施钾量对不同生态区烤烟生长和钾肥利用率的影响

为研究不同生态区施钾量与烤烟生长和钾肥利用率的关系，以不施钾（CK）为对照，分别在气候和土壤差异明显的山东即墨和云南罗平开展了3个钾水平（即墨，T1 123.75 kg/hm²、T2 247.50 kg/hm²、T3 371.25 kg/hm²；罗平，T1 67.50 kg/hm²、T2 135.00 kg/hm²、T3 202.50 kg/hm²）的田间试验。结果表明：（1）施钾肥显著提高即墨烤烟茎、叶的生物量和总生物量，仅显著提高罗平烤烟烟叶生物量；T1、T2和T3显著提高烟叶生物量，即墨分别为7.62%、29.4%和31.5%，罗平分别为12.4%、19.5%和13.1%。（2）施钾肥显著提高即墨烟叶钾积累量和钾总积累量，T3效果最显著；显著提高罗平烤烟钾总积累量，T2效果最显著。（3）即墨施钾量与烤烟烟叶产量、烟叶钾含量和钾总积累量之间呈极显著正相关，而罗平则符合一元二次方程曲线；罗平T2对应施钾量下，烟叶产量、烟叶钾含量和钾总积累量与最大值（6579 kg/hm²、2.19%、230 kg/hm²）接近。（4）T2处理，即墨烟叶含钾量>3%，钾肥表观利用率（RE）和钾肥农学效率（AE）最高，分别为27.8%和2.50 kg/kg，钾肥偏生产力（PEP）降低，土壤钾素盈余显著；罗平RE高达45.3%，AE和PEP较高，分别为8.05 kg/kg和49.3 kg/kg，土壤钾素亏缺显著。综上，T2处理在提高即墨和罗平烟叶产质量和钾肥利用率以及平衡土壤钾素方面效果显著，可推荐为两地烤烟生产的适宜施钾量。

Effects of Potassium Application Rate on Growth and Potassium Use Efficiency of Flue-cured Tobacco in Different Ecological Regions

In order to study the relationship between potassium application rate in different ecological regions and growth and potassium use efficiency of flue-cured tobacco, field experiments were conducted in Jimo county of Shandong province and Luoping county of Yunnan province, which have different climate and soil conditions, the treatments designed included no potassium fertilizer applied (CK) and three application levels of potassium fertilizer (T1 123.75 kg/ha, T2 247.50 kg/ha, T3 371.25 kg/ha for Jimo; T1 67.50 kg/ha, T2 135.00 kg/ha, T3 202.50 kg/ha for Luoping). The results showed that (1) Potassium application caused significant increase in biomass of stems and leaves as well as total biomass of tobacco plants in Jimo, while only significant increase of leaf biomass was observed in Luoping. T1, T2 and T3 treatments caused significant increase of tobacco leaf biomass by 7.62%, 29.4% and 31.5% in Jimo and 12.4%, 19.5% and 13.1% in Luopin, respectively. (2) Potassium application significantly enhanced potassium accumulation in tobacco leaves and total potassium accumulation in tobacco plant in Jimo, with T3 having the most significant effect. Potassium application significantly enhanced total potassium accumulation in tobacco plants in Luoping, with T2 having the most significant effect. (3) In Jimo extremely significant positive correlations were observed between potassium application and yield of tobacco leaves, between potassium content in tobacco leaves and total potassium accumulation. In Luoping these relationships can be represented by quadratic equation curves. In Luoping potassium application rate, yield of tobacco leaves, potassium content of tobacco leaves and total potassium accumulation in tobacco plant of T2 treatment were close to the maximum (6579 kg/ha, 2.19%, 230 kg/ha). (4) For T2 in Jimo, tobacco leaves potassium content >3%, apparent utilization rate of potassium fertilizer (RE) and potassium agronomic efficiency (AE) were up to 27.8% and 2.50 kg/kg, potassium partial productivity (PEP) decreased, soil potassium surplus was significant. For T2 in Luoping, RE was as high as 45.3%, AE (8.05 kg/kg) and PEP (49.3 kg/kg) were higher, soil potassium deficiency was significant. In summary, the potassium application rate of T2 level had a significant effect in improving yield and quality of tobacco leaves, balancing soil potassium and improving the utilization rate of potassium fertilizer, and can be recommended as an appropriate potassium application rate for flue-cured tobacco production in the two regions.