共 3 条
[2]
Soil testing and plant analysis .2 Geraldson C M J. Soil Sci Soc Amer.Inc . 1990
[3]
S tem n itrate n itrogen and y ield ofw heat in a perm anen t rotation experim en t .2 Papasty lianou I,Puckridge D W. A ust J A gric R es . 1983