[N-fertilizing to cauliflower, swede and onion: Effect on yield level and on the quantity of nitrogen in plant residues and in the soil in autumn and in spring]

abonos nitrogenados allium cepa application date application rates azote brassica napobrassica brassica oleracea botrytis chemical composition composition chimique date d'application dose d'application fertilisation fertilizer application feuille hojas leaves nitrogen nitrogen fertilizers noruega norway racine rendement rendimiento residues residuos roots soil sol stems suelo tallo tige yields