缺氮中药材如缺氮,植株基部老叶会黄化、脱落,植株呈淡绿至黄绿,叶片变小,植株新梢的延长严重受阻,同时还出现早衰。防治措施:每667平方米可追施尿素15～20千克,还可进行叶面追补,叶面喷施1%～3%的尿素稀释液。缺磷中药材如缺磷,植株深绿,叶柄呈紫红色,叶片变薄、变小,植株矮小 Nitrogen deficiency Chinese herbal medicines such as nitrogen deficiency, the old leaves of the plant will yellow, fall off, plants pale green to yellow-green, leaves smaller, plant new shoots extended severely obstructed, but also premature aging. Control measures: Each 667 square meters of urea can be topdressing 15 to 20 kg, but also for leaf foliage, foliar application of 1% to 3% urea dilution. Phosphorus deficiency Chinese herbal medicines such as phosphorus deficiency, dark green plants, petiole was purple, leaves thinning, smaller, short plants