Abstract:

In order to search after appropriate planting density and nitrogen application rate and to provide scientific guidance and reference applications for large area production, years of repeated field experiments were made in the main producing areas to compare the effects of different planting density and nitrogen application rate on yield and quality of sun-cured tobacco, the results showed that planting density, row spacing and nitrogen application all had influenced on yield, output value and smoking quality of sun-cured tobacco, among which nitrogen application rate showed much larger impact especially on the chemical composition and smoking quality than planting density and row spacing did. Therefore choosing an appropriate combination should be based on soil conditions. The results indicated that in the field of moderate nitrogen fertility, the appropriate nitrogen application rate should be 45-60 kg/hm2 cooperated with 60 cm of row spacing and 30 cm of distance between plants. Field with weak soil fertility nitrogen application rate could be 75 kg/hm2 or even 82.5 kg/hm2 when poor fertility, and the appropriate row spacing and distance between plants was 70 cm and 30 cm separately.