缺氮症状是植株瘦弱,枝蔓细,叶呈黄绿色并发黄,褪绿时先从老叶开端,逐步向上扩展,甚至新梢下部叶片脱落,落花落果,果粒小,新梢伸长生长停滞早。防治方法:叶片喷洒浓度为o.2%加.3%的尿素2~3次,每7~10天喷一次,见效快,并联结浇水,泥土中再施尿素。缺磷症状是植株生长迟缓,叶片小,叶色初为暗绿,逐步失去光泽,最后变为青铜色,严重缺磷肘叶片呈暗紫色,老叶首先表现症状。叶片变厚、变脆,发生早期落叶,产量低,品质差。 Nitrogen deficiency is a thin plant, branches and thin, yellow and green leaves and yellow, chlorosis, the beginning of the old leaves from the beginning, and gradually expand upward, and even the lower part of shoots off, drop flowers, fruit small, shoot growth Stagnation early. Prevention and treatment methods: leaf spray concentration of o.2% plus .3% of urea 2 to 3 times, spray every 7 to 10 days, quick, and join the water, soil re-urea. Phosphorus deficiency symptoms are plant growth retardation, small leaves, leaf color early dark green, and gradually lose their luster, and finally become bronze, phosphorus deficiency elbow leaves were dark purple, the first symptoms of old leaves. Leaf thickening, brittle, early deciduous, low yield, poor quality.