Effects of thin manure upon the quality of sugar beets on the basis of foreign investigations [liquid manures]

abonos agricultural chemicals amendement du sol calidad crops cultivos economic plants engrais engrais organique enmiendas del suelo fertilizers industrial crops liquid manures plantas plantas azucareras plantas industriales plante plante de culture plante industrielle plante racine plants produit agrochimique purin quality remolacha azucarera root crops soil amendments sugar beet sugar crops