Geographic distribution of soil water-soluble chlorine content and its relations to chlorine content in flue-cured tobacco leaves in Hunan tobacco-growing areas

A total of 1341 soil samples and 209 flue-cured tobacco leaf samples were collected from Hunan tobacco-growing areas, and their chlorine contents were determined. The soil water-soluble chlorine content in these areas ranged from 1.20 to 72.10 mg·kg-1, and averaged (13.55±7.75) mg·kg-1. 40.60% of the soil samples had a lower water-soluble chlorine content, with the lowest (8.88±8.04) mg·kg-1 in western Hunan. The chlorine content of flue-cured tobacco leaves was from 0.15% to 0.49%, and averaged 0.31%±0.09%. The chlorine content of different grades flue-cured tobacco leaves had a trend of X2FC3FB2F, but the difference was not significant. After soil samples were grouped according to their water-soluble chlorine content, a significant difference was found in the chorine content of corresponding flue-cured tobacco leaves. There was a significant linear relationship between the chlorine content of flue-cured tobacco leaves and the water-soluble chlorine content of soil (R2=0.8106,P0.01).