【摘要】 为探究不同打顶时期对上部烟叶内在质量的影响,并为今后云南昭通地区烟叶优质生产提供打顶技术理论依据,本试验以云烟87为试材,研究不同打顶时期对烤烟农艺性状、经济性状及上部烟叶化学成分、香气前体物质的影响。结果表明:初花打顶处理的烟叶叶长、叶宽及叶面积系数最大,分别为53.98 cm、21.61 cm和2.763;烟叶产量最高,为2 083.5 kg/hm~2;产值、均价也最高,分别为每公顷41 624.85元、每千克30.75元。随着打顶时间的推迟,总糖含量逐渐增加,还原糖、总氮及烟碱含量逐渐减少;烟叶多酚类物质及非挥发性有机酸含量逐渐增加,香气前体物质含量逐渐增加。随着打顶时间的推迟,各处理上部烟叶总糖含量在打顶20 d后出现显著变化,烟叶总糖含量最终为T3>T2>T1;各处理还原糖含量在打顶20 d后出现显著变化,烟叶还原糖含量最终为T3>T2>T1;各处理淀粉含量在打顶10 d后出现显著变化,最终为T1>T2>T3。同时,初花打顶后烟叶的感官评吸质量分数最高为78.5。因此,初花打顶有利于烟叶香气前体物质含量的增加,使内在化学成分更加协调,烟叶内在质量更好。更多还原

【Abstract】 The study was conducted to explore the effects of different topping time on the internal quality of upper tobacco leaves, furthermore, to provide theoretical bases for the high-quality tobacco production in Zhaotong areas of Yunnan Province in future. We chose the tobacco cultivar Yunyan 87 as experimental material to study the effects of topping at budding(T1), initial flowering(T2) and full blooming(T3) stages on the agronomic traits, economic characters, chemical compositions and precursor of aroma. The results showed that the leaf length, leaf width and leaf area index of tobacco topping at initial flowering stage were maximum with the values of 53.98 cm,21.61 cm and 2.763 respectively,and the yield as 2 083.5 kg/hm~2 was the highest, meanwhile, the output value and average price of tobacco leaves reached the maximum as 41 624.85 yuan/hm~2 and 30.75 yuan/kg respectively. With the delay of the topping period, the total sugar content increased gradually, but the contents of reducing sugar, total nitrogen and nicotine decreased gradually, and the contents of polyphenol, non-volatile organic acid and aroma precursor in the tobacco leaves increased gradually. The total sugar content of upper leaves under different treatments appeared significantly change after 20 days of topping, and finally showed as T3﹥T2﹥T1. The reducing sugar content of tobacco leaves changed significantly after 20 days of topping, and the final order was T3﹥T2﹥T1. The starch content also changed significantly after 10 days of topping, and finally showed as T1﹥T2﹥T3. At the same time, the sensory score of T2 treatment was the highest as 78.5. Therefore,topping at initial flowering stage was beneficial to the increase of aroma precursor content, which also could coordinate internal chemical composition and improve internal quality.更多还原