The effect of N and P fertilization on winter survival of winter wheat under zero-tilled and conventionally tilled management

cero-labranza cold cultivation cultivo date fertilizantes fosfatados fertilizantes nitrogenados fosforo frio froid hiver hivernage invierno losses nitrogen fertilizers overwintering perte phosphate fertilizers phosphore phosphorus pratique culturale resistencia a la temperatura temperature resistance timing trigo triticum wheats winter zero tillage