烟草也和其它作物一样,需要各种营养元素供应才能正常生长发育。一旦营养元素供应失调,就会出现各种异常症状。常见的有以下几种: 缺氮:早期症状为叶色浅淡,生长缓慢或停止生长。下部老叶变为黑褐色或拈黄色,逐渐干枯脱落。其它叶片向上直立与茎夹角较小。如果口肥未施氮素化肥,可在培土时每亩施15—20公斤三元复合肥,已施过口肥,则应视情况减少追肥量,以免影响烟叶品质。缺磷:往往出现在幼苗移栽后第一个月,表现生长缓慢,植株矮小,叶色暗绿微紫,叶形窄长而上翘,下部叶片出现小白斑点。烘烤期叶片烤后呈深棕 Like other crops, tobacco also needs a variety of nutrients to grow normally. Once the supply of nutrients imbalance, there will be a variety of abnormal symptoms. Common are the following: Nitrogen deficiency: early symptoms of pale leaves, slow growth or stop growing. The lower part of the old leaves turn dark brown or twist yellow, gradually dry off. Other leaves upright and stem angle smaller. If the fertilizer does not apply nitrogen fertilizer, soil fertilization in 15-20 kg per acre Shi compound fertilizer, fertilizer has been applied, it should reduce the amount of fat dressing, so as not to affect the quality of tobacco. Phosphorus deficiency: often occurs in the first month after transplanting seedlings, the performance of slow growth, plant dwarf, dark green leaves purple, narrow and long leaf shape upturned, the lower leaves appear white spots. Baking leaves roasted dark brown