大棚蔬菜缺肥诊断法大棚蔬菜需肥量较大，若肥源不足，就会在植株上表现各种病症。缺乏氮肥：其初显现部位主要在叶片上，即叶子呈淡绿色或黄色，茎杆不久也发生同样的变化，这种现象通常是从老叶片开始，最后整个植株变成淡黄色或褐色。缺乏磷肥：缺磷的症状多见于生长初... Greenhouse vegetables lack of fertilizer diagnosis method Greenhouse vegetables need more fertilizer, if the lack of fertilizer, it will show a variety of plant diseases. Lack of nitrogenous fertilizer: the initial appearance of the site is mainly on the leaves, that is, the leaves are light green or yellow, and the same changes occur soon in the stems. This phenomenon is usually started from the old leaves, and finally the entire plant becomes pale yellow or brown. Lack of phosphate fertilizer: phosphorus deficiency symptoms more common in early growth ...