Optimizing lentil-based mixed cropping with different companion crops and plant densities in terms of crop yield and weed control

Abstract

Mixed cropping of lentil (Lens culinaris) with five spring-sown companion crops: naked barley (Hordeum vulgare), wheat (Triticum aestivum), oats (Avena sativa), linseed (Linum usitatissimum) and buckwheat (Fagopyrum esculentum) was compared with monocropping at the organic research station Kleinhohenheim, University of Hohenheim, Germany, in 2009 and 2010. Besides sole lentil and sole companion crops, three mixing ratios (3:1, 1:1 and 1:3) were used. The aim of the study was to identify the most suitable companion crop and mixing ratio for lentils in terms of yield, weed infestation and lodging under temperate climatic conditions. Lentils yielded 1.47 t ha−1 in monocropping and 0.58–1.07 t ha−1 in mixed cropping, depending on the mixing ratio and companion crop. The land equivalent ratio (LER) was higher in mixed cropping than monocropping generally. Lentil–wheat and lentil–barley mixed cropping with a ratio of 3:1 resulted in the highest LER (ca. 1.50); lentil–linseed had the lowest LER for all ratios. Least lodging was observed in lentil–wheat and lentil–oat mixed cropping. Compared with lentil monocropping, mixed cropping with ratios of 3:1, 1:1 and 1:3 (lentil/companion/crop) reduced weed biomass by 29, 41 and 24 %, respectively. Mixed cropping with wheat and barley for lentil in central Europe gives marked benefits in terms of grain yield, weed control and crop lodging resistance. Lentil production in organic farming systems is well suited to mixed cropping approaches.