Rye grass as a catch crop in spring barley

absorption de substances nutritives azote calidad catch cropping choix de la date crop yield cultivo intermedio cultivos de primavera culture de printemps danemark denmark dinamarca ensemencement essai fertilisation fertilizer application grain granos hordeum vulgare lolium multiflorum lolium perenne nitrate nitrates nitratos nitrogen nitrogen content nutrient uptake paille paja pruebas quality rendement des cultures rendimiento de cultivos siembra soil types sowing spring crops straw teneur en azote timing trials type de sol