Relationship between Potassium Content and Aroma Components of Flue-cured Tobacco in Yunnan

204 flue-cured tobacco samples were collected in Yunnan Province. The relationship between potassium content and aroma components of flue-cured tobacco were analyzed using correlation analysis, gray correlation analysis and regression analysis. The results indicated that, the mean potassium content was 1.96% with a variation between 0.70%-3.24%, with 52.45% of the samples having low potassium content. Significant difference in potassium content of flue cured tobacco was observed between elevation groups and soil pH groups. The variation in flue-cured tobacco aroma components was huge in Yunnan (3.41-10.50 times), and the aroma components were highly significantly correlated with potassium content, with the order of grey incidence coefficients being: ketones >aldehydes >alcohols >nitrogen heterocyclic >phenols >esters. Potassium content and all the aroma component conformed to linear equations with at the extremely significant level, that is, with the increase of flue cured tobacco potassium content, a linear increase of aroma components was observed. Aroma components of the lowest potassium content group (potassium content is 0.97%) was 71.89 μg/g (30.77%) less than that of the highest potassium content group (potassium content is 2.96%). Potassium nutrition is an important factor that affects the aroma components in Yunnan flue-cured tobacco.