夜温升高对云南省高海拔烤烟理化特性及产、质量的影响

Effects of nighttime temperature increase on physio-chemical properties, yield and quality of flue-cured tobacco in high-altitude region of Yunnan Province

以‘云烟87’和‘K326’为材料,采用大田试验,研究了夜间温度升高对云南省高海拔不同烤烟品种烤后烟叶物理特性及常规化学成分、Cu、Zn、Fe、Mn含量和经济性状、感官评吸质量的影响,旨在探讨温度对烤烟理化特性及内在品质的影响,为云南省烟区烤烟风格特色的形成机理研究提供理论依据。试验采用单因素随机区组设计,设置2个温度处理:1夜间保温,每日18:00—次日6:00大棚封闭升温,试验期间大棚内夜间平均温度为16.7℃;2自然夜温(对照),试验期间夜间平均温度为15.5℃。研究结果表明:1)夜温升高使‘K326’和‘云烟87’上部叶长宽、下部叶叶长,‘K326’上部叶单叶重和平衡含水率、中部叶单叶重均显著增加;‘K326’中上部叶、‘云烟87’中下部叶叶片厚度以及‘K326’各部位、‘云烟87’上部位叶片含梗率均显著降低。2)‘K326’中上部叶总糖、还原糖、总氮,‘云烟87’各部位叶总氮、钾均较对照显著增加;同时使‘K326’中上部叶烟碱和钾、下部叶总氮,‘云烟87’上部叶总糖、还原糖和烟碱及中部叶烟碱和下部叶总糖、还原糖均显著降低。3)‘K326’上部和下部烟叶Zn、Cu含量较对照显著降低,Fe、Mn含量较对照显著提高;‘云烟87’上部叶Zn、Cu、Fe、Mn含量较对照均显著提高。4)‘K326’产量、产值、均价、上等烟比例分别较对照增加252.5 kg·hm-2、7 290元·hm-2、1.7元·kg-1、6.54%;‘云烟87’分别增加100.5 kg·hm-2、5 315元·hm-2、2.1元·kg-1、4.65%。综上所述,夜温升高可以显著改善云南省高海拔地区烤后烟叶的物理特性,内在化学成分趋于协调,产值产量显著增加,烟叶工业可用性进一步提升。

This study used tobacco cultivars of ‘Yunyan 87’ and ‘K326’ to analyze the effect of nighttime temperature increase on physio-chemical properties, yield and quality of flue-cured tobacco in high altitude region of Yunnan Province. Through field experiment, the study evaluated the effects of nighttime temperature rise on the physical characteristics, chemical composition, micronutrients contents, economic characteristics, and sensory quality of tobacco. The study aimed to explore and improve the physical and chemical properties as well as inherent quality of flue-cured tobacco by the adjustment of ecological factors （temperature in this study）. Based on the single factor randomized block design pot experiment, two temperature treatments were＆amp;nbsp;established. The first temperature treatment was to artificially keep warm at nighttime （18：00–6：00） under greenhouse condition. During this treatment, average nighttime temperature in the greenhouse was maintained at 16.7℃. The second temperature treatment was to keep a natural temperature in the greenhouse for purpose of comparison. In this treatment, the average natural temperature at night was 15.5℃.The study showed that rising nighttime temperature broadened the upper leaves and lengthened the lower leaves of ‘K326’ and ‘Yunyan 87’. It also significantly increased single leaf weight and equilibrium moisture content of the upper leaves along with the single leaf weight of the middle leaves of ‘K326’. With the rise in nighttime temperature, leaf thickness significantly decreased for the middle and upper leaves of ‘K326’ and the middle and lower leaves of ‘Yunyan 87’. Also leaf stem content significantly decreased for all the leaves of ‘K326’ and the upper leaves of ‘Yunyan 87’. Compared with those under natural nighttime temperature treatment, the contents of total sugar, reducing sugar and total nitrogen increased drastically in the middle and upper leaves of ‘K326’ under increased nighttime temperature treatment. Also the contents of total nitrogen and potassium increased in all the leaves of ‘Yunyan 87’. However, decreases in the contents of nicotine and potassium in the middle and upper leaves of ‘K326’ were noted. Also the decreases in the total nitrogen in the lower leaves of ‘K326’, in the contents of total sugar, reducing sugar and nicotine in the upper leaves of ‘Yunyan 87’, in the content of nicotine in the middle leaves of ‘Yunyan 87’, and in the contents of total sugar and reducing sugar in the lower leaves of ‘Yunyan 87’ were observed too. Under nighttime temperature increase treatment, the contents of Zn and Cu significantly decreased while those of Fe and Mn increased in the upper and lower leaves of ‘K326’, compared with those under the natural temperature treatment. Also the contents of Zn, Cu, Fe and Mn increased in the upper leaves of ‘Yunyan 87’. Compared with the natural temperature treatment, nighttime temperature increase treatment improved output, output value, average price and fine tobacco proportion of ‘K326’ respectively by 252.5 kg·hm？2, 7 290 Yuan·hm？2, 1.7 Yuan·kg？1 and 6.54%. Similarly, these variables of ‘Yunyan 87’ increased respectively by 100.5 kg·hm？2, 5 315 Yuan·hm？2, 2.1 Yuan·kg？1 and 4.65%. Thus increasing nighttime temperature significantly improved the physical characteristics, chemical component, production output and industrial value of flue-cured tobaccos in high altitude region of Yunnan Province.