Abstract:
In order to explore a fertilization method that should be more conducive to improving the quality of tobacco leaves in Shandong flue-cured tobacco growing areas. In 2018, a combination of potted and field trials was used in the main tobacco areas of Shandong to compare the effects of the combined applications of organic and inorganic fertilizers and those with different amounts of biochar on the growth and development of flue-cured tobacco and the quality of tobacco leaves. The results showed that the OFB1 and OFB2 treatments were better than the OF treatment on promoting the establishments of tobacco plant height, stem circumference and leaf area, increasing tobacco plant biomass by 0.7%-11.06%, especially in the leaf dry weight, and increasing total sugar, reducing sugar and potassium content of the central tobacco leaves by 1.47%-6.91%, 1.02%-4.33%, and 0.1%-0.53%, respectively. Also, they increased total sugar, reducing sugar and potassium content of the upper tobacco leaves by 0.42%-6.55% and 1.47%-0.53%, and 0.07%-0.31%, respectively, significantly increased the ratios of sugar to nicotine and potassium-chlorine of the central tobacco leaves by 0.15-1.81 and 0.3-1.06, respectively, and significantly increased the ratios of sugar to nicotine and potassium-chlorine of the upper tobacco leaves by 0.41-1.55 and 0.82-1.49, respectively. Moreover, they significantly increased the proportion of high-class tobacco leaves in the middle and upper parts of flue-cured tobacco by 2.12%-15.58% and 4.83%-11.79%, respectively, increasing the average price of the corresponding tobacco leaf of flue-cured tobacco by 0.30-1.90 and 0.50-0.73 yuan kg
−1, respectively. Comprehensive analysis of the effects of different fertilization methods on the growth and development of flue-cured tobacco, the quality and economic characteristics of tobacco leaves, it was preliminarily believed that the method of additional application of 3-5 t hm
−2 biochar under the application of organic and inorganic fertilizers was more conducive to further improving the quality of tobacco leaves in Shandong tobacco-growing areas.