试验研究不同施氮水平下不同成熟度的烤烟叶片光谱红边参数特性,采用相关分析和逐步回归方法确定红边位置为烟叶成熟度的特征变量。通过分析红边位置与成熟叶片和过熟叶片的关系,找到适熟叶片的红边位置变化范围,同时采用回归模型用红边位置反演得出相应的叶绿素含量,对采用红边位置估测成熟度的准确性进行检测。结果表明：运用红边位置估测叶绿素含量效果较好,从而可以判断烟叶成熟度,并且得出成熟叶片红边位置为693—695nm,过熟叶片红边位置极值为688nm。因此,本研究为采用光谱技术测定烤烟叶片成熟度确定了理论依据,并可为解决烟草生产中成熟采收问题提供参考。

The expermi ent was conducted to investigate the relationships amongst the leaf red edge characteristics and physiological and biochemical matters in tobacco lea,f especially pigment contents, in differentmature stages. The tobaccoswere grown under three levels ofnitrogen supply during the period of May 2005 to September 2005. The regression analysis showed there was a significant correlation between the red edge position and chlorophyll a+b contents in tobacco. The results indicated that the red edge positionwithin\nthe range of693—695nm was able to be used as a good reflection of ripe leaves, and the red edge position of 688nm was confirmed as the character of best overripe. Leafmaturity could be identified through chlorophyll\na+b contents estmi ated by the corresponding red edge positions. Accordingly, this study suggests that the spectral data serve aspromisingmeasures to predictthematurity leveloftobacco lea,f and also provides a strong\nsupport for decisionmaking of tobacco production.