The effect of cover crop on undersown grasses for seed production: Experimental studies [including 4 manuscripts and 1 conference paper]

brassica napus cover plants crop yield cultivo intercalado culture intercalaire dactylis glomerata danemark denmark densidad density dinamarca festuca pratensis festuca rubra field experimentation hordeum vulgare intercropping lolium perenne pisum sativum plantas de cobertura plante de couverture poa pratensis production de semences rendement des cultures rendimiento de cultivos seed production triticum aestivum vicia faba