Abstract:

To study the effects of different soil improvement materials on the yield and quality of flue-cured tobacco and the chemical properties of tobacco-planting soil, the relationship between the changes of soil chemical properties and the yield and quality of flue-cured tobacco during the growth and development of flue-cured tobacco was explored to provide theoretical basis and technical support for the production of high-quality tobacco leaves in Luliang tobacco area. In this experiment, ‘Yunyan 121’ was selected as the test variety, and there were 4 treatments (S₀: local conventional fertilization treatment; S₁: application of lime 60 g/plant; S₂: application of biochar 100g/plant; S₃: application of earthworm manure 200 g/plant). Through the investigation and analysis of the soil chemical properties, agronomic traits and yield and quality and other aspects of performance of ‘Yunyan 121’ under different treatments, the effects of different soil improvement materials on flue-cured tobacco and tobacco planting soil were comprehensively evaluated. The results showed that the growth of flue-cured tobacco with biochar was the best, followed by earthworm manure. In terms of disease, the incidence of vermicompost application was reduced by 32.49% compared with the control, and the disease index was reduced by 25.2% compared with the control. In terms of soil physical and chemical properties, compared with the control group, the application of biochar significantly increased the content of available potassium in soil and significantly reduced the content of chloride ion in soil. In terms of economic traits, the output value, average price, and proportion of middle and upper tobacco treated with earthworm manure increased by 9.7%, 19.4%, and 13.4%, respectively, compared with the control group. In terms of chemical composition of flue-cured tobacco leaves, the application of biochar had the best coordination effect. The chloride ion content decreased to 0.36 mg/kg, which was 50.7% lower than that of the control group, and the potassium content reached 2.89 mg/kg, which was 16.4% higher than that of the control group. In summary, the application of 100 g/plant biochar contributes to the improvement of tobacco-planting soil, the balance of soil nutrients, the promotion of tobacco plant growth, and the improvement of flue-cured tobacco quality, among which the effect of increasing potassium and reducing chlorine is particularly significant; the application of 200 g/plant earthworm manure could effectively enhance the disease resistance of flue-cured tobacco and improve the economic traits of flue-cured tobacco leaves. Under the conditions of this experiment, the combined application of biochar and earthworm manure for soil improvement can effectively reduce the content of chloride ions in tobacco leaves, improve the quality of tobacco leaves, enhance the chemical coordination of tobacco leaves, and improve economic benefits, which was conducive to pursue highest yield and suitable cultivation.

Key words: tobacco planting, soil improvement, chemical properties, yield and quality, flue-cured tobacco, biochar, vermicompost, tobacco leaf quality, economic traits