The diphenylamine method could indicate the nitrogen status in plant which changed with the different rate of nitrogen fertilizer application. it is more suitable to be used in the practice.

• 而二苯胺法测定结果可以反映作物体内硝态氮含量随施肥量变化情况，并且由于其快速、简便的特性，更适于在生产中推广应用。