Effects of Different Mg Fertilizer Levels on Dry Matter Accumulation and Nicotine Content of Flue-cured Tobacco

[Objective] The research aimed to study the effects of different Mg fertilizer levels on dry matter accumulation and nicotine content of flue-cured tobacco.[Method] Four treatments were designed,no Mg fertilizer treatment,the low Mg fertilizer treatment,the middle Mg fertilizer treatment and the high Mg fertilizer treatment,and the Mg fertilizer amount was 0,150,300,450 kg/hm2 respectively.Thereinto,the Mg fertilizer was MgSO4·7H2O.[Result] The Mg content of flue-cured tobacco leaf at different growth stages increased with the Mg fertilizer amount increasing.With the Mg fertilizer amount increasing,the dry matter accumulation amount of flue-cured tobacco leaf were more at the strongly growing stage and the mature stage,but nicotine content of flue-cured tobacco leaf decreased gradually.Mg fertilizer level had relatively less affected on the lower leaves,the middle affected on the middle leaves and the biggest affected on the upper leaves.[Conclusion] The study can provide the scientific basis for reasonably applying fertilizer in tabocco leaf production,impoving the nutrition status of tobacco plant,raising the yield ang quality of tobacco leaf.