Effects of Integrated Water and Fertilizer Management on Growth, Yield and Quality of Flue-cured Tobacco in Zhaotong Tobacco-growing Areas

To explore the suitable drip irrigation and integrated water-fertilizer technology model for flue-cured tobacco in Zhaotong tobacco-growing areas, field experiments were conducted in four counties and districts of Zhaotong City, including Ludian, Qiaojia, Yiliang and Yongshan. With conventional fertilization as the control (CK), three treatments were designed: drip irrigation + conventional fertilization (S₁), 20% base fertilizer+80% integrated water-fertilizer topdressing (S₂), and whole-process integrated water and fertilizer management (S₃). The effects of different models on the growth process, agronomic traits, disease occurrence, economic traits, chemical components and sensory quality of flue-cured tobacco were studied. The results showed that compared with CK, the integrated water-fertilizer treatments (S₁, S₂ and S₃) promoted early and rapid growth of tobacco plants, shortened the field growth period by 3~9 days, and significantly improved agronomic traits. S₂ had the best performance in plant height, stem girth and middle leaf area, effectively reduced the disease index of tobacco viral diseases such as TMV and PVY, improved economic benefits, and achieved the highest output value at most experimental sites. The proportion of high-grade tobacco under S₃ at Qiaojia site reached 76.03%, the chemical components of tobacco leaves were coordinated. The chloride ion content of each treatment decreased by 0.17~0.43 percentage points compared with CK, and the potassium-chloride ratio optimized. The sensory smoking quality was stable, and some treatments were slightly improved in aroma quality and cleanliness. The popularization and application of drip irrigation and integrated water-fertilizer technology in Zhaotong tobacco-growing areas, especially the model of 20% base fertilizer+80% water-soluble fertilizer topdressing (S₂), can promote the growth and development of flue-cured tobacco and improve yield, quality and economic benefits.