Michel Verheul
Senior Research Scientist
(+47) 934 08 525
michel.verheul@nibio.no
Place
Særheim
Visiting address
Postvegen 213, NO-4353 Klepp stasjon
Authors
Michel VerheulAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
To document effects of High-Pressure-Sodium (HPS) and Light-Emitting Diodes (LED) lamps, six different cucumber cultivars (‘DeeRect’, ‘HiLight’, ‘Imea’, ‘Keirin’, ‘Shakira’ and ‘Topvision’) were grown hydroponically in a semi-commercial greenhouse compartment using standard HPS or LED supplemental top-light from December to March. A PPFD of 240 µmol m-2s-1, 20h a day, was used for both lamp types. In addition, plants were grown with or without LED inter-lighting (45 µmol m-2s-1, 20h a day). Global radiation during the experiment was less than 1.5 MJ m-2day-1. Setpoints for day and night temperatures were 24 and 21 oC respectively. CO2 concentration in the greenhouse was kept at 1100 ppm. Morphological traits (stem length, leaf area, leaf thickness, dry weights), yield (fruit fresh weight and number of fruits) as well as quality parameters were registered. Results show that the use of LED top-light reduced yield considerably compared to HPS top-light, mainly due to a reduction in the number of 1st class fruits harvested. Plants grown using HPS top-light were longer, had more internodes, a higher fruit weight, bigger leaf area and leaf area index (LAI) and ‘thinner’ leaves compared to plants grown using LED top-light. Light use efficiency (g FW mol PAR-1) was highest using HPS or a combination of HPS and LED inter-light and lowest using LED combined with LED inter-lighting, especially at the start of the harvesting period. Huge differences in yield reduction between different cultivars were observed. LED top light reduced the yield of ‘DeeRect’ with 35% and of ‘HiLight’ with 5% compared to HPS top light. Little differences in quality traits were observed between cultivars grown under HPS or LED lamps. However, inter lighting increased fruit weight and fruit quality (color, dry matter content, soluble solid content, chlorophyll content, vitamin C content and storage properties). Causes of differences between lamp types and effects on commercial greenhouse cucumber production in Norway are discussed.
Authors
Michel VerheulAbstract
No abstract has been registered
Intelligent use of light and new lighting technology for energy efficient and quality-assured year-round production of cucumber in Norway