Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: Christina Stadler
Starfsvettvangur / Affiliations: Agricultural University of Iceland
Kynnir / Presenter: Christina Stadler
Growers in Iceland have adopted intensive use of supplementary lighting to maintain year-round production. Lighting methods with high-pressure vapour sodium lamps (HPS) and light emitting diodes (LED) are quested that increase yield and profit margin.
In the research greenhouse of the Agricultural University of Iceland were tomatoes grown from November 2020 to the middle of March 2021. Transplants received either HPS lights or LEDs and in continuous production were different LED treatments (top lighting with HPS and LED lights and without (Hybrid) or with LED interlighting (Hybrid+LED) tested.
Plants that received LEDs in young plant production were about half a week earlier ripe than plants that received HPS lights. This might be caused by the higher leaf temperature of plants that received LEDs. However, at the end of the harvest period was total yield, marketable yield and their number independent of the light treatment. When considering the marketable yield per cluster, treatments that received LEDs in young plant production had a lower value than plants that received HPS lights in young plant production.
“Hybrid+LED” used about 21% less energy than “Hybrid”. Light related costs were higher for “Hybrid” than “Hybrid+LED”. Used kWh’s were better transferred into yield with “Hybrid+LED” than with “Hybrid”.
It can be advised to grow high wire transplants under HPS lights. However, after transplanting a Hybrid system where LEDs are used as top lighting seems to be recommended