Geographic Distribution of Chlorine Content in Soil and Flue-cured Tobacco and the Relationship between them in Tobacco-growing Areas of Central Henan

Purpose In order to study the geographic distribution of the chlorine content in soil and flue-cured tobacco and their relationship in the tobacco-growing areas of Central Henan.

Method A total of 117 soil and flue-cured tobacco leaf samples were analyzed by canonical correlation analysis.

Results The soil water-soluble chlorine content among the whole tobacco-growing areas ranged from 7.10 to 84.77 mg/kg, mean value of three areas was as follows: Pingdingshan 36.96 mg/kg, Xuchang 33.14 mg/kg, Luohe 33.43 mg/kg; the chlorine content in flue-cured tobacco ranged from 0.01% to 1.07%, the chlorine content of tobacco from Pingdingshan, Xuchang and Luohe were 0.32%, 0.41%, 0.43% respectively, the chlorine content in flue-cured tobacco was appropriate at most of the areas; the sample proportion of Pingdingshan, Xuchang, Luohe were in very low and low ranges were 13.95%, 15.56%, 10.35% respectively, which all met the needs of high-quality tobacco production, had 32.56% and 33.33% of the soil chlorine content samples in Pingdingshan and Xuchang were in the appropriate range, 53.49% and 51.11% of samples were relatively high; and the chlorine content in soil in Luohe area accounted for 24.14% in suit group and 65.51% in high group, the coefficient of variation among three regions from large to small was Luohe > Pingdingshan > Xuchang. There was a significant linear relationship between the chlorine content of flue-cured tobacco leaves and the water-soluble chlorine content of soil ( R²=0.953 3, P<0.01).

Conclusion In order to regulate flue-cured tobacco chlorine content better in the tobacco-growing areas of Central Henan, the soil chlorine content should be considered first, and other factors like climate, altitude also should be considered at the same time.