Abstract: Tobacco is a potassium-addicted crop. Facing the shortage of potassium resources in China, it is necessary to clarify the best way of applying potassium to tobacco and improve the utilization efficiency of potassium. Using the field plot test method, Yuyan 6 as the research material, this paper carried out five experimental treatments according to the application of potassium and auxin, and studied the effects of different treatments on the physical properties, appearance quality, conventional chemical composition and neutral aroma content of flue-cured tobacco. The results showed that: ①compared with CK, the treatment (applying potash fertilizer three times+applying auxin) could obviously improve the agronomic and physical characters of tobacco plant, and improve the score of appearance quality of flue-cured tobacco leaf. ② The potassium content and neutral aroma content of tobacco leaf increased by 55.88% and 10.89%, respectively, after applying potash fertilizer three times+ applying auxin. The yield, output value and the proportion of medium and upper tobacco were significantly higher than CK.③ Through the correlation analysis between the content of potassium and neutral aroma substances in flue-cured tobacco leaf, it was found that there was a significant positive correlation between potassium content and some products in neutral aroma substances, indicating that increasing potassium content could effectively increase neutral aroma substances content. The treatment (application of potassium fertilizer, topping application of plant growth regulators) was more conducive to improve the agronomic traits of tobacco leaf, it was the best way to apply potassium to tobacco.

Key words: flue-cured tobacco, potassium application period, auxin, agronomic traits, yield and quality

摘要： 烟草是嗜钾作物，面对我国钾资源短缺的问题，必须明确烟草施钾的最佳方式，提高钾素的利用效率。采用田间小区试验法，以豫烟6号为研究材料，依据施钾时期和涂抹生长素设置5个试验处理，研究不同处理对烤后烟叶物理性状、外观质量、常规化学成分和中性致香物质含量等指标的影响。结果表明：①与对照相比，分三次施用钾肥+涂抹生长素处理可以明显改善烟株的农艺性状和物理性状指标，提高烤后烟叶外观质量评分；②分三次施用钾肥+涂抹生长素处理烤后烟叶钾素含量和中性致香物质含量较对照分别增加了55.88%和10.89%，产量、产值及中上等烟比例较对照显著提高；③通过烤后烟叶钾素和中性致香物质含量相关性分析得出，钾素含量与中性致香物质中部分产物存在显著正相关性，表明提高钾素含量可以有效增加中性致香物质含量。分三次施用钾肥并打顶施用植物生长调节剂处理更有利于改善烟叶的农艺性状指标，是烟草的最佳施钾方式。

关键词: 烤烟, 施钾时期, 生长素, 农艺性状, 产质量