esponse of two alfalfa varieties to phosphorus, P and potassium, K fertilization under newly reclaimed sandy soil at Middle Egypt

abonos fosfatados abonos potasicos egipto egypt engrais phosphaté engrais potassique medicago sativa phosphate fertilizers potash fertilizers reclaimed land rendement rendimiento sandy soils sol sableux suelo arenoso terre récupérée tierras rehabilitadas variedades varieties variété yields égypte