It was pointed out that the medium N application level and low tempera ture yellowing or high moisture ounng condition was good for the quality of tobacco leaf.

• 低温或高湿变黄使各种酶在较长时间内维持活性状态，使物质转化和积累更充分，有利于烟叶香味特征的形成，烤后烟叶品质较好。