Correlation analysis between main chemical constituents of tobacco leaves and endogenous harmful components in mainstream cigarette smoke was conducted. Leaf stalk positions exhibited a high relation with endogenous harmful components and hazard index (H). Upper stalk position leaves had greater release of 1-butanone,4-(methylnitrosoamino)-1-(3-pyridinyl)-(NNK), B[a]P, HCN, NH3 and phenol in mainstream cigarette smoke, and a higher hazard index than middle position leaves except for crotonaldehyde, which had greater release from middle position leaves. Different endogenous harmful components in mainstream cigarette smoke presented complicated correlation with main chemical constituents in tobacco. The same type of leaf chemical constituents presented different correlations with various endogenous harmful components in mainstream cigarette smoke. Cigarette hazard index showed significantly positive correlations with contents of nicotine, protein, total nitrogen, major polyphenols and organic acids, while significantly negative correlation with potassium and carbonaceous substances, such as total sugars, reducing sugars and starch. The results suggested that properly increasing potassium content and decreasing nitrogenous constituents in cured tobacco leaf may reduce the cigarette hazard index.

To accomplish the target of“reducing the labor and cost, improving the quality and efficiency”in tobacco production, field experiments of flue-cured tobacco transplanting with plastic film marked on hole spacing (T-FMHS) were carried out in 9 of flue-cured tobacco production regions in 2012, by using the hole spacing by marked rope as control (T-RMHS). The results showed that, compared with T-RMHS, the T-FMHS with high degree of standardization, could effectively ensure the transplanting density of 16 500 plants/ha;The labor cost was reduced by 50%, and the tobacco transplanting time was shortened largely. Average yield and income increased by 25.2 kg/ha and 641 yuan/ha, respectively. Those results suggest that, by use of Plastic Film Marked on Hole Spacing in flue-cured tobacco transplanting, the standardization degree of tobacco transplanting and farmer income can increase significantly. This technology will be extended to all of the tobacco production regions in Guizhou province in 2013.

As a specific system theory, the method of Unified management combined with independent treatments(UMCWIT) is a concentrative reflection of materialistic view. Modern tobacco agriculture construction is a system project without unified path and method. The uniform of efficiency and fair, efficiency and quality, and efficiency and normalization, need to resort to the UMCWIT thinking method. The connotation and applications of the UMCWIT thinking method in modern tobacco agriculture construction were introduced, and its application principles were discussed.

Overcoming disadvantages, such as scattered production resources, poor physical geography condition, scarce facilities and equipment, and insufficient technique of tobacco grower, and creating conditions for intensive management, is crucial to the development of modern tobacco agriculture in mountainous areas. In view of that, Guizhou Provincial Tobacco Company innovated a pearl necklace model for development of modern tobacco agriculture in mountainous areas, taking small connecting lands as pearls and tractor-ploughing road as chain for planting distribution. Similarly, taking group facilities as pearls and generalized preferential service as chain for equipment configuration, and taking household operation as pearl and unified service as chain for production organization, and likewise classified innovation as pearl and standard enforcement as chain for technique application, one station and four lines as pearl and information management as chain for basic management, tobacco management as pearl and support through subsidies as chain for district development. The model takes consideration of both pursuit of scale efficiency and actual practice to create an efficient path of modern tobacco agriculture development in mountainous areas.

[目的]分析生态条件和种质因素对烤烟次生代谢产物含量的影响,为低危害烟叶生产提供理论依据.[方法]从贵州道真县、威宁县、盘县和天柱县采集K326、云烟87和贵烟1号3个烟草品种的C3F和B2F等级烟叶初烤样品,测定不同烟叶样本有机酸类、生物碱、多酚类、甾醇类物质等主要次生代谢产物含量,分析烤烟次生代谢产物含量的品种和地区差异性.[结果]同一地区3个品种(系)间的有机酸和生物碱含量差异不显著;道真县和盘县不同品种间烟叶多酚类物质含量、威宁县和盘县不同品种间烟叶甾醇类物质含量的差异均不显著;威宁县、天柱县不同品种间烟叶多酚类物质含量和道真县、天柱县不同品种间烟叶甾醇类物质含量的差异达显著或极显著水平.不同地区不同品种烟叶间的有机酸、生物碱、多酚和甾醇类物质含量差异明显,地区间烟叶主要次生代谢产物总含量的差别明显大于品种间.[结论]生态条件对烟叶次生代谢产物含量影响明显,种质因素对烟叶次生代谢产物含量影响较小.

The production status of characteristic flue-cured tobacco leaves in Central Guizhou Province during the recent years was summarized from the quality,scent style,market competitiveness,and production benefits of Mountainous Bouchet Sweet-type tobacco,and the future characteristic tobacco leaves should be developed from the special interpretation of tobacco leaves,the breeding of special variety,tobacco quality safety and the construction and perfecting of the technical support system for characteristic tobacco leaves.

The application effect of the floating raising tobacco seedling technique from 1997 to 2011 was summarized to popularize the floating raising tobacco seedling technique in tobacco production in Guizhou.The achievements,patents,system,management mode,technological standard and management standard of the floating raising tobacco seedling technique were reviewed.The authors proposed the countermeasures to further promote application of the floating raising tobacco seedling technique in tobacco production based on analyzing the problems in Guizhou.

TMV resistance of a K326 mutant was investigated by field experiment in 2006～2008.Results showed that TMV incidence after 7 days inoculation in K326, CQY,and Coker176 was 99.10%,42.54%,and 1.18%,respectively.TMV incidence in CQY and Coker176 on day14 and 21 was slightly higher than that at day7,and that of K326 was 100%.Significant difference(P0.01) in incidence was found among K326,CQY,and Coker176.In inoculation position,CQY without mosaic symptom caused necrotic spots witch were similar to those of Coker176.Disease index of CQY increased from 10.64 to 35.11 at the initial stage(7-14),and was 39.63 on day 21.Significant differences(P0.01) were found in disease index among K326,CQY,and Coker176,on day 7,14,and 21.It indicated that agronomic traits including plant height,number of leaves,stem girth,and node distance had no significant differences between K326 and CQY.Leaf of CQY was significantly shorter and wider than that of K326.Results of multiple comparison showed no significant(P0.05) difference in yield and production value between K326 and CQY.

为研究重金属对烟叶铜锌超氧化物歧化酶的作用规律,消除活体烟叶中其它因素的影响,本试验采用离体方法,利用硫酸铵盐析分级分离、乙醇-氯仿沉淀除杂、丙酮再沉淀分级得到只含铜锌超氧化物歧化酶的酶液。研究了不同浓度的Fe2+、Mn2+、Se2+、Sb2+、Cd2+对该酶的影响。结果显示:在浓度为0～100mg/L范围内,Fe2+、Mn2+、Sb2+、Cd2+都能使铜锌超氧化物歧化酶的活性先降低后升高,但在相同浓度下,Cd2+对酶活性的影响最大,其次是Mn2+、Fe2+。Sb2+使该酶的活性的变化趋势与Cd2+、Mn2+基本一致,仅变化幅度不及Cd2+、Mn2+显著。Se2+能降低该酶的活性,当浓度为10mg/L时,酶活性的降低率为58.78%。当Se2+浓度为20mg/L时,酶活性几乎完全丧失。分析了铜锌超氧化物歧化酶活性受Fe2+、Mn2+等影响的可能机制,以期为烟草重金属污染的酶学指标监测系统的建立提供数据支持。

MYB-bHLH-WD40 protein complex plays a crucial role in regulating the trichome differentiation in the tobacco(Nicotiana tabacum).By using RT-PCR method,a WDR(NtWDR) gene was isolated from common tobacco Yuyan 85 and the gene accession number is GQ260131.NtWDR cDNA is 1 433 bp in length with a 1 029 bp open reading frame(ORF) as well as a 147 bp 5'-untranslated region(UTR) and a 257 bp 3'-UTR.The encoded NtWDR protein is 342 aa with a calculated molecular weight(Mw) of 38.49 kDa and a isoelectric point(pI) value of 4.81.BLASTs and NCBI conserved domain search indicated that NtWDR was AN11/TTG1-type WD40 proteins.Phylogenetics analysis and structural characterizations identified NtWDR to be orthologs of PhAN11 and Le113964R.

Yunyan 85,a flue-cured tobacco variety,was planted under 1482 plants/667m2 density and applying organic manure in 5 typical ecological areas to study flue-cured tobacco quality and aroma components of different ecological areas for excavating the ecological advantage of flue-cured tobacco in Guizhou.The results showed that the flue-cured tobacco yield,single leaf weight,unit leaf area weight of Yunyan 85 planted under 1482 plants/667m2 density and applying organic manure in 5 typical ecological areas were all lower than those planted under the conventional cultivation pattern,the nicotine content of flue-cured tobacco applied with organic manure was relatively lower,its sugar content was relatively high and other quality indexes of flue-cured tobacco slightly decreased compared with those under the conventional cultivation pattern.In general,the flue-cured tobacco leaf has the characteristics of good harmoniousness,high sugar/nicotine ratio,elegant gas,intensified pleasure,abundant aroma and obvious sweet.There is obvious difference in aroma components among 5 different ecological areas,which reflects regional characteristics.

The superoxide dismutase in tobacco leaves played a vital role in anti-oxidation.In order to eliminate various environmental factors,the in vitro method was applied in the present investigation to study changing trends of the copper-zinc superoxide dismutase activity caused by rare earth ions.The enzyme solution of copper-zinc superoxide dismutase from tobacco leaves was obtained by using ammonium sulphate to form different levels of precipitates and by using chloroform and alcohol to isolate the impurities and acetone for further clean-up.The effects of La3+,Sm3+,Y3+ and Ce3+ with different concen-trations on copper-zinc superoxide dismutase were studied.The results showed that the activity of copper-zinc superoxide dismutase demonstrated a decreasing trend first,then an increasing trend and finally a decreasing trend in response to the increasing La3+,Sm3+,Y3+ or Ce3+ supply from 0 to 250 mg / L.At the same concentration,however,the change of copper-zinc superoxide dismutase activity under the influence of Y3+ was strongest,and then the Sm3+.The changes in the enzyme activity under the effects of these four rare earth ions were approximately 20%,and the ability of eliminating.O2-varied considerably.

In order to understand the effects of different cropping system on accumulation of soil nitrate-N and tobacco nitride,distribution of the nitrate-N on soil profile,total nitrogen,nicotine and protein in the tobacco leaf were studied in the plots with 20 years' continuous mono-cropping of corn and flue-cured tobacco based on different nitrogen level.The results show that nitrite-N in the soil profile decreases gradually with increase of soil layer depth.The nitrate-N from 0 to 100 cm soil layer is higher than that of corn in long-term continuous mono-cropping tobacco.The soil nitrate-N increases obviously with raise of soil temperature during flue-cured tobacco growth,and is enriched in 20 cm to 40 cm soil layer when higher nitrogen used in single season.Mono-cropping tobacco also leads to a great accumulation of soil nitrate-N,but the rate of soil N declines sharply,and the total N,nicotine and protein in the leaf and tobacco production also decline gradually.It is very important for reducing nitrate-N and improving tobacco performance to optimize cropping system and scientific fertilizations

The influence of continuous flue-cured tobacco cropping(0~4 years) on the microelement content in tobacco-planting soil and tobacco plant was studied through pot experiment.The results showed that along with the increase of tobacco-planting years,the content of exchangeable calcium,exchangeable magnesium,available Cu and available Zn in the soil presented the trend from increasing to reduction,continuous cropping did not lead to the imbalance of the proportion of exchangeable calcium to exchangeable magnesium in the soil.The content of available Mn and available Fe in the soil increased gradually when the tobacco-planting years increased.Since the first season of continuous cropping,Mn and Cd in tobacco plant were continuously enriched.The activity of endogenous protective enzymes(SOD and POD) which could resist the poison of active oxygen in the leaf of flue-cured tobacco changed from increasing to reduction.Excessive accumulation of Mn and Cd in tobacco plant as well as Cd in the soil might lead to continuous cropping obstacle.

Using large waterproof installations to regulate different soil water contents strictly, we studied effects of spring drought, summer drought and sustained mild drought on the activity of cell defense enzymes in flue-cured tobacco leaves. The results indicated that the superoxide dismutase (SOD) activity increased first and then declined under all kinds of drought stress, the activity of peroxdase (POD) and catalase (CAT) showed a trend of increasing-declining-increasing under spring drought and sustained mild drought, while increasing first and then declining under summer drought. The activity of cell defense enzymes was most affected by summer drought during three treatments.

The effects of soil moisture on growth,yield and quality of flue-cured tobacco were studied under artificial irrigation conditions.The results showed that the soil moisture content with 60% at root extending stage,80% at faster growing stage and 70% at maturing stage were the best for the growth,yield and quality of tobacco.161 kg water was required for each plant to keep the soil water content from 60% to 80% and 70%.Appropriate water consumption at the root extending stage,vigorous growing stage and maturing stage were 19.3%,38.5% and 42.2% respectively.

The different insertional position of kaipianjiangjianling was tested to investigate the effect on tobacco yield and quality for improving upper tobacco quality and raising farmers' income.The results show that kaipianjiangjianling can significantly increase tobacco yield and output value by raising the tobacco length and width obviously and there is no significant difference between different treatments.The nicotin content of treatment 1, 2 and 3 decreases 17.92%,15.28% and 12.26%,the reduction sugar content increases 160.15%,129.21% and 20.54%,the leaf weight and thickness decreases 7.6%,9.8% and 13.68%,and 25.8 μm,25.1 μm and 26.2 μm,the balance water content increases 9.28%,7.86% and 3.31%,the free burning time of treatment 1,2 and 3 shortens 2.43 s,3.02 s and 0.1 s compared with CK respectively.

The pot and field plot experiments were conducted to study the effects of 9 fungicides on controlling tobacco leaf spot.The results from the field plot test showed that the controlling effect of carbendazim,mancozeb,thiophanate-methyl thiram,chlorothalonil and thiophanate-methyl was 84.3%,83.8%,81.6%,68.5% and 31.2% respectively.Because carbendaxim with sulphur powder can not be appied at the picking stage,mancozeb should be selected in tobacco production for controlling tobacco leaf spot.

[Objective]The research aimed to study the effect of different drought stress on the contents of proline and soluble protein. [Method] The contents of proline and soluble protein of tobacco K326 under four kinds of intensity of drought stress were studied.[Result] With time of drought-stress increasing, the proline content kept increasing, which was positively correlated with the intensity of drought stress.The soluble protein content reduced after increasing first, and the lowed range was related with the intensity of drought stress.[Conclusion] Continuous drought stress had the most influential effect on the contents of proline and soluble protein, and the summer drought was inferior to it.

Effects of different levels of fertilization and microorganisms on the growth of continuous cropping tobacco seedlings were studied.The results showed that the microbial community in the soil after one year's tobacco planting was the most suitable for the growth of tobacco,but the inhibition of soil microorganisms to tobacco increased along with the increase of continuous cropping years.Soil microorganisms inoculated by axenic water had certain effect on tobacco growth.Fertilization had certain promotive effect on the growth of tobacco.