连续多年施用硫酸钾肥对烟田土壤及烟株硫素含量的影响

Effects of Successive Fertilization of Potassium Sulfate on Change of Sulfur Content in Soil and Tobacco Plant

为明确连续施用硫酸钾肥对烟田土壤及烟株硫含量及硫分配的影响,设置并开展了3年的硫酸钾肥定位试验。研究结果表明,根际土的有效硫含量受烤烟生育期及施肥量的影响较小,但根外土有效硫随施肥量的增加而增加,且以旺长期最高。土壤全硫含量受烟草根系及施肥量的影响,根际土中含量显著低于根外土,且两者均随施肥量的增加而显著增加(对照的根际土除外)。硫酸钾肥显著增加了叶部全硫含量及其积累量,并且随施用量的增加而增加;其对茎部的影响次之,对根部影响最小,但施肥量对成熟期各部位全硫分配率的影响较小。连续3年施用含硫量达125.4 kg/hm2的肥料后,各叶位的含硫量均达到0.7%及以上。因此,应根据烟田土壤及烟叶硫含量的实际情况,合理规范硫酸钾类肥料在烟草生产中的施用量。

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/hm2 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.