Weed suppression and yield of sole and intercropped grain legumes under the conditions of organic farming
In low input systems, grain legumes are essential for protein-rich fodder but also for a nitrogen supply in crop rotation. However, grain legume production can be challenging due to low yields and slow early development causing levels of high weed infestation. A field trial was conducted in 2018 and 2019 at the Thünen Institute of Organic Farming in northern Germany. Two cultivars of the grain legumes faba bean, pea, blue lupin and white lupin were tested alone and intercropped with wheat. Intercropped faba bean and pea had a better shading of the crop canopy in the critical growth phase of stem elongation. Thus, the weed biomass in intercropped plots was lower than in the respective sole crops. The average total yields were highly influenced by year or year × cropping system. Nevertheless, the average total yields (RYT= 0.98−1.26) of intercropped legumes were higher than the yield of sole cropped legumes.