苹果树缺肥的症状缺氮：氮素是叶绿素的重要成分。缺少氮素，叶色变淡发黄，叶片小而薄，容易早期脱落。枝条细弱，叶芽干瘦，花芽少且不饱满。结果少而小，品质差。植株生长不良，严重缺氮亦可造成全株死亡。缺磷：在氮足磷少的情况下，直接影响脂类物质的形成和输导光合... Nitrogen deficiency: nitrogen is an important component of chlorophyll. Lack of nitrogen, leaf color pale yellow, small and thin leaves, easy to fall off early. Slender branches, leaf buds thin, flower buds less and not full. The results of small and small, poor quality. Poor plant growth, severe nitrogen deficiency can also cause death of the whole plant. Phosphorus deficiency: in the case of nitrogen enough phosphorus, a direct impact on the formation of lipid and transport photosynthesis ...