Effects of Different Flue-curing Barns on Aroma Quality of Upper Flue-cured Tobacco Leaves of K326

[Objective] This study was conducted to compare the aroma quality of up-per leaves of K326 flue-cured in different barns, and provide theoretical references for the development and optimization of bulk curing barn and the supporting tech-niques. [Method] The upper leaves of K326 were flue-cured in a commonness barn, a four-shelf bulk curing barn and a three-shelf bulk curing barn separately, and then the contents of aroma components and taste quality indices of the finished leaves were measured and compared. [Result] The contents of total aroma components, chromoplast pigment degradation products, phenylalanine aroma components and neophytadiene showed no significant differences in the leaves flue-cured in four-shelf bulk curing barn and commonness barn, but were significantly or very significantly higher than those in the leaves flue-cured in three-shelf bulk curing barn. The con-tents of carotenoid degradation products, Mail ard reaction products, cembranes aro-ma components and total aroma components （except neophytadiene） showed no significant difference among the three treatments. The results of sensory evaluation revealed that the sensory taste of the leaves flue-cured in four-shelf bulk curing barn was the best, as the finished leaves had rich, delicate aroma, comfortable and clean aftertaste. The leaves flue-cured in commonness barn was better than those flue-cured in three-shelf bulk curing barn in aroma quality, amount and aftertaste. [Conclusion] The four-shelf bulk curing barn had a large volume for tobacco leaf processing, but a similar baking environment to the commonness barn, which is conducive to the formation and accumulation of aroma components, so the finished leaves had similar appearance and quality with those flue-cured in commonness barn. The upper flue-cured leaves in three-shelf bulk curing bran had poorer quality than those flue-cured in the other two barns.

Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Stepwise Discriminant Analysis

[Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method] The aroma types of tobacco leaves were judged based on stepwise discriminant analysis, using 63 C3F and 65 B2F tobacco leaf samples from 13 tobacco producing regions in 11 provinces of China （Huili in Sichuan, Baokang in Hubei, Wulong in Chongqing, Lu- oyang in Henan, Zhucheng in Shandong, Wuyi Mountain in Fujian, Malong in Yun- nan, Chuxiong in Yunnan, Bijie in Guizhou, Liuyang in Hunan, Suiyang in Guizhou, Kaiyuan in Liaoning, Nanxiong in Guangdong） as calibration samples, and 67 aroma components as indices. And the Fisher discriminant functions were verified using 21 C3F and 19 B2F tobacco leaf samples. [Result] Variation coefficients of the propor- tions were lower than that of contents of most aroma components in middle and upper leaves of the samples, indicating that the proportions were more stable than contents of aroma components. The proportions of benzyl alcohol, solanone, β-dam- ascone, neophytadiene, farnesylacetone A, palmitic acid, thunbergol, methyl linole- nate and cembratriene-diol were all over 1% in both middle and upper leaves, al- though the dominant aroma components of the same aroma type varied between middle and upper leaves. Moreover, 11, 18, 7 and 11 aroma components were re- spectively introduced into the Fisher discriminant functions established based on the contents and proportions of middle and upper flue-cured tobacco leaves, which ex- hibited accuracy rates of 91.7%, 100%, 91.7% and 91.7% in the judgments of other tobacco leaf samples. The results revealed that the components those determined aroma types in middle leaves were obviously more than in upper leaves. In middle leaves, the accuracy rates of aroma type judgment could be improved by using the proportions rather than the contents of aroma components as indices. However, the functions based on the proportions and the contents of aroma components in upper leaves gave close accuracy rates. [Conclusion] The results of the study will provide references for identifying aroma types of flue-cured tobacco leaves in future work.

Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Proportions of Aroma Components

[Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples （63 C3F and 65 B2F） from 11 main tobac- co production provinces of China were selected as materials. Stepwise discriminant analysis was applied to samples with different aroma types and discriminant function was expressed with the proportions of 67 aroma components in total aroma con- stituents as the index. [Result] The ratio of most aroma components in clear and full aroma tobacco leaves was higher than that in middle aroma leaves. The ratios of 51, 43 and 40 aroma components of clear, middle and full aroma tobaccos were higher in upper leaves than that in middle leaves. Aroma components dominated certain aroma types differed between middle and upper leaves. The proportions of 18 and 11 aroma components in upper and middle leaves were led in the stepwise discriminant function respectively. Self-validation and cross-validation methods were applied to evaluate the original samples, and the accuracy rates reached 100% and 98.6% on middle leaves, 96.37% and 94.4% on upper leaves. The accuracy rates on some other samples reached 100% on middle leaves and 91.7% on upper leaves predicted with the model. [Conclusion] The ratio of aroma components as discriminant index could improve discriminant accuracy significantly in the middle and upper leaves. It could be used to analyze aroma types objectively, accurately and quickly.

Effects of Different Transplanting and Harvest Dates on Yield and Quality of Flue-cured Tobacco Leaves

In this study,the effects of nine different combinations of transplanting and harvest dates on yield and quality of flue-cured tobacco leaves were investigated.The results showed that different combinations of transplanting and harvest dates had few effects on growth period and agronomic characters of tobacco plants but exerted remarkable effects on economic characters and chemical composition of flue-cured tobacco leaves.With the postponing of transplanting stage,output value of flue-cured tobacco leaves increased.Output value of flue-cured tobacco leaves in C1treatment（normal harvest） was higher than that in C2（harvest 7 d later） and C3（harvest 14 d later） treatments.Different combinations of transplanting and harvest dates had significant effects on chemical composition of flue-cured tobacco leaves,which exhibited no obvious law.Overall,flue-cured tobacco leaves in T3C1treatment（transplanting 14 d earlier,normal harvest） displayed excellent performance compared with other treatments.

Effects of Exogenous Amylases and Metal Ions on the Amylase Specific Activities and Starch Degradation of the Upper Leaves of ‘KRK_(26)' during Flue-curing

Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2＋, Mn2＋ and K＋ on the amylase specific activities and starch degradation of the upper leaves of ＇KRK26＇ planted in Yunnan Province during flue-curing. [Method] The amylase specific activities and starch degradation of the leaves were determined by using spectrophotometry. [Result] The 8 U/g exogenous α-amy-lase could improve the specific activity of the leaf α-amylase at yel owing and color-fixing stages, but could not at stem-drying stage, and similarly, the 80 U/g exoge-nous β-amylase could improved the specific activity of the leaf β-amylase at the yel owing stage and the early period of color-fixing stage. The leaf starch could be enhanced to degrade by the exogenous α- or β-amylases and the enhancing effect of the former was stronger than that of the later. 1.50 mg/ml Ca2＋ improved the specific activity of the leaf （α＋β）-amylase mainly due to its enhancing effect on the leaf α-amylase, and increased the starch degradation. 4 mmol/L Mn2＋ inhibited the leaf α-amylase from yel owing to the early period of color-fixing and the β- and （α＋β）-amylases from the yel owing to the later period of color-fixing, but enhanced the leafα-amylase from the later period of color-fixing to the later period of stem-drying and the β- and （α＋β）-amylases at the later period of stem-drying. Meanwhile, Mn2＋ ham-pered the starch degradation during yel owing, but promoted it from the early period of color-fixing to stem-drying. 1 mg/ml K＋ enhanced the leaf α-, β- and （α＋β）-amy-lases during the yel owing stage, but lowered them from the early period of color-fix-ing to the later period of stem-drying, and always inhibited the leaf starch degrada-tion. [Conclusion] The exogenous α-, β- amylases and Ca2＋ of suitable concentra-tions could be used to treat the tobacco leaves before flue-curing to improve the leaf starch degradation during the curing.

Relationship Between Hyperspectral Parameters and Physiological and Biochemical Indexes of Flue-Cured Tobacco Leaves

The experiment was set up for examining the physiological and biological indexes quickly and exactly, for obtaining information of tobacco-field fertilizing and tobacco growing. The ASD Field spec FR 2500 was used to measure spectra reflectance of flue-cured tobacco and the relationship between hyperspectral parameters and biochemical contents （total nitrogen, chlorophyll, carotenoid）, and physiological indexes （fresh weight, dry weight, moisture content） of flue-cured tobacco leaves was studied by correlation and stepwise regression statistic methods at different nitrogen and potassium levels. The results indicated that the spectra curves of different treatments had obvious rules and great diversities. There were high correlations between different types of spectra parameters and ten physiological and biochemical indexes of flue-cured tobacco leaves. Hyperspectral characteristic variables of ten physiological and biochemical indexes were found through stepwise regression, and SDr/SDb was the characteristic variable closest to seven biochemical contents. Simultaneously, the R2 and regression coefficient of equations reached 0.05 significant level and the equations had good estimating effects through the examination of other samples. Accordingly, this study suggested that the ten physiological and biochemical indexes could be estimated quickly by the estimating models, at the same time nitrogen-potassium fertilization and growth condition of flue-cured tobacco could be inspected.

Analysis of Growth Laws of Leaves of Flue-cured Tobacco in Various Periods

The growth laws of leaves of flue-cured tobacco in different positions in various periods were summarized. The results showed that the growth speed of new leaves of flue-cured tobacco increased constantly until their growth was the fastest, and then it reduced irreversibly. The length and width of leaves in each position increased fastest when they grew depending on photosynthates instead of or- ganic compounds from functional leaves. Therefore, it is concluded that the increases of leaf length, width and area, and dry matter, and the peak of photosynthetic rate appear successively during the process of leaves of flue-cured tobacco, and the leaf area correction coefficient of leaves of flue-cured tobacco is related to the shape of leaves, which are affected by leaf position and the variety of flue-cured tobacco. The study can provide scientific reference for further research on the growth laws of leaves of flue-cured tobacco.

Effects of Different Flue-curing Technologies on Microscopic Structure of Flue-cured Tobacco Leaves

[Objective] This study aimed to compare the effects of Chinese quality-improving fragrunce-increasing tobacco flue-curing technology, Chinese three- stage tobaeeo flue-curing technology and Zimbabwean tobaceo flue-euring technology on microscopie structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [ Method ] Middle leaves of tobacco cultivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process, to investigate the microscopic structure of flue-cured tobaceo leaves. [ Result] During three flue-curing processes, leaves, palisade tissues and sponge tissues shrank gradually. Three flue-euring processes exhibited significant differ- ences in the peak of tissue shrinkage ： microscopic structure of flue-cured tobacco leaves in Chinese three-stage tobacco flue-curing process shrank earliest, follower by Chinese quality-improving fragrance-increasing tobacco flue-curing process; flue-eured tobacco leaves in Zimbabwean tobacco flue-curing process presented the latest shrinkage. At 84 h post-curing, leaf thickness in three flue-curing processes showed a descend order of Chinese three-stage tobacco flue-curing process 〉 Chinese quality-improving fragrance-increasing tobacco flue-curing process 〉 Zimbabwean tobacco flue-curing process. Upper and lower epidermal cells in Zimb- abwean tobacco flue-curing process ruptured earlier than other two flue-curing processes; eventually, the majority of cells ruptured and mixed with palisade tissues and sponge tissues. In Chinese quality-improving fragranee-increasing tobacco flue-curing process, only a small number of epidermal cells in dried leaves ruptured. Among three flue-curing technologies, Zimbabwean tobacco flue-curing technology exhibited the greatest damage to epidermal cells, followed by Chinese three-stage tobaceo flue-curing technology; Chinese quality-improving fragrance-increasing tobacco flue-curing technology had the minimum damage to epidermal cells. Mese- phyll cross-section exhibited significant morphological changes in stomata. To be specific, at 0 - 12 h post-curing, stomata of tobacco leaves closed with slightly prominent stamatal apparatuses on upper and lower epidermis; at 24 -72 h post-curing, stomata of tobaceo leaves changed gradually from opening to closure with significantly prominent stomatal apparatuses on upper and lower epidermis; at 84 h post-curing, stomata of tobacco leaves closed, and the majority of stomatal appa- ratuses were significantly prominent. In Chinese quality-improving fragrance-increasing tobacco flue-curing process, only a small number of epidermal ceils ruptured at 84 h pest-flue-curing; palisade tissues and sponge tissues shrank almost simultaneously. Significant gaps were observed between palisade tissues and between pal- isade tissues and sponge tissues. Chinese quality-improving fragrance-increasing tobacco flue-curing technology exhibited lower disorder level compared with other two flue-curing technologies. [ Conclusion] Chinese quality-improving fragrance-increasing tobacco flue-curlng technology was conducive to maintaining the micro- scopic structure integrity of flue-cured tobacco leaves and obtaining high-quality flue-cured tobacco leaves.

Effects of Different Flue-curing Technologies on Submicroscopic Structure of Flue-cured Tobacco Leaves

[ Objective] This study aimed to compare the effects of low-temperature low-humidity tobacco flue-curing technology, moderate-temperature moderate- humidity tobacco flue-curing technology and moderate-temperature high-humidity tobacco flue-curing technology on submicroscopic structure of flue-cured tobacco leaves to provide theoretical basis for tobacco flue-curing. [ Method] Middle leaves of tobacco cuhivar K326 were collected in Pengshui County of Chongqing City for flue-curing experiment using three flue-curing technologies. Leaf samples were collected regularly in the flue-curing process, to investigate the submicroscopic structure of flue-cured tobacco leaves. [ Result] Morphology changes and structural rupture of chloroplasts occurred at different time during three flue-curing proces- ses. In low-temperature low-humidity flue-curing process, morphology changes and structural rupture of chloroplasts occurred late but rapidly; in moderate-tempera- ture moderate-humidity flue-curing process and moderate-temperature high-humidity flue-curing process, morphology changes and structural rupture of chloroplasts occurred early but slowly. Among these three flue-curing processes, the speed of changes in mitochondria morphology, cristae number and membrane rupture pres- ented an upward order of low-temperature low-humidity flue-curing process 〈 moderate-temperature high-humidity flue-curlng process 〈 moderate-temperature moderate-humidity flue-curing process. In low-temperature low-humldity flue-curing process, starch granules in chloroplasts ruptured after flue-curing for 36 -48 h ; in moderate-temperature moderate-humidity flue-curing process, starch granules in chloroplasts ruptured after flue-curing for 24 - 36 h; in moderate-temperature high-humidity flue-curing process, starch granules in chloroplasts ruptured after flue-curing for 12 - 24 h. [ Conclusion ] Using low-temperature low-humidity flue- curing technology could prolong the maintenance duration of the submicroscopic structure integrity of flue-cured tobacco leaves, which was conducive to fully decom- posing and transforming substances in tobacco leaves and obtaining high-quality flue-cured tobacco leaves.

Effects of Different Baking Processes on Carotenoid Content in Upper Leaves of Fluecured Tobacco

[Objective] We aimed to improve the quality of flue-cured tobacco with K326 upper leaves and explore the optimal tobacco baking process in Chongqing tobacco-producing region. [Method] Four different baking processes （endogenetic force moisture-removing flue-curing technique, exogenetic force moisture-removing flue-curing technique, three-stage flue-curing process, three-stage and six-step flue- curing process） were adopted in this research to investigate the effects of different baking processes on carotenoid content of same-maturity degree upper leaves of the flue-cured tobacco K326. [Result] The results showed at the yellowing and color fixing stages, the carotenoids were most fully decomposed in endogenetic force moisture-removing flue-curing technique. The decomposed carotenoid content was lowest in exogenetic force moisture-removing flue-curing technique, for which the carotenoid content was highest （50.53 mg/g）. [Conclusion] At the yellowing and color fixing stages, exogenetic force moisture-removing flue-curing technique was most conducive to the carotenoid accumulation in tobacco baking process.

Correlations between Quality Index and Content of Cellulose and Lignin in Upper Leaves of Fluecured Tobacco in Wulin Mountain Area

In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountain area in 2011 and 2012 were used as test materials to measure the contents of cellulose and lignin in tobacco leaves and analyze the differences among varieties and between years. Meanwhile, correlations among contents of cellulose and lignin and appearance quality, physical characteristics, general chemical components and indexes of senso- ry quality were studied. The results showed that the contents of cellulose and lignin had no significant difference among years and varieties. Cellulose content was sig- nificantly correlated with some indexes of appearance qualities, physical indexes, general chemical compositions and sensory qualities. Lignin content was significantly correlated with grayness and oil content but not other quality indexes of tobacco leaf. It could be seen that the differences of cellulose and lignin contents between different years and among varieties were not significant. Cellulose content was closely correlated with quality indexes of tobacco leaf while lignin content had a small effect on tobacco leaf quality.

The Quality Difference of Tobacco Leaves Between Different Flue-curing Processes in Honghe Tobacco-growing Area

[Objectives] This study was conducted to compare the effects of different curing processes,in order to optimize the local supporting intensive fluecuring process.[Methods] A comparative experiment was carried out in Mile,Luxi and Jianshui on the four-layer tobacco-packed intensive curing process(K1)and the eight-point precise and intensive curing process(K2).[Results]The results showed that according to the appearance evaluation of the tobacco leaves,K1 was higher than K2 in respective scores of color,maturity,leaf structure and defects and the total score,while K1 equaled K2 in the scores of identity,oil content,chroma and length.The differences in respective scores of the two processes were not significant.According to the results of sensory evaluation,the two tobacco enterprises got different evaluation results of unblended cigarettes made of the middle leaves due to different raw material requirements of the enterprises by different processes.K1 was higher than K2 in the sensory evaluation of China Tobacco Yunnan Industrial Co.,Ltd.,while it was lower than K2 in that of China Tobacco Zhejiang Industrial Co.,Ltd.,and the difference in the total score between the two processes was significant.From the content of chemical components,in the conventional chemical component contents including total sugar,reducing sugar,chlorine and starch,K1 was higher than K2,while in the contents of potassium,total phytonine,total nitrogen and petroleum ether extract,K1 was lower than K2,but the differences were not significant.K1 was lower than K2 in the contents of neutral aroma components including ketones,alcohols,aldehydes,heterocyclics,neophytadiene and total content,while K1 was higher than K2 in the contents of esters,phenols,but the respective differences were not significant.Except the significant difference in the total score in the sensory evaluation of China Tobacco Zhejiang Industrial Co.,Ltd.,there were no significant differences in other items in the appearance evaluation,sensory evaluation and chemical composition of tobacco leaves between K1 and K2.[Conclusions] The supporting intensive curing process can be further optimized on the basis of this study.

Climatic Characteristics of Hubei Tobacco Area and Its Influence on the Quality of Upper Leaves

In order to provide a more suitable environment for tobacco leaf growth, this study collected meteorological information and tobacco leaf quality information from the main tobacco-producing counties in the province and conducted relevant analysis to find out the main meteorological factors affecting the growth, development, yield, and quality of upper tobacco leaves. Clarify the suitable climatic conditions for the growth and development of the upper leaves, and clarify the influence of various meteorological factors on the quality of the upper leaves. The results showed that the nicotine and total nitrogen content of the upper leaves were significantly positively correlated with the average daily temperature during the maturity period, and negatively correlated with the rainfall during the maturity period;the rainfall in July was significantly positively correlated with the upper leaf clutter score, which was sufficient in the mature period. Moisture conditions are conducive to alleviating the upper leaf clutter;the number of sunshine hours in August is the main factor affecting the content of aroma substances in the upper leaves, and it is also significantly positively correlated with the content of aroma substances.

Differences of Physiological and Biochemical Indexes of Upper Fresh Leaves and Post-growth Roots in Different Quality Stages

In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde （MDA）, superoxide dismutase （SOD） activity, chlorophyllase activity, amylase activity, medium trace element content, chemical component content, root fresh weight, dry weight and activity in the normal tobacco leaves, tobacco leaves rich in nutrients and premature grey tobacco leaves were studied. The results showed that compared with the normal tobacco leaves, the root fresh weight, dry weight and activity in the premature grey tobacco leaves decreased by 41.22%, 14.44% and 60.29% respectively, while malonaldehyde content increased by 34.82%, and chlorophyllase, α-amylase, β-amylase and SOD activity declined by 89.55%, 65.71%, 71.26% and 37.25% respectively. Chlorophyllase, co-amylase and 13-amylase activity in the tobacco leaves rich in nutrients decreased by 58.76%, 36.19% and 41.93% respectively. The content of medium trace elements in the tobacco leaves rich in nutrients and premature grey tobacco leaves was lower than that of the normal tobacco leaves. Starch, total sugar, reducing sugar and potassium content in the normal tobacco leaves were higher than that of the tobacco leaves rich in nutrients and premature grey tobacco leaves.

Analysis of the Appearance Quality of Tobacco Leaves in the Tobacco-growing Areas of Qujing City

In order to set up the digitization indices system of appearance quality of flue-cured tobacco leaves in Qujing. According to the relevant standards,the quantitative analysis on appearance quality of 39 cutter and upper tobacco leaf samples which were collected from eight fluecured tobacco production regions of Qujing City,Yunnan Province were carried out in 2011,respectively. The results showed that the difference in evaluation score of appearance quality of flue-cured tobacco in eight regions was not significant. The tobacco leaves had high maturity,high oil content,loose structure and good appearance quality. The scores of appearance quality of flue-cured tobacco in Shizong County and Malong County are higher than other regions. The two regions are suitable for tobacco plantation. The preliminary digitization indices provide reference and guidance to tobacco production and standards system of tobacco leaves base.

施氮量对云烟121上部烟叶代谢及品质的影响

为提高烤烟上部叶品质与可用性,筛选出曲靖烟区云烟121适宜的施氮量,分别施用纯氮82.5、105.0和127.5 kg·hm^(-2)进行大田试验,测定不同处理的农艺性状、上部成熟鲜烟叶的超微结构及烘烤后的外观质量、化学成分、感官质量等指标,并进行代谢组学分析,综合评价不同施氮量处理下云烟121的生长情况与上部烟叶品质。结果表明,3个施氮量处理烟株的长势无明显差异,其中105.0 kg·hm^(-2)处理烟株的综合发病率最低。随着施氮量的增加,云烟121上部叶片中的叶绿体降解减缓,淀粉粒与嗜锇颗粒体积增大,其中105.0 kg·hm^(-2)处理烟叶的嗜锇颗粒数量最多。施氮水平影响云烟121上部叶的代谢模式,且主要集中在莽草酸和苯丙烷代谢途径。在105.0 kg·hm^(-2)处理下,云烟121上部叶烤后的外观质量、化学成分、感官质量、经济性状均优于其他施氮水平。由此表明,施用纯氮105.0 kg·hm^(-2)能够有效提高曲靖烟区云烟121上部叶的品质与可用性。

主成分分析法在山东上部烟质量评价中的应用

本研究旨在运用主成分分析法对山东地区上部烟叶的质量进行综合评价,以便为该地区烤烟质量的准确评估提供科学依据。研究以山东10个主要植烟县2020年和2021年间105份B2F等级烟叶样品为材料,通过应用标准化法和主成分分析法对这些烟叶样品的物理特性和化学成分指标进行归类处理,并对各植烟县样品的上部烟叶质量进行分类。研究发现,单叶重与叶长和叶宽、叶片密度与叶片厚度、总糖与还原糖、烟碱与氮间极显著正相关,且主成分特征向量一致,可分别归为一类指标。根据物理特性评价结果,可将山东产区上部烟分为三类,根据化学成分评价结果,可将山东产区上部烟分为两类。综合考虑物理特性和化学成分评价结果,山东产区上部烟叶可分为四类。其中沂源、五莲、临朐为一类,兰陵、沂水、莒县、莱芜为一类,淄川、黄岛为一类,诸城则单独构成一类。

不同润叶和复烤强度对上部烟叶质量的影响

以云烟87上部烟叶为研究对象,以颜色深浅度、色度、均匀度、油分、常规化学成分和感官质量为评价指标,开展了不同润叶和复烤强度对上部烟叶质量的影响研究。结果表明,随着润叶强度的增加,润叶后烟叶颜色逐渐加深,色度偏向深橘黄,均匀度逐渐变差,油分增加;复烤后烟叶颜色变浅,色度向柠檬黄转变,均匀度提升,油分降低,较高温度复烤的烟叶均匀度和油分优于低温复烤;随润叶强度增加烟叶烟碱和总糖含量逐渐升高,复烤后其含量逐渐下降;随润叶强度增加润叶后的感官质量逐渐降低,低水分润叶下随复烤温度增加感官质量提升,高水分润叶下随复烤温度增加感官质量下降。综合来看,低水分润叶(W15%)和较高温度复烤(T 70℃)更有利于上部烟叶质量的形成。

不同氯化钾施用措施对烤烟上部叶产质量的影响

[目的]探讨适宜泸州烟区的氯化钾施用措施,进一步完善田间上部烟叶的调控技术。[方法]采用田间试验,以“中川208”为试材,设施氯量30、60、90、0 kg/hm^(2)4个水平,基追比为5∶5,追施时期设移栽后30和50 d,共7个氯化钾施用处理。分析上部烟叶农艺性状、SPAD值、经济性状、化学成分、物理性状的变化。[结果]较不施用氯化钾而言,施用氯化钾使上部烟叶产量、产值、均价、中上等烟比例分别提高3.11%~9.17%、6.12%~19.29%、2.79%~12.92%、4.01%~18.25%;烤后烟叶颜色、成熟度、身份、油分、色度均得到提升,综合得分提升1.15%~8.30%。[结论]以基肥施用氯化钾30 kg/hm^(2),移栽50 d后追施30 kg/hm^(2)的施肥措施经济效益最高,烤后上部烟叶外观质量、化学成分、物理性状评分最高。

烤烟品种K326上部叶烤后单叶重与感官质量的关系

为探索张家界市上部烟适宜的单叶重,以主栽品种K326为研究对象,设置不同单叶重区间,分析了单叶重与烟叶主要物理特性及感官质量的关系,确定了适宜的单叶重。结果表明:综合各单叶重对烟叶物理性状、感官质量的影响可知,高峰试验点单叶重为8~10、>10~12、>12~14 g时均表现较优,江垭试验点单叶重为8~10、>10~12 g时上部叶质量较好,可用性较高。根据叶长与单叶重的相关性,得出张家界烟区适宜的叶长区间:高峰试验点可将上部叶叶长在51.25~67.82 cm的占比、江垭试验点可将上部叶叶长在51.21~63.13 cm的占比作为技术调控目标。