湘西不同地理区域烟叶的理化特性

Physicochemical characteristics of tobacco leaves in different geographic regions of Xiangxi

以湘西不同地域（桑植县、凤凰县、靖州县）和桑植县不同海拔烟区的中部烟叶为材料，对烟叶的理化特性进行了分析。结果表明：湘西不同地域烟区烟叶的叶宽、含水率和叶片厚度均差异显著，桑植县炯区烟叶叶宽（26．52cm）和含水率（18．98％）最高，而靖州县烟区烟叶叶片厚度（96．67μm）最高；湘西不同地域炯区烟叶的钾、氯、总糖、类胡萝卜素和芸香苷含量、两糖差、钾氯比的差异较大，总糖含量随纬度降低而增加，类胡萝卜素和芸香苷含量随纬度升高而增加；不同海拔烟区烟叶的叶宽差异极显著，海拔1000～1100m烟区烟叶叶宽可达26．52cm；化学指标均呈现随海拔升高而降低的趋势，烟叶总氮、炯碱、类胡萝卜素和多酚含量、糖碱比的差异显著。

Middle tobacco leaves from variable geographic regions （Sangzhi, Fenghuang and Jingzhou） and regions with different altitudes in Xiangxi were used as materials to analyze the physical and chemical characteristics of tobacco leaves. The results showed that the differences in leaf width, rate of water content and thickness of tobacco leaves had reached significant level （P〈0.05）. Tobacco leaves from Sangzhi district has the longest leaf width （26.52 cm） and the highest rate of water content （18.98%）, while the most thick leaf appeared in Jingzhou （96.67 μm）. Tobacco leaves from different geographic regions in Xiangxi showed big differences in potassium, chlorine, total sugar, carotenoid and rutin contents, margin of two sugars, the ratio of potassium to chlorine, and the total sugar content increases with the reducing of altitude while the content of carotenoid and rutin increases with the rising of altitude. The difference of leaf width of tobacco leaves at different altitudes had reached significant level （P〈0.01）, with leaf width at altitudes of 1 000-1 100 m the highest （26.52 cm）. The differences in chemical indexes including total nitrogen, nicotine, carotenoid and polyphenols the ratio of total sugar to nicotine of tobacco leaves at different altitudes had reached significant level, these indexes all reduced with the rising of altitude.