南雄烟区主栽烤烟品种成熟期丙二醛含量变化规律研究

Changing Rule of MDA Content in Main Flue-cured Tobacco Varieties at Mature Stage in Nanxiong

通过对南雄烟区不同烤烟品种成熟过程中活体、离体烟叶丙二醛含量及其变化规律分析,揭示不同烤烟品种烟叶的成熟度与丙二醛含量及其变化的规律相关性差异。结果表明:(1)大田状态下,上部烟叶,‘K326’丙二醛含量随时间呈"S"型变化,‘粤烟97’、‘粤烟98’丙二醛含量随时间呈类指数型变化,采收时MDA含量分别为21.35、18.75、20.59μmol/g;中部叶,3个烤烟品种均呈类指数型变化,采收时烟叶MDA含量为19.74、12.55、12.98μmol/g。(2)离体状态下,上部烟叶,‘K326’丙二醛含量随时间呈类指数型变化,‘粤烟97’和‘粤烟98’呈"S"型变化;中部烟叶,3个烤烟品种均呈"S"型变化。(3)离体烟叶MDA含量在短时间内达到大田状态下成熟采收时的含量水平,而离体后上、中部烟叶MDA含量均呈现"S"型变化趋势,当达到采收值时正好处于离体烟叶"S"型变化趋势的拐点,即离体烟叶MDA含量变化到达拐点之前与大田状态下MDA含量的变化趋势一致。研究表明不同烤烟品种在烤烟成熟过程中丙二醛含量及其变化规律可以指示其成熟度。

According to the analysis of MDA content and its variation in leaves of different flue-cured tobacco varieties in Nanxiong, the correlation difference between the maturity of tobacco leaves and the content of MDA was revealed. The results showed that： （1） under field condition, the MDA content in upper leaves of ＇K326＇ showed ＇S＇ type change with time variation, and that of ＇Yueyan97＇ and ＇Yueyan98＇ showed exponential change with time variation, the content of MDA of the three varieties was 21.35, 18.75 and 20.59 μmol/g at harvest time, respectively; the MDA content of middle leaves in three flue-cured tobacco varieties all showed the same exponential change, and the MDA content was 19.74, 12.55, 12.98 μmol/g at harvest time, respectively; （2） in vitro, the MDA content in upper leaves of ＇K326＇ showed exponential change with time variation, and ＇Yueyan97＇ and ＇Yueyan98＇ showed ＇S＇ type change; the MDA content of middle leaves in the three flue-cured tobacco varieties showed ＇S＇ type change; the vitro MDA content reached the level ofharvest in a short period of time, and the content of MDA in the upper and middle leaves all showed ＇ S＇ type change, when the harvest value was reached, it was just the turning point of the ＇S＇ type, which meant the change of vitro MDA content in tobacco leaves was consistent with the change of MDA content in vivo before the inflection point. The results showed that the content of MDA and its changing rule could be used to indicate the maturity （ripe, mature and over matured） of different flue-cured tobacco varieties.