Sweden: Greenhouse oilseed rape grower now uses hybrid LED, HPS lights
Oilseed rape is a very important crop and valued for its oil for food and fuel. The development of new oilseed rape varieties is driven by higher productivity demands and also by more specialized end products for example for biofuels production.
Using HPS as supplementary lighting grows weak plants with too long hypocotyls (left) whereas combining Valoya LEDs with HPS improved plants significantly to compact and strong plants (right)
In the breeding process of new oilseed rape varieties, the young plants are cultivated, typically during the winter in greenhouses using supplementary lighting to improve or enable growth. Traditionally, HPS lamps have been used for the illumination. Plant quality has deteriorated during winter months due to the poor quality of the HPS light spectrum to plants. The poor quality of the oilseed rape plants appears as elongated hypocotyls. Elongated hypocotyls make transplantation of the plants into the field more difficult, causing damage to the plants and thus, compromising their survival through the breeding program. The plants should be compact, strong and have short hypocotyls. Plant quality can be partly improved by lowering greenhouse temperature, but this leads to a longer production time.
Lantmännen SW Seed has been working with Valoya lights both in Sweden and in Germany. The Lantmännen SW Seed team in Germany tested the effect of different light sources to improve the quality of the oilseed rape seedlings. They found that the use of Valoya LEDs together with the existing HPS lamps in the trial greenhouse improved plant quality to a level similar to the high quality of plants grown outdoors during the summer, i.e. strong, compact and with very short hypocotyls. Light intensity is not different compared with HPS alone and when both lamps are combined, therefore the positive growth effect is due to the spectrum of the Valoya LED lights.
Improving the quality of plants, without slowing down the production time is very valuable for seed companies, as development programs for new plant varieties are costly and can take up to 10 - 12 years. Each plant in the breeding program receives significant care and analysis during this time, which leads to a high cost. Thus, a strong plant equals high survival rates and thus, protection of the investment in it.
The oilseed rape seeds were sown on December 10th, 2012 and grown until January 7th, 2013 in the greenhouse at the temperature of 10 °C. When they matured to “6 leaf stage”, they were placed into vernalization at 2-3 °C for a minimum of 6 weeks at low light intensity. The plants were then transplanted to the field in early March 2013.
For more information:
Valoya
Lars Aikala
+538 40 546 6639
www.valoya.com
