Effects of Different Amount of Magnesium Fertilizer on the Growth, Yield and Quality of Flue-cured Tobacco in Sangzhi County of Hunan Province

Purpose In order to study the different amount of magnesium fertilizer on growth, yield and quality of flue-cured tobacco.

Method A single factor randomized block field experiment was carried out with different amount of magnesium fertilizer 0, 125, 250, 375, 500 kg/hm², by using Yunyan 87 as the test material.

Results The application of magnesium fertilizer could promote the growth and development of flue-cured tobacco, and improve the plant height, maximum leaf width, maximum leaf area, stem girth and leaf number of flue-cured tobacco. The application of magnesium fertilizer could improve the quality of tobacco leaves, reduce the content of nicotine (decreased by 0.21%-0.67%) in the upper leaves and regulate the content of chlorine (decreased by 0.02%-0.06%) and potassium (increased by 0.01%-0.64%), and promote the total sugar content. The contents of reducing sugar, total nitrogen, sugar nicotine ratio, nitrogen nicotine ratio and potassium chlorine ratio became suitable of tobacco leaves after baking. The application of magnesium fertilizer could also significantly increase the economic benefits (the output value increased by 2 574.12-11 171.12 yuan/hm²) of flue-cured tobacco leaves. But it had different effects on the different levels of magnesium fertilizer application that the effect of lower level (125 kg/hm²) or higher level (375-500 kg/hm²) of magnesium fertilizer application on the growth, yield and quality of flue-cured tobacco was not good enough.

Conclusion It was more suitable that the magnesium fertilizer application at the medium level of 250 kg/hm² in Sangzhi County of Hunan Province tobacco area.