连作对烤烟化学成分和中性致香物质的影响

分析了重庆烟田连作对烤烟化学成分和中性致香物质的影响。结果表明,随着连作年限的增加,烟叶中烟碱、蛋白质、总氮含量均明显增加,总糖和还原糖的含量呈明显下降趋势;烟叶中施木克值、两糖比和糖氮比有明显的下降趋势,氮碱比、钾氯比变化不明显。石柱、南川和奉节烤烟烟叶中中性致香物新植二烯、茄酮、β-大马酮含量较高,类胡萝卜素类物质降解产物最多。3县烤烟总中性致香物含量以南川为最高(728.90～858.72μg/g),其次为奉节(558.25～680.50μg/g)和石柱(520.73～637.13μg/g)。新植二烯、类胡萝卜素类和苯丙氨酸类致香成分随连作阶梯下降,类西柏烷类和棕色化产物总体上呈现降低趋势,在不同茬次间均表现出头茬和重茬的差距小,漏茬和多茬变化明显的规律。

Effect of Continuous Cropping on Chemical Composition and Neutral Aroma Components of Flue-cured Tobacco

The effect of continuous cropping on the chemical composition and neutral aroma components of flue-cured tobacco in Chongqing tobacco fields was analyzed.The results indicated that along with the increase of cropping years,the nicotine,protein and total nitrogen content in tobacco leaves showed a marked increasing trend,total sugar and reducing sugar content revealed a significant downtrend,schmuck value,two sugar ratio and the ratio of sugar to nitrogen dropped significantly,while the ratio of nitrogen to alkali and the ratio of potassium to chloride had no obvious change.In the three tobacco regions,neophytadiene,solanone and β-damascenone had a high content,and carotenoids had the most degradation products.When the continuous cropping years prolonged,the total content of neutral aroma components in the leaves of flue-cured tobacco decreased in the three tobacco regions,in which the highest content(728.90～858.72 μg/g)was found in Nanchuan,followed by Fengjie(558.25～680.50 μg/g) and Shizhu(520.73～637.13 μg/g).The neophytadiene,carotenoids and phenylalanine aroma components lowered year by year,and cembrane aroma and brown reaction products generally showed a decreasing tendency,and different stubbles all showed the following law: the content between the first and second stubble had no obvious difference,and that between the third and multiple stubble had marked difference.