烟草和其他植物一样,需要各种元素才能正常生长发育。当营养元素供应失调时,会出现各种异常症状。缺氮最早的症状是叶色浅淡,生长缓慢或停止,下部的老叶变成柠檬或橙黄色,并逐渐地干枯脱落。其余叶片向上直立,与茎的角度变小。烟株产量是随施氮量的增加而提高,而烟草的品质则随施氮量的增加而下 Like other plants, tobacco requires various elements for normal growth and development. When the nutrient supply disorders, there will be a variety of abnormal symptoms. The earliest symptoms of nitrogen deficiency is pale leaves, slow growth or stop, the lower part of the old leaves into lemon or orange, and gradually dry off. The remaining leaves upright, and the angle of the stem becomes smaller. The yield of tobacco plants increased with the increase of nitrogen application, while the quality of tobacco decreased with the increase of nitrogen application rate