|
|
Authors: | S. Torre, A.G. Roro, S. Bengtsson, L.M. Mortensen, K.A. Solhaug, H.R. Gislerød , J.E. Olsen |
Keywords: | morphology, temperature, shoot elongation, UV-B |
DOI: | 10.17660/ActaHortic.2012.956.22 |
Abstract:
Chemical plant growth retardants (PGRs) are used to control height of greenhouse grown plants.
Increasing environmental awareness has strongly promoted interest in alternative methods.
Since UV-B is known to reduce shoot elongation, the use of supplemental UV-B radiation or UV-B and UV-A-transmitting cladding material such as F-clean appears highly interesting.
Substantially reduced shoot elongation was observed in a variety of bedding and pot plants produced in the spring in Norway at 59°N under F-clean compared to polyethylene.
Furthermore, although natural UV levels are low in the autumn at 59°N, a 30% reduction in the use of PGRs as a consequence of reduced shoot elongation was then observed in poinsettia (Euphorbia pulcherrima) under F-clean.
Poinsettia exposed to short diurnal periods of UV-B radiation in the night, also showed reduced internode lengths and increased branching.
Effect of UV-B and its interaction with temperature on morphology was investigated using pea (Pisum sativum) as a model system.
The UV-B stimulated reduction in shoot elongation was substantially enhanced when given in combination with a temperature drop treatment.
Also, plants were then less susceptible to UV-B-induced damage, indicating an effect of temperature reduction on UV-protective mechanisms.
|
Download Adobe Acrobat Reader (free software to read PDF files) |
|