Pakistan: Fertilizers trials in farmer's fields on mexi-pak 65 wheat, winter, rabi 1969-70, Southern region and Western Region

abonos abonos potasicos application rates azote cost benefit analysis dose d'application engrais engrais potassique fertilizers fosforo ganancias nitrogen phosphore phosphorus plant response potash fertilizers profit rendement rendimiento respuesta de la planta trial methods trigo wheats yields