An investigation of pea and cereal varieties for organic intercropping in Sweden

Sammanfattning: Organic farming, intercropping and the conservation of landraces are agroecological methods of transitioning to a more sustainable and resilient agricultural system, however there is a lack of data on varieties suitable for organic intercropping. Therefore, two spatially parallel field trials were conducted with 11 pea varieties intercropped with oat, and 38 varieties of cereals (wheat, oat, and barley), in sole crops. The trials were conducted at the Swedish University of Agricultural Sciences (SLU), Alnarp, in the south of Sweden. Length and maturity times of the intercropping trials were measured and analysed at regular time intervals for around 15 weeks, for the cereals the same was done with height and maturity times. Grain yield was also recorded for the cereal trial. This was done to assist variety selections for an upcoming intercropping trial that will be conducted at a similar location in the years 2025-2026. The results showed a variation in height, length, and maturity times across the varieties, which in many cases overlapped or were similar to each other, offering a possibility to select combinations for further trials. The cereal yield differed between varieties, with Gutekorn (an old variety that had completely lodged by harvest) yielding the lowest at 1250kg per hectare and Esperanza and Saludo (modern organic varieties) yielding the highest at 4000kg per hectare. The results are discussed with reference to agroecological knowledge and development, with emphasis on the importance of farmer participation when selecting and developing varieties for organic intercropping systems. In conclusion, the varieties collection of both peas and cereals included a range of diversity for the assessed traits, offering opportunities for selecting good material for further organic intercropping trials.