Abstract:
A five year field experiment was conducted to investigate the effects of returning organic fertilizers to field continuously on leaf quality of flue-cured tobacco and soil physical and chemical properties. The results showed that, after applying organic fertilizers for 4 years, soil bulk density decreased 0.1 g/cm3. The number of actinomycetes, nitrifier, and nitrosobacteria in soil increased 6.1, 12.1, and 11.5 times, respectively. After applying organic fertilizers for 5 years, the yield of tobacco leaf increased 38.9%, the value increased 23.9%, the leaf composition became more harmonized, the sense and smoking tests results improved remarkably, and the soil organic matter increased 0.26%. By returning organic fertilizers to field continuously, the Cl content of the soils and tobacco leaves increased slightly and then stabilized in the appropriate ranges, and tobacco leaves could mature normally. In conclusion, long term application of organic fertilizers have remarkable effects on tobacco production.