Relationship between the available copper content in soil and the copper content of flue-cured tobacco in Enshi tobacco-growing areas

【Objective】Based on the representative locations of different altitudes of Xuan′en and Xianfeng in Enshi tobacco-growing areas,the relationship between copper content in soil and flue-cured tobacco was analyzed.【Method】129 soil samples and 124 tobacco samples(contain Yunyan87,Yunyan85 and K326 which of three gradings of X2F,C3F and B2F) were selected to study the copper content in soil and copper content of flue-cured tobacco and their relationship.【Result】(1) The available copper content in soil in Enshi tobacco-growing areas ranged from 0.17 mg/kg to 9.88 mg/kg with the mean of(1.45±1.99) mg/kg,and the soil samples took a major proportion for the available copper content of ≥0.2~1.0 mg/kg.The available copper content in soil was closely related to pH.When pH was lower than 5.5,the available copper content in soil was the highest;when pH value was between 5.5 and 5.9,the available copper content in soil was the lowest;when pH was bigger than 5.9,the available copper content in soil was medium.The available copper content in soil decreased first,and then increased with altitude height(between 600 m and 1 500 m) going up.The available copper content in soil decreased with the soil depths deepening.(2) The copper content of flue-cured tobacco averaged(6.62±6.74) mg/kg,with amplitude of 1.26-34.30 mg/kg,and coincident frequency for Brazil's(4.90-10.60 mg/kg) was 29.31%.There existed significant differences among various cultivars,different gradings for the copper content of flue-cured tobacco,but not for the different altitudes.They showed the trends of Yunyan87K326Yunyan85,the trends of B2FC3FX2F,and the trends of lower altitude high altitudemiddle altitude respectively.(3) The copper content of flue-cured tobacco and the available copper content in soil both increased with the altitude height going up.The copper content of flue-cured tobacco increased as the available copper content in soil increased.In addition,the copper content of flue-cured tobacco and the available copper content in soil showed similar trends in different pH scopes.【Conclusion】There exists a positive correlation between available copper content in soil and copper content of flue-cured tobacco.