Analysis of altitude adaptability of main flue-cured tobacco varieties in Kunming City

Ecological conditions greatly influence tobacco leaf quality, and elevation is a comprehensive index for ecological analysis. It is therefore critical to study the effect of altitude on tobacco leaf quality so as to guide three-dimensional optimization layout of flue-cured tobacco varieties. In this study, altitude adaptability of tobacco varieties of 'K326', 'Honghuadajinyuan' and 'Yunyan 87' were determined in 4 main tobacco growing townships in Shilin County and Yiliang County, Kunming City. Data were collected in experiments conducted at 12 sites at every 200 m in the altitude range of 1 400?2 200 m, where cultivation practices were largely consistent. The effects of altitude on physical properties, chemical properties and smoking quality of flue-cured tobacco were determined. The result suggested that the sensitivity of flue-cured tobacco varieties to altitude decreased in order as follows: 'Honghuadajinyuan' > 'K326' > 'Yunyan 87'. Also the chemical components of leaves were more sensitive to altitude than the physical properties and smoking quality of leaves. In the 1 400?2 200 m altitude range, altitude was significantly or extremely significantly correlated (negative) with leaf opening degree, total nitrogen content, nicotine content, potassium content, chlorine and main polyphenols contents. Also in the 1 400?2 200 m altitude range, altitude was significantly or extremely significantly correlation (positive) with moisture content, total sugar and reducing sugar contents and irritancy. In summary, the integrated analysis showed that leaf chemical components, polyphenol content and aroma properties of 'K326', 'Honghuadajinyuan' and 'Yunyan 87' were optimum at an altitude range of 1 400 1 800 m in Kunming City. Tobacco leaf quality decreased in order as follows: 'Honghuadajinyuan' > 'K326' > 'Yunyan 87'.