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.

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 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.

Detection and Quantitative Analysis of Dominant Bacteria On Aging Flue-cured Tobacco Leaves

[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.

Yield and Nicotine Content of Flue-Cured Tobacco as Affected by Soil Nitrogen Mineralization

Nitrogen(N)supply is the most important factor affecting yield and quality of flue-cured tobacco(FCT).A field experiment and an in situ incubation method were used to study the effects of soil N mineralization in the later stages of growth on yield and nicotine content of FCT in Fenggang and Jinsha,Guizhou Province.The yield and market value of FCT at Fenggang were much lower than those at Jinsha.However,the nicotine content of middle and upper leaves was much higher at Fenggang than at Jinsha when the same rate of fertilizer N was applied,which might be due to a higher N supply capacity at the Fenggang site.At later stages of growth(7-16 weeks after transplanting),the soil net N mineralization at Fenggang(56 kg N ha^(-1))was almost double that at Jinsha(30 kg N ha^(-1)).While soil NH_4-N and NO_3-N were almost exhausted by the plants or leached 5 weeks after transplanting,the N taken up at the later growth stages at Fenggang were mainly derived from soil N mineralization,which contributed to a high nicotine content in the upper leaves.The order of soil N contribution to N buildup in different leaves was:upper leaves>middle leaves>lower leaves.Thus,soil N mineralization at late growth stages was an important factor affecting N accumulation and therefore the nicotine content in the upper leaves.

Comparative Analysis on Chemical Components and Sensory Quality of Aging Flue-Cured Tobacco from Four Main Tobacco Areas of China

Complicated changes are happening during the aging process of flue-cured tobacco （FCT） and understanding of the changing components is of great significance in improving the quality,shortening aging time,and enhancing production and economic efficiency in tobacco industry.The aging samples of FCT from four main producing areas of China,i.e.,Yunnan,Sichuan,Hubei,and Dongbei,were used to study the changing rule of the components such as alkali,acid,and carbohydrate as well as the aroma and their relationship with sensory quality;and based on the correlation among the components and the sensory quality index,multivariable models were established to predict the aging quality.The results showed that the sensory quality of FCT increased steadily during the aging time,and at the same time,the acidic components （total organic acids,volatile acids） increased gradually,while the alkaline substances （nicotine,volatile alkali）,carbohydrate （total sugars,reducing sugar） and pH values showed a downward trend.Correlation analysis found that the sensory quality and pH values were negatively correlated （P0.05）,while the sensory quality with total organic acids and aroma were positively correlated.The optimal model for predicting the quality of FCT was y=56.75-0.63x12＋50.09x2-13.27x22,（y：sensory quality;x1：pH;x2：total organic acids）.The average predicating error was 1.04% with maximum predicating error of 2.89% and the accuracy rate of above 97%.

Proteomics Identification of Differentially Expressed Proteins Relevant for Nicotine Synthesis in Flue-Cured Tobacco Roots Before and After Decapitation

Nicotine is a secondary substance synthesized in tobacco roots. In flue-cured tobacco planting, tobacco decapitation is an effective practice to promote nicotine biosynthesis by regulation of the redistribution of total nitrogen amounts. However, proteins relevant to nicotine synthesis in tobacco roots has not been identified and characterized yet. It is important to explore the regulation of nicotine biosynthesis in tobacco roots. To identify the proteins relevant to nicotine synthesis, the protein patterns in roots of flue-cured tobacco （cv. K326） before and after decapitation were analyzed. In the present study, the protein patterns in roots of flue-cured tobacco were analyzed by two-dimensional electrophoresis （2-DE）, and the differentially-expressed spots were identified by matrix assisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS）. Paired comparison of 2-DE maps revealed 26 spots of differentially-expressed proteins in roots before and after decapitation. Furthermore, nine differentially-expressed spots were identified. There were four proteins which were enzymes possibly involved in nicotine biosynthesis. In addition, the roles of the four enzymes in nicotine biosynthesis were discussed in a putative network. Our results would contribute to the understanding of the regulation pathway of nicotine biosynthesis and further to the molecular manipulation on the nicotine contents in flue-cured tobacco.

Effect of Combined Application of Organic Fertilizer and Chemical Fertilizer in Different Ratios on Growth,Yield and Quality of Fluecured Tobacco

The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were analyzed by using variance analysis,significance test and other methods.The release efficiency of organic fertilizer in the soil was slower,and the effect of organic fertilizer on the growth of tobacco plants was worse than that of chemical fertilizers,and under 25% organic fertilizer + 75% chemical fertilizer treatment,the quality of the fluecured tobacco was good.Under the treatment of 50% organic fertilizer + 50% chemical fertilizer,the production of flue-cured tobacco was high and the ratio of first-class tobacco was high.It is suggested that the organic fertilizer application ratio should be 25%-50% in the agricultural production.

Characteristics of Potassium-Enriched, Flue-Cured Tobacco Genotype in Potassium Absorption, Accumulation, and In-Ward Potassium Currents of Root Cortex

This study was to investigate the main traits of potassium-enriched, flue-cured tobacco genotypes related to potassium absorption, accumulation, and in-ward potassium currents of the root cortex. Hydroponic methods, K^＋-depletion methods, and patch-clamp, whole-cell recordings were conducted to study the accumulation of dry matter and potassium in different organs, and to measure potassium absorption and dynamic and in-ward potassium currents in potassium-enriched, fluecured tobacco genotypes. The average dry weights of leaves and whole plant of potassium-enriched, flue-cured tobacco genotype ND202 were 10.20, and 14.85 g, respectively, higher than JYH （8.50 and 13.11 g, respectively） and NC2326 （8.39 and 12.72 g, respectively）, when potassium concentration in the solution ranged from 0.1 to 50 mmol L^-1. Potassium accumulation in the leaves of ND202 was 18.6% higher than JYH and 34% higher than NC2326 when potassium concentration in the solution was superior to 0.5 mmol L^-1. The Vmax （the maximum velocity） of ND202 was 118.11 lamol FW g^-1 h^-1, obviously higher than that of JYH （58.87 μmol FW g^-1 h^-1） and NC2326 （64.40 μmol FW g^-1 h^-1）. In the in-ward potassium currents, the absolute value of current density （pA/pF） of ND202 was 60, higher than that of JYH （50） and NC2326 （40）. Potassium concentration in leaves, Vmax, and in-ward potassium currents, could be used to screen potassium-enriched, flue-cured tobacco genotypes.

Changes of Polyphenols in Tobacco Leaves During the Flue-Curing Process and Correlation Analysis on Some Chemical Components

The changes of polyphenols in tobacco leaves during the flue-curing process and correlation analysis on some chemical components were studied. Leaf samples were taken from different tobacco-producing regions in Henan Province, China. The results indicated that the content of total phenols increased during the first 24 h of curing, and then decreased. It reached the lowest value at 72 h of curing and increased rapidly after that. The content of chlorogenic acid also increased during 0-24 h of curing. But the lowest point occurred at 60 or 72 h of curing and then it increased till the end of the curing process. The content of mtin generally increased with curing, and showed little fluctuations. The changes of PPO and POD activity were the opposite. Rutin was found to have a highly significant positive correlation with total sugar （r=0.822^＊＊）, but a highly significant negative correlation with starch, nicotine, and protein.

Effect of Fertilizer N Forms on Physiological Metabolism and Potassium Uptake of Flue-Cured Tobacco

The growth, chlorophyll composition, photosynthesis, respiration, K uptake and root K+ secretion offlue-cured tobacco as thected by different concentrations of N supplied as urea, NaNO3 and NH4NO3 werestudied under the experimental condition of sand culture. The results showed that the content of K in thefiue-cured tobacco was not merely related with root vitality and uptake but also closely related with root cellmembrane structure and K+ secretion.

Risk Regionalization of Drought for Flue-cured Tobacco Planting in Qujing City Based on GIS

The risk regionalization of drought for flue-cured tobacco planting in Qujing City was studied to provide reference for drawing on advantages and avoiding disadvantages in flue-cured tobacco planting,disaster reduction,and disaster relief services.According to the production practice of flue-cured tobacco and local climate analysis,the risk of disaster-causing factors,sensitivity of disaster-breeding environment,vulnerability of carriers,and disaster prevention and reduction capability were analyzed and evaluated quantitatively.Secondly,starting from the formation mechanism of drought,a risk assessment model of the meteorological disaster was established by GIS technology.Finally,the risk assessment and regionalization of drought in the critical periods for drought-stricken flue-cured tobacco (transplanting period,root extending stage and vigorous growth period) in Qujing City were carried out.The results showed that in Qujing City,the risk areas of drought for flue-cured tobacco planting were divided into five grades in the transplanting period and six grades in the root extending stage and vigorous growth period.

Effect of Different Intercropping Methods on the Reduction of Heavy Metal Content in Flue-Cured Tobacco

Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue-cured tobacco,the content of four kinds of heavy metals in soil and tobacco leaves in different intercropping treatments was tested. The results showed that there were significant differences between the effects of intercropping on the content of some heavy metals in soil and tobacco leaves. Different interplanting methods had a positive effect on the reduction of heavy metal content in tobacco leaves and play a very important and positive role in actual production.

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.

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.

Effects of Amount of Green Manure Returned to Field on Yield and Quality of Flue-cured Tobacco

The effects of amount of green manure returned to field on yield and quality of flue-cured tobacco were studied by field experiment. The results showed that significant positive correlation existed between tobacco leaf yield and small or moderate amount of green manure returned to field. Path analysis showed that moderate amount of green manure returned to field affected yield and quality of tobacco leaves, small green manure returned to field mainly affected leaf yield, while large amount of green manure returned to field mainly affected leaf quality. Therefore, the effect of moderate amount of green manure returned to field on yield and quality of tobacco leaves was best, and moderate amount of green manure returned to field was recommended in production of flue-cured tobacco.

Screening of Low Tar Flue Cured Tobacco Varieties

The main agronomic traits,economic traits,appearance quality,main chemical components,gas composition and physical parameters of 10 flue cured tobacco varieties were investigated in the experiment.And the field natural incidence of the main diseases was investigated.The results showed that main agronomic characters of the 10 varieties were in line with the breeding objectives,among which 5 varieties have good economic characters;5 varieties have good appearance quality;6 varieties have coordinated chemical composition and high potassium content;9 varieties have good smoke components and physical indicators.

Application of Tobacco Leaves from Shandong in " Taishan" Brand

In view of the fact that the proportion of tobacco leaves from Shandong in the stocks of a company is large,based on the premise of not affecting the quality of cigarettes,through the scientific evaluation,selection and matching test,the proportion of tobacco leaves from Shandong in the formula of " Taishan" cigarette A has been increased,and the sensory quality of " Taishan" cigarette A before and after the test is basically stable.Moreover,the stocks of tobacco leaves from Shandong can be decreased in time.