(一)缺氮:油菜缺氮长势差,新叶生长慢,叶小色淡、绿中带黄,植株矮小,主茎叶片少,冬前春后单株绿叶少,后期有效分枝少荚少粒少而导致减产。对于这类油菜田,结合中耕每亩用碳铵20—25公斤加人粪尿10担兑水浇施。(二)缺磷:油菜缺磷根系小,叶片小出叶慢,叶肉变厚而叶片灰暗无光 (I) Nitrogen deficiency: The growth of nitrogen deficiency in rape is poor, the growth of new leaves is slow, the leaves are pale, the green is yellow, the plants are short, the main stems are few, Less pods and less lead to reduced production. For such rape fields, with the cultivation of ammonium bicarbonate per acre 20-25 kg plus manure 10 bears against the water facilities. (B) lack of phosphorus: phosphorus-deficient roots of rape, leaves a small leaf slowly, thicken leaves and dark leaves without light