Abstract:
In order to evaluate the effect of successive fertilization of potassium sulfate on change of sulfur (S) content in soil and tobacco plant, a 3 year continuous fertilization field experiment was established and analyzed. The results showed that the soil available S content in rhizosphere of tobacco changed little with the growth stages and the fertilizer rates, but it increased with the S fertilizer rates, and decreased with the growth stages in out-rhizosphere, with the highest values at the vigorous growth stage. The total soil S was significantly affected by tobacco root and the S fertilizer rate. The total S content in rhizosphere was obviously lower than that in out-rhizosphere, and both of them increased with the S fertilizer rates except for the rhizosphere soil in CK. The application of potassium sulfate fertilizer significantly increased the total S content and its accumulation in leaves, and they both increased with the S fertilizer rates in general. But it had less effect on stem, and the least on root. Moreover, the S fertilizer rate dad little influence on the distribution of total S in each part of tobacco at maturity stage. After 3 year's application of sulfate fertilizer with 125.4 kg/hm
2 per year in this study, the total S content at different leaf positions reached at 0.7% or above, which was the critical valve affecting the quality of tobacco leave. In conclusion, the S fertilizer rates in tobacco plantation should be adjusted reasonably according to the soil condition and the S content in tobacco leaves in the future.