Relationships between the selenium content in flue-cured tobacco leaves and the selenium content in soil in enshi,China tobacco-growing area

Relationships between the selenium content in flue-cured tobacco leaves and the selenium content in soil in enshi tobacco-growing area were analyzed. the results indicated that: (1) the selenium content in flue-cured tobacco leaves in enshi was high,ranging from 0.30 to 29.30 mg·kg-1 with the mean of (8.37±5.83) mg·kg-1.the content of selenium in flue-cured tobacco among different positions was x2f>c3f>b2f,among different altitudes was medium altitude(800m~1200m)>high altitude(≥1200m)>low altitude (<800m). (2) the selenium content in soil in enshi tobacco-growing area was high,ranging from 0.28 to 7.03 mg kg-1 with the mean of (2.56±1.64) mg kg-1. most of the soil was selenium-rich and high-selenium soil,and 34.44% of soil was excessive-selenium soil. as the soil thickness deepened,the selenium contents in soil became lower and lower,and the same trend was observed in the selenium content of flue-cured tobacco leaves at different altitudes. (3) there was significantly positive-correlation between the selenium content in soil and the selenium content of flue-cured tobacco leaves (correlation coefficient was 0.949). based on the correlation analysis,the regression equation,ŷ = -0.1082x3 +1.2494x2 -1.9628x + 8.1647 was established between soil available selenium and the selenium content in flue-cured tobacco leaves for 72 samples. regression equation reached a significant level by f-test.