What are the optimal legume species, genotypes, and fertilization strategies for plant-based foods?

Summary

Purposes and aims: The transition towards more sustainable and plant-based diets is steadily increasing the demand for climate-friendly and high-quality crops. Legumes have a great potential as raw materials and ingredients for human consumption, but in Northern Europe, they are underutilized food crops. This is mainly due to a historical focus on legumes for feed and import of soybeans, which are unsuitable for most Northern European climates. The aim of the study was therefore to identify legume species, genotypes and management strategies suitable for production in Denmark. It was hypothesized that especially faba beans (Vicia faba) and peas (Pisum sativum) are suitable candidates and that fertilization strategies can be optimized to improve their growth, harvest yield and quality. Methods: Field trial and greenhouse studies were conducted to explore 10 commercially available faba bean and pea genotypes as well as >350 gene bank accessions of peas in the Danish research projects AQRIFood and Peas & Love, respectively. Plants were grown according to organic regulations and their growth, harvest yield and seed quality at maturity were evaluated. For the commercial genotypes, protein concentrates and isolates were also produced and analysed. For selected genotypes and accessions, fertilization trials were conducted to optimize symbiotic nitrogen fixation, legume growth, harvest yield and seed quality. Results: For the commercially available faba bean and pea genotypes, all showed great agronomic potential and only minor differences in protein and nutrient contents of raw materials, concentrates and isolates. However, significant differences were found for selected anti-nutrients such as vicine and convicine in faba beans. For the gene bank accessions of peas significantly greater variations in protein and nutrient contents were found. However, the harvest yields also varied more than for the commercial genotypes. Finally, it was shown that fertilization with sulphur could improve pea growth, harvest yield and seed quality. Conclusions: It is concluded that faba beans and peas are highly suitable legume species as raw materials and ingredients for plant-based foods. However, genotypic differences and fertilization strategies must be further explored to increase the utilization of legumes for human consumption in Northern Europe.