Distribution and Relationship of Nitrogen Content in Flue-cured Tobacco Leaf and Soil in Sanmenxia Tobacco Districts

The nitrogen contents in 159 flue-cured tobacco leaf samples and 238 soil samples in Sanmenxia tobacco districts were determined,and their distribution and relationship were analyzed.The results indicated that the nitrogen content in flue-cured tobacco leaf was suitable in total,which ranged from 0.85% to 2.53% with the mean of 1.46%±0.35%,and the nitrogen content in 43.39% of tobacco leaf samples was located in the range of 1.50%~3.00%;the order of the nitrogen content in different grades of flue-cured tobacco leaf was B2FC3FX2F.Total nitrogen content in the soil was high,which ranged from 0.37 g/kg to 1.58 g/kg with the mean of(0.76±0.15) g/kg,and the total nitrogen content in 6.38% of soil samples was more than 1.00 g/kg.Alkali-hydrolyzable nitrogen content was suitable,which ranged from 34.90 mg/kg to 132.74 mg/kg with the mean of(66.41±16.70) mg/kg,and 3.36% of soil samples had high alkali-hydrolyzable nitrogen content(≥110 mg/kg).The order of alkali-hydrolyzable nitrogen content in the soil of different counties was LingbaoShanxianLushiMianchi.The nitrogen content in flue-cured tobacco leaf had significant positive correlation at 0.05 level with alkali-hydrolyzable nitrogen content in soil,and the multiple regressive equations were built between the alkali-hydrolyzable nitrogen content in soil and the nitrogen content in flue-cured tobacco leaf.The nitrogen content in flue-cured tobacco leaf increased along with the increase of soil alkali-hydrolyzable nitrogen content.