Effects of Application of Medium and Trace Element Fertilizer and Biochar on Growth and Quality of Shiyan 1

Using field trials with three different basal fertilization pattern treatments, the agronomic traits of tobacco leaves at the mature stage and the chemical composition after curing under different basal fertilization patterns were determined. Single-factor ANOVA, correlation analysis, principal component analysis, and standardized principal axis analysis were used to analyze the above test data. The results showed that:(1) Increasing the application of medium and trace element fertilizer and medium and trace element fertilizer plus biochar as a base fertilizer was beneficial for increasing the leaf length, leaf width, leaf area, and plant height of tobacco. The application of medium and trace element fertilizer alone could increase the number of effective leaves, while the combined application of medium and trace element fertilizer and biochar could increase the dry weight of leaves. Increasing the application of medium and trace element fertilizer and medium and trace element fertilizer plus biochar was also beneficial for increasing the yield of tobacco leaves.(2) The application of medium and trace element fertilizers alone could reduce the contents of nicotine and chloride, and increase the contents of potassium, the nitrogen-alkaloid ratio, and the potassium-chlorine ratio. The combination of medium and trace element fertilizers with biochar could reduce nicotine content, increase total sugar, reducing sugar, and nitrogen contents, increase the nitrogen-alkaliod ratio, and reduce the potassium-chlorine ratio. The increasing application of medium and trace element fertilizers upon basal fertilizers can effectively improve the combustibility of tobacco leaves and bring the quality of tobacco leaves closer to the standard of high-quality cigars. Increasing the application of medium and trace element fertilizers, as well as the combined use of medium and trace element fertilizers and biochar with basal fertilizers, is beneficial for increasing the yield of tobacco leaves.