贵州喀斯特山区烟叶高光谱参数与叶绿素含量的关系

为实时无损快速地检测烟叶叶绿素含量(质量分数),利用Field Spec 3便携式地物光谱仪采集了贵州喀斯特山区主栽品种南江3号不同长势无病虫害烤烟叶片光谱,测定了相应烟叶的叶绿素含量;同时利用光谱分析技术提取光谱特征变量,并分析了烤烟叶片叶绿素含量与原始光谱、光谱一阶微分以及高光谱特征变量间的相关性;采用多元逐步回归及光谱特征单变量建立了叶绿素含量估测模型并进行了模型精度检验。结果表明:叶绿素a(Chl a)、叶绿素b(Chl b)与原始光谱反射率的相关系数分别在700和701 nm波长处最大;与光谱一阶微分的相关系数分别在623和653 nm波长处最大;Chl a与高光谱特征变量λg,Chl b与高光谱特征变量SDr/SDb的相关系数最大。基于光谱反射率一阶微分的逐步回归模型对烟草叶片Chl a和Chl b含量的估测精度较高,估测效果好。     

采后小白菜叶绿体色素含量变化及其叶绿素降解动力学的研究

目的 探究采后小白菜贮藏过程中叶绿体色素的代谢变化及其叶绿素降解的动力学模型。方法 以采后“上海青”小白菜为试材, 分别将其贮藏于室温(20 ℃)、低温(2 ℃)及冰温(-0.5 ℃)条件下, 研究其总叶绿素、叶绿素a、叶绿素b、β-胡萝卜素及叶黄素的代谢变化, 并对其叶绿素的降解进行动力学模型拟合。结果 采后小白菜贮藏过程中总叶绿素、叶绿素a、叶绿素b、β-胡萝卜素和叶黄素均发生不同程度的降解, 低温和冰温贮藏均可减缓其降解, 其中冰温贮藏减缓效果最佳。叶绿素a含量与叶绿素b含量的比值、β-胡萝卜素含量与总叶绿素含量的比值以及室温贮藏条件下叶黄素含量与总叶绿素含量的比值均呈现不同程度的上升趋势, 而低温和冰温贮藏环境中的叶黄素含量与总叶绿素含量的比值总体则呈现下降趋势, 但贮藏6 d后下降不显著。此外, 叶绿素的降解反应符合零级动力学反应模型, 拟合调整决定系数(Adj.R2)均大于0.93, 降解活化能为95.53 kJ/mol, 降解动力学模型为k=6.51×1015?exp(9.553×104/RT)。结论 采后小白菜贮藏过程中叶绿体色素的代谢变化受贮藏温度影响较大, 其叶绿素降解反应符合零级动力学反应模型。     

基于可见光谱参数的烤烟叶片叶绿素含量估算模型

为快速、无损、准确地估计烟草叶绿素含量,通过品种和氮素水平双因素试验,获得叶片数字图像和叶片叶绿素含量数据集,分析叶片可见光谱参数与叶绿素含量参数间的关系并选择最佳参数建立估测模型。结果表明,烤烟品种和氮素水平互作增加了叶绿素与光谱参数的变异性;在3类颜色指标中,NRI、R/（G+B）、（R-B）/G、（G-R）/（R+G+B）、（R-B）/（R+G+B）、ExR与叶绿素指标达到极显著相关（p<0.01）,其中R/（G+B）与Chl.a、Chl.b、Chl.（a+b）之间的相关系数分别为-0.632、-0.636、-0.666,相关性表现最好;利用田间试验进行验证,R/（G+B）对叶绿素指标的预测精度最高,与Chl.a、Chl.b、Chl （a+b）之间的均方根误差值分别为0.6069、0.1567、0.7575;选择R/（G+B）作为叶绿素含量估测的最佳颜色指标。利用该方法可实现智能手机对烟草叶绿素含量进行快速测定,及时指导烟田施肥和采取合适的栽培管理措施,具有可期的应用潜力。     

贵州烤烟色素含量和颜色值随生育期的变化及其相关性

为了进一步探讨贵州烤烟生长特性,以K326、毕纳1号、贵烟1号、贵烟2号和K326有机烟为材料,研究了大田生育期（35、70、105 d）烟叶质体色素含量和颜色参数值的变化幵进行了相兲分析。结果表明,生育期烤烟烟叶质体色素含量和颜色参数（H＊除外）值均呈逐渐下降的趋势。毕纳1号35 d和105 d质体色素含量显著高于其他材料;K326有机烟70 d和105 d质体色素含量显著低于其他材料,但其L＊、b＊和C＊值显著高于其他材料。不同烤烟材料生育期烟叶L＊和H＊值差异均显著,且b＊和C＊值105 d显著高于35 d和75 d。不同烤烟材料烟叶质体色素含量与颜色参数值相兲均显著,其中质体色素含量与L＊、a＊值相兲系数较大,在0.805~0.866之间。线性回归分析表明,变量叶绿素b R2值（R^2=0.915）最大,变量类胡萝卜素R2值（R2=0.847）最小;自变量中线性回归系数正值Xa＊最大,其次是XH＊。相对类胡萝卜素,烤烟生育期烟叶叶绿素含量与颜色参数值的线性回归性更好。     

基于BP神经网络的烟草叶片质体色素高光谱反演

为促进高光谱遥感技术在烟叶品质监测中的应用,以云烟87为研究对象,设置不同的光质处理,测定了不同生育时期烤烟叶片的质体色素(叶绿素a、叶绿素b和类胡萝卜素)含量(质量分数)及相应的叶片光谱反射率。采用小波能量系数提取法将原始光谱数据从2 151个降维为21个,并分别建立了以质体色素实测值作为输出因子,降维后的光谱数据作为输入因子的BP神经网络预测模型,训练函数采用L-M优化算法函数trainlm,输入层和输出层传递函数分别为S型正切传递函数tansig和线性传递函数purelin,叶绿素a、叶绿素b和类胡萝卜素的神经网络的隐含层节点数分别为27、32和45。结果表明,叶绿素a、叶绿素b和类胡萝卜素各模型决定系数R2分别为0.84、0.86和0.76;均方根误差RMSE分别为0.12、0.14和0.10;相对误差绝对平均值K分别为0.23、0.21和0.15。3种质体色素模型的拟合精确度均较高,误差较小,整体效果良好。     

黄金芽茶鲜叶加工过程中色泽变化及内在原因分析

探究黄金芽茶鲜叶加工过程中的色泽变化及其内在原因,以期为黄金芽及此类白化茶树品种鲜叶的加工生产提供一定理论指导。以常规茶树品种鸠坑作为对照,分析黄金芽鲜叶在受热加工过程中外观色泽和内在呈色物质含量的变化,采用UPLC法分析叶黄素、β-胡萝卜素、叶绿素a、叶绿素b、脱镁叶绿素a及脱镁叶绿素b等6种脂溶性色素含量。研究结果表明,黄金芽鲜叶杀青后外观颜色由黄变绿,色差a*值由正值(红色)变为负值(绿色),以叶黄素为代表的黄色素含量显著降低,导致绿色素与黄色素含量比值显著上升,呈现鲜绿色;而后续的闷黄工序可使茶叶外观色泽恢复黄色,原因在于闷黄可使茶叶中的叶绿素a/b含量显著下降,绿色素与黄色素含量比值显著降低,使得闷黄后的成品茶外观色泽和色素含量均与鲜叶更为接近,黄金芽鲜叶的色泽优势由此得以凸显。     

烤烟成熟过程中鲜烟颜色值与色素含量变化及相关分析

为研究烤烟成熟过程中鲜烟叶颜色值与色素含量的变化以及相关性,测定了各部位4 个成熟度鲜烟叶的颜色值和色素含量,并进行了相关性分析.结果表明,在烟叶成熟过程中,各部位烟叶的亮度值L＊、红度值a＊、黄度值b＊均不断增大,且各部位烟叶不同成熟度间各颜色值差异显著性不同,颜色值变化趋势存在差异,其中,中、上部叶红度a＊值变化较大,增幅显著.各部位烟叶叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量均逐渐减小,类叶比值不断增大.下、上部叶类叶比值增幅基本保持不变,而中部烟叶黄绿面积在70%～80%到80%～90%时类叶比值增幅较大.各颜色值均与各色素含量、类叶比值呈显著或极显著性相关关系.表明成熟过程中烤烟叶片颜色值与色素含量关系密切,叶片颜色值变化可以指示烟叶各色素含量的变化,可以将色差计作为判断烟叶成熟度的辅助工具.     

基于图像分析检测青菜叶绿素含量

为研究利用图像分析技术快速测定青菜叶绿素含量的方法,本研究将青菜分别置于不同环境进行贮藏,采用图像分析技术和分光光度计法测定了贮藏期间青菜叶颜色参数值(L*、a*、b*、ΔL*、Δa*、Δb*、(Δa*2+Δb*2)1/2、色差ΔE)和叶绿素含量,并使用不同函数模型(y=Ax+B、y=A/x+B、y=Alnx+B和ln(lny)=Alnx+B)对颜色参数和叶绿素含量进行拟合分析。结果表明:不同贮存环境下,青菜叶颜色参数ΔE与叶绿素含量之间存在稳定的线性关系,可以用函数模型y=Ax+B进行表达。利用图像分析技术建立青菜叶颜色参数ΔE与叶绿素含量之间关系定标模型相关系数为0.990 9,其定标均方根误差为0.071 7,用未参与定标的纸盒贮藏青菜叶作为预测集,其预测相关系数为0.992 8、预测均方根误差为0.010 4。     

基于CV-ANN技术的花椒色素类成分含量快速无损检测研究

目的:通过探索花椒颜色和色素类成分含量的相关性,为花椒品质的快速评价提供参考依据。方法:采用机器视觉(CV)技术客观量化不同来源花椒的颜色;分别测定花椒样品中黄酮、多酚、花青素以及叶绿素的含量;采用SPSS 20.0软件分析花椒颜色与色素类成分之间的相关性;借助matlab工具箱采用人工神经网络(ANN)训练建模,根据花椒的颜色值预测花椒色素类成分含量。结果:花椒黄酮、多酚和花青素含量与L*值呈显著负相关,与a*值呈显著正相关;叶绿素含量与a*值呈显著负相关,与b*值呈显著正相关;花青素含量与b*值呈显著负相关。人工神经网络模型中,花椒黄酮、多酚、花青素和叶绿素的预测值与实测值相关系数分别为0.9881,0.8797,0.9842,0.9854。结论:花椒颜色与色素类成分含量密切相关,通过机器视觉-人工神经网络联用技术能够实现花椒色素类成分的快速无损检测,达到快速评价花椒品质的目的。     

粉单竹竹青色素提取工艺及其成分分析

以乙醇为提取溶剂,采用超声波提取粉单竹竹青色素,通过单因素实验,获得竹青色素最佳提取条件为:乙醇浓度90%,料液比1∶35,超声时间40 min,超声温度55℃,提取两次。实验结果表明,在最佳提取条件下粉单竹竹青叶绿素提取率为0.39%;色素纯化后通过柱层析分离得到橙黄色、蓝绿色、黄色、绿色4种色素,在紫外可见光区(400~800 nm)测4种色素紫外光谱图,发现该图形分别与叶绿素a、叶绿素b和两种类胡萝卜素的谱图相似;通过核磁共振分析,纯化后的提取物中可能含有脂肪酸,甾醇等;通过红外光谱分析可知,提取液中含有羟基、C=C双键、C=O双键、C—O键等官能团。     

Reducing tobacco addiction through tobacco product regulation

Tobacco product regulation has the potential to help reduce tobacco attributable disease by reducing the toxicity of these products and by reducing the prevalence of tobacco use and addiction.     

部分烟草种质主要病害抗性分析

通过频率分布及多样性评价,对1000多份种质的7个主要病害抗性进行了分析.结果表明,我国烟草种质资源大部分均为感病以上品种.TMV抗性资源相对较丰富,高抗或免疫种质达17%.其余病害抗病资源中,多为抗病或中抗,高抗种质很少,不到2%.我国主要病害抗性种质较为匮乏.     

Determination of perchlorate in tobacco plants and tobacco products

Previous field and laboratory studies with vascular plants have shown that perchlorate is transported from perchlorate fortified soils and is accumulated in the plant tissues and organs. This paper contains results of preliminary investigations on the occurrence of perchlorate in tobacco plants grown in soils amended with a fertilizer whose nitrogen content is derived from naturally occurring sodium nitrate (Chile saltpeter). Ion chromatography (IC) and capillary electrophoresis (CE) were used for quantitative analysis, while nuclear magnetic resonance (NMR) spectroscopy was used for qualitative analysis of perchlorate. Results show that perchlorate is accumulated by tobacco plants into the leaves from soils amended with fertilizers that contain perchlorate. Also, perchlorate can persist over an extended period of time and under a variety of industrial processes as shown by its presence in off-the-shelf tobacco products including cigarettes, cigars, and pouch and plug chewing tobaccos in concentrations ranging from nd to 60.4 +/- 0.8 mg/kg on a wet weight basis.     

Endotoxins in tobacco smoke: shifting tobacco industry positions.

In the 1980s, the tobacco industry started a campaign to divert attention away from secondhand tobacco smoke (SHS) as a major source of indoor air pollution in workplaces by highlighting the roles of other indoor air pollutants. The industry, working through "third parties," highlighted endotoxins, naturally occurring substances that cause numerous inflammatory reactions in humans, as an alternative explanation to SHS as causing indoor air problems. In 1995, Hasday and colleagues were the first to present findings that cigarette smoke contains significant quantities of endotoxins. This discovery surprised tobacco industry scientists. The 1999 publication of the full Hasday et al. findings received only limited media attention but got the full attention of Philip Morris scientists concerned about a new public health issue and a new basis for regulation of workplace smoking by the U.S. Occupational Safety and Health Administration, which already regulated workplace endotoxin exposures from other sources. Philip Morris undertook an internal endotoxin research project to test the Hasday et al. findings and to determine if endotoxin-free cigarettes were possible. Although experiments were conducted to remove endotoxin from the tobacco, there is no evidence that they were successful. Following confirmation of SHS as an important source of endotoxins, the scientist promoting endotoxins as an important indoor air pollutant for the tobacco industry softened his position on the role of endotoxins as indoor pollutants. The presence of endotoxins in SHS provides an additional mechanism for the adverse effects of SHS that should be researched further, and the risk of exposure should be assessed.     

不同烟区烤烟含钾量差异初步研究

在3个烟区（山东安丘，贵州湄潭和福建永定）采用相同品种（K326）完成的一组四处理（无肥、饼肥、烟草专用肥，饼肥加烟草专用肥）大田试验结果。结果表明，不同烟区烤烟团棵期茎叶中的含钾量相似，随烟株进入旺长期和成熟期，不同烟区的烟叶含钾量出现明显差异，石灰性土壤烟区（山东安丘）烤烟旺长期叶片和初烤叶的含钾量（K％）仅为酸性土壤烟区（福建永定）的60％－40％。作者认为，这种差异的基本原因，是不同烟区土壤溶液中阳离子含量和组成的差异，石灰性土壤溶液中活性Ca,Mg的含量高，在与阳离子K的竞争中处于优势，抑制了烟株对钾的吸收，同时还提供了若干有助于提高烤烟含钾量的措施。     

烟草种质材料TSNA含量的关联分析

摘要:利用分布于烟草24个染色体的具多态性的SSR标记和MFLP标记,分析24份烟草种质材料的遗传多样性,在此基础上对烟叶中烟草特有亚硝胺（TSNA）含量的表型变异与标记多态性进行关联分析。结果显示,33对MFLP引物和28对SSR引物在24份烟草材料中共发现188个多态位点;群体结构分析将24份烟草材料分为3个亚群,且亚群划分与烟草类型（烤烟、晾晒烟和白肋烟）基本一致;关联分析发现1个SSR位点和6个MFLP位点至少与1种TSNA含量的相关性在P<0.01水平上显著,其中标记MFLP26与烤后烟叶中NNN含量的相关性极显著（P<0.001）,表型变异解释率最高（R2=0.5831）。因此,这些显著关联的分子标记可为筛选低TSNA含量的烟草材料提供参考。      

Green tobacco sickness

OBJECTIVE—To describe the health impact of harvesting tobacco and to suggest prevention and risk reduction strategies to avoid contracting green tobacco sickness (GTS).
DATA SOURCES—A literature search of Medline, Toxline, and Toxline65 with the terms "green", "tobacco", and "sickness" covering the years 1966-1998.
STUDY SELECTION—All studies, reviews, and commentaries that provided information on the health effects of harvesting green tobacco and disease prevention strategies.
DATA SYNTHESIS—GTS occurs when tobacco workers hand-harvest, cut, or load tobacco plants, usually in the early morning or after a rainfall when tobacco plants are covered with moisture. GTS occurs through skin exposure to dissolved nicotine from tobacco leaves. Symptoms of GTS include weakness, headache, nausea, vomiting, dizziness, abdominal cramps, breathing difficulty, abnormal temperature, pallor, diarrhoea, chills, fluctuations in blood pressure or heart rate, and increased perspiration and salivation. The onset of the illness is three to 17 hours after exposure and the duration of illness is one to three days. Initial treatment includes cessation of work, change of clothing, showering, fluid intake, and rest. In more extreme cases, intravenous rehydration, anti-emetics, and dimenhydrinate are administered. Protective, water-resistant clothing; chemical-resistant gloves, boots, and socks; working in dry conditions; and dimenhydrinate can reduce the likelihood of contracting GTS.
CONCLUSIONS—It is important to provide education to tobacco workers and employers about GTS. An international public awareness campaign about GTS timed to coincide with the tobacco harvest, along with enforced worker safety regulations, should be undertaken to protect the health of individuals working in tobacco production.