Quality improvement and steady production techniques of continuously cropped soybeans [Glycine max], 3: Investigation of soybean cultivation applied sigmoidal releasing-types of coated urea fertilizer

abonos fosfatados agronomic characters calidad continuous cropping cultivation cultivo cultivo continuo culture continue engrais organique gestion du sol glycine max manejo del suelo mejora de suelos organic fertilizers phosphate fertilizers pratique culturale quality soil improvement soil management soil types tipos de suelos type de sol