Sustainable strawberry production in high plastic tunnels

BærKraft focuses on strawberry, the most important fruit- and berry crop in Norway. There has been a 45% increase of fruit and berry consumption in Norway over the recent five years, and it is estimated that this will continue to grow with another 50% over the next decade. The growing market demands have thus far been covered by imports, but the Norwegian fruit- and berry industry is now developing ample strategies to increase the domestic market share. To ensure stable high yields of optimal quality of strawberry, a top priority is to stimulate to a higher proportion of domestic production in high plastic tunnels. This will enable a much better control of climatic and growing conditions compared to open-field production. The project have had a special focus on increasing production in the early and late parts of the growing season. Growers involved in the project have experience from both conventional and organic production, and results from BærKraft will contribute to a higher share of organically produced strawberry. In dialogue with the industry, the following work have been prioritized: i) Environmental responses in new cultivars, especially among everbearers to possibly enable longer cropping seasons than with the traditional single-cropping types; ii) nutrient supply and watering in soil and non-peat substrates; iii) ultraviolet light against grey mould in fruit, and warm steam against grey mould and powdery mildew in strawberry transplants; and iv) a technical and economical basis for strawberry production in high plastic tunnels. The project is constituted of a group of scientists, advisors and growers with a long tradition for research based industrial development, and with a strong publication record among the involved scientists. BærKraft have included MSc and PhD students and highly recognized international research groups in different project tasks, ensuring recruitment to the industry and research, and success of the project. A PhD student has conducted experiments with everbearing (remontant) strawberry cultivars in tunnels and in controlled environment (phytotron). Work has been conducted on fertigation- and irrigation strategies on strawberry grown in trays in different mixes of substrate. Growing in wood fiber from Norwegian spruce seems particularly interesting and promising. Laboratory and field trials have shown that UV may reduce grey mould in strawberry, but the dose needed is higher than what is necessary to control powdery mildew, and this may make it difficult to combine with an integrated pest management strategy using beneficial's against mites and insect. Powdery mildew was eradicated after 2 hours with warm steam treatments in the Plant Sauna at 40°C. Grey mould was strongly reduced after 4 hours at 44°C, while strawberry mite was completely eradicated with the same treatment. However, warm steam treatments at 44°C for 4 hours did not reduce the population of two-spotted spider mite to much extent. Five strawberry cultivars (both long-day and short-day cultivars) were not negatively affected by treatments in the PlantSauna at 44°C for 2 or 4 hours. Dissemination activity has been high in the project, with field visits, also including international collaborators (Proefcentrum Hoogstraten, Belgium), discussion groups and presentations at national and international meetings.

Har økt arealet i plasttunneler og gitt jordbær i en lengre sesong. Kunnskap om planteoppal av nye sorter kan medføre ny virksomhet. Vekstmedier basert på trefiber fra gran er utviklet. Hunton Fiber AS har lansert Fibergrow®, og NORGRO to nye blandinger med Fibergrow® og torv. Produktene vil videreutvikles. Ny kunnskap om bekjemping av sopp med ultrafiolett (UV) lys er brukt til utvikling av en UV-robot. Et konsept for behandling av planter med vanndamp (Plantesauna) er utviklet. Plantsauna AS er etablert og har startet kommersiell produksjon. UV og Plantesauna medfører redusert bruk av plantevernmidler. NLR og dyrkere har utarbeidet økonomiske kalkyleverktøy som vil videreutvikles til andre bærproduksjoner. Rutiner for dyrkingstiltak i produksjonen i samarbeid dyrker-rådgiver-forsker er utviklet. Samhandling vil optimalisere jordbærproduksjonen videre. Har involvert studenter, og et aktivt samarbeid med internasjonale partnere. Vil føre til rekruttering og nye samarbeidsprosjekt.

BærKraft focuses on strawberry, the most important fruit- and berry crop in Norway, but derived knowledge may be transferred to other crops. There has been a 45% increase of fruit and berry consumption in Norway over the recent five years, and it is estimated that this will continue to grow with another 50% over the next decade. The growing market demands have thus far been covered by imports, but the Norwegian fruit industry is now developing ample strategies to increase the domestic market share. To ensure stable high yields of optimal quality of strawberry, a top priority is to stimulate to a higher proportion of domestic production in high plastic tunnels. This will enable a much better control of climatic and growing conditions compared to open-field production. The project has a special focus on increasing production in the early and late parts of the growing season. Growers involved in the project have experience from both conventional and organic production, and results from BærKraft may contribute to a higher share of organically produced strawberry. In dialogue with the industry, the following R&D work is prioritized: i) Environmental responses in new cultivars, especially among everbearers to possibly enable longer cropping seasons than with the traditional single-cropping types; ii) nutrient supply and watering in soil and non-peat substrates; iii) ultraviolet light against grey mould in fruit, and hot steam against grey mould and powdery mildew in transplants; and iv) a technical and economical basis for strawberry production in high plastic tunnels. The project is constituted of a group of scientists, advisors and growers with a long tradition for research based industrial development, and with a strong publication record among the involved scientists. BærKraft will include MSc and PhD students and a highly recognized international research groups in different project tasks, ensuring recruitment to the industry and research, and success of the projet.