关键词: 烤烟, 糖类衍生物, 糖醇螯合钾肥, 油分, 品质

Abstract: To investigate the effects of sugar derivatives application combined with potassium fertilizer on oil‑related indicators in upper tobacco leaves，Zhongyan 100 was used as the experimental material in a field trial. Spraying clear water served as the control（CK），with five additional treatments set as follows：spraying chitosan oligosaccharide（1.2 g/L，T1），glucosamine hydrochloride（1.5 g/L，T2），sugar alcohol chelated potassium fertilizer（600‑fold dilution，T3），chitosan oligosaccharide（1.2 g/L）+ sugar alcohol chelated potassium fertilizer（600‑fold dilution）（T4），glucosamine hydrochloride（1.5 g/L） + sugar alcohol chelated potassium fertilizer（600‑fold dilution）（T5）.Spraying was conducted every 10 days after topping，totaling three applications.Samples were collected to measure photosynthetic characteristics，oil‑related indicators，conventional chemical components，aroma compounds，and economic traits of the upper leaves of flue‑cured tobacco after application. Results indicated that co‑application of sugar derivatives with sugar alcohol chelated potassium fertilizer promoted photosynthesis and carbon‑nitrogen metabolism in upper tobacco leaves，with T4 treatment yielding the best effects. Compared to CK，photosynthetic rate and the activities of nitrate reductase，glutamine synthetase，sucrose synthase，and sucrase were significantly increased by 25.62%，28.01%，13.14%，24.44%，and 10.57%，respectively.Regarding oil content，the combined application of sugar alcohol chelated potassium fertilizer significantly increased the density，length，and secretion levels of glandular trichomes in the upper leaves of flue‑cured tobacco，with the T4 treatment showing the most pronounced effect.The content of α‑cembratriene‑diol and β‑cembratriene‑diol increased by 18.93% and 41.08%，respectively，compared to CK.Pyruvate and petroleum ether extract contents increased by 19.60% and 30.85%，respectively，compared to CK. In terms of conventional chemical composition，the treatment with sugar derivatives combined with sugar alcohol chelated potassium fertilizer resulted in higher levels of reducing sugars and total sugars and potassium in tobacco upper leaves. Specifically，the T4 treatment showed 21.38% increase in potassium content compared to CK.The total neutral aroma compounds in the upper leaves of flue‑cured tobacco treated with T4 and T5 increased by 26.88% and 19.78%，respectively，compared to CK.In terms of economic traits，the T4 treatment yielded the highest upper leaf production and value，reaching 1 105.41 kg/ha and 33 309.59 Yuan/ha respectively.These figures represented significant increases of 7.24% and 21.03% compared to CK.The proportion of premium‑grade tobacco rose to 49.27%，with an average price 12.85% higher than that of CK.In summary，the application of sugar derivatives in combination with sugar alcohol chelated potassium fertilizer promotes the growth and development of upper tobacco leaves，regulates carbon and nitrogen metabolism，balances the chemical composition of tobacco leaves，and increases the oil content and neutral aromatic compounds content in upper leaves.Among these，the combination of chitosan oligosaccharide with sugar alcohol chelated potassium fertilizer yields superior results.

Key words: Flue?cured tobacco, Carbohydrate derivatives, Sugar alcohol chelated potassium fertilizer, Oil content, Quality