Pest & Disease Tracker bulletin 

The latest pest and disease alerts, how to treat them, plus EAMU updates, sent direct to your inbox.

Sign up here

Professor Geoffrey Dixon

GreenGene International chair Geoff Dixon on the business of fresh produce production
 

Read Professor Geoffrey Dixon