外源水杨酸对低温胁迫下低温敏感性不同的烤烟品种烟叶生理特性的影响

  目的  探究低温胁迫下外源水杨酸对低温敏感型不同烤烟品种叶片生理特性的影响,并筛选最佳外源水杨酸的缓解浓度。  方法  以低温不敏感型品种红花大金元及低温敏感型品种K326为材料,通过盆栽试验研究不同浓度外源水杨酸对4℃低温胁迫下红花大金元和K326叶片相对电导率（REC）、丙二醛（MDA）含量、抗氧化酶活性、渗透调节物质含量及多酚代谢的影响。  结果  低温胁迫下,2个低温敏感性不同的烤烟品种的相对电导率、丙二醛含量、多酚氧化酶活性及苯丙氨酸解氨酶活性均显著上升,其中,K326的丙二醛含量上升幅度远大于红花大金元,达94.07%;而3个抗氧化酶活性均被显著降低,K326的可溶性糖含量及总酚含量、红花大金元的可溶性蛋白含量均显著上升。施加外源水杨酸后,K326及红花大金元的叶片相对电导率及丙二醛含量均显著降低,而3个抗氧化酶活性及苯丙氨酸解氨酶活性均显著上升,红花大金元的可溶性糖含量及可溶性蛋白含量、K326的总酚含量均显著上升;当外源水杨酸浓度为50~100 mg/L时对各个指标的缓解效果较好。  结论  外源水杨酸浓度50 mg/L处理对红花大金元及K326的缓解效果均达到最佳。      

有机和常规种植对不同烤烟品种生长发育和产值量的影响

通过对NC102、NC297、K326和红花大金元4个烤烟品种进行有机和常规种植,研究了不同种植模式对不同品种生长发育和产质量的影响。结果表明:烤烟NC297、NC102、K326和红花大金元采用有机种植后土壤中的速效氮、磷、钾、有机质含量显著升高,土壤养分由高到低为:NC102>红花大金元>NC297>K326,pH值降低;有机种植NC297、NC102、红花大金元前期生长发育较常规种植慢,进入旺长期后生长发育快于常规种植,K326生长迟缓;有机种植的处理白粉病、炭疽病和野火病发病率显著高于常规种植;有机种植第一年对NC102、NC297、红花大金元的产量、产值影响不大,而K326的产量、产值显著降低。     

低钾胁迫下不同烤烟品种根系生长和根毛形态的差异

通过琼脂平板培养技术,研究了K326、NC82、云烟85、RG11、红花大金元等5个烤烟品种低钾胁迫下根系生长和根毛形态的差异.结果表明:低钾胁迫对烟苗地上、地下部生长发育影响显著.不同烤烟品种根系对低钾胁迫的响应能力具有显著性差异,其中苗期的地上部分和根系生物呈表现为RG11受抑制程度最强,其次是红大和云85,NC82和K326最弱;根冠比下降幅度为RG11和云烟85>NC82和K326>红花大金元,以NC82根冠比最为协调;烤烟根系形态受抑制程度大致表现为:云烟85和RG11>K326和红花大金元>NC82;不同烤烟品种根系分布不同,RG11和红花大金元根系集中分布在2 cm以下,K326分布在3 cm以下,云烟85和NC82分布在3～5 cm;根毛密度增加幅度大小依次为NC82>K326>云烟85>红花大金元>RG11.综合分析得出,NC82比其它4个烤烟品种耐低钾胁迫能力高,单株根系总长度和根毛长度可作为烤烟品种的耐低钾胁迫、养分利用效率及抗逆性等的重要指标,采用平板培养技术可较准确、快捷地研究烤烟种质资源的钾营养特性.     

烤烟新品种中烟103的选育及其特征特性

中烟103是从红花大金元中获得变异株,经系统选育而成的。该品种植株结构合理,遗传性状稳定,田间长势强,易烘烤;耐TMV、CMV、PVY,中抗黑胫病,气候斑点病轻,中感根结线虫病,感青枯病和赤星病;其主要经济性状比对照品种NC89、K326或红花大金元有不同程度的提高;烤后原烟橘黄色烟比例高,结构疏松,身份中等,油分有-多,色度强-浓,外观品质总体性状优于对照品种K326;化学成分含量适宜,比例协调,与对照品种K326相比,糖、钾含量略高,烟碱、总氮含量略低。感官评吸与K326质量档次相当。中烟103是一个质量、产量、抗病较能兼顾的具有红花大金元香气特征的烤烟新品种,2007年通过全国烟草品种审定委员会审定。     

不同烤烟品种主要挥发性香气物质含量的比较与分析

采用同时蒸馏萃取-气相色谱/质谱法对云南主要烟区4个主栽品种红花大金元、K326、云烟87和云烟85共计390个样品的主要挥发性香气物质进行了分析。结果表明,红花大金元和K326品种上部和中部烟叶中主要挥发性香气物质总量、新植二烯和呋喃类化合物含量均显著高于云烟87和云烟85;红花大金元上部和中部烟叶的醇类和酚类化合物含量均显著高于K326、云烟87和云烟85,氮杂环类化合物含量则显著低于后3个品种。     

复合盐碱处理下烤烟品种发芽特性及耐盐性评价

为探讨不同烤烟种子萌发期耐盐特性,以5个烟草品种为供试材料,在发芽期采用不同质量浓度的复合盐碱处理,研究其对烟草品种主要发芽特性的影响。结果表明,低浓度盐碱(0.2%、0.4%)不同程度提高了K326、红花大金元和云烟97的发芽率和发芽势,红花大金元和K326的发芽指数也较对照有所增高;中高浓度盐碱(≥0.6%)降低了各品种种子的发芽率、发芽势及发芽指数,而干重始终随盐碱浓度增大而减小,盐害率则随浓度增大而增大。低浓度的复合盐碱促进部分烤烟品种(K326、红花大金元、云烟97)萌发,而高浓度盐碱对供试品种的萌发有强烈的抑制作用。不同品种对盐碱的耐受力不同,低盐碱下红花大金元、云烟87和K326表现相似且良好,云烟97次之,中烟100较弱;中高盐碱处理下,K326和云烟87、云烟97表现较好,红花大金元次之,中烟100较弱。     

烤烟新品种南江3号的选育及其特征特性

南江3号是从红花大金元品种中获得的自然变异株,经系统选择培育而成.该品种适应性强,易烘烤,中抗赤星病、黑胫病和青枯病,气候斑点病轻.烟叶外观品质好,烟碱含量适中,化学成分协调,烟叶吸食品质与贵州省主栽品种K326相当,符合中式卷烟发展对原料的需求.主要经济性状与K326比较,产量提高15.71%,产值增加33.93%,具有生产应用价值.     

温度和品种抗性对烟草青枯病潜育期的影响

为揭示烟草青枯病的发生流行规律,采用稀释涂布平板法确定菌悬液浓度,以K326、红花大金元、云烟85和云烟87为试验材料,利用盆栽试验筛选最佳接种方法,进而确定影响烟草青枯病侵染阈值和潜育期的关键因子。结果表明,采用菌悬液蘸根是烟草青枯病菌的最佳接种方法,与灌根法比较,蘸根法的发病时间可提早8 d;通过系列浓度梯度的菌悬液接种试验,明确了烟草青枯病的侵染阈值为3×102cfu/mL;人工气候箱盆栽试验结果显示,4个烟草品种表现出相似的发病规律,即烟草青枯病潜育期受温度影响较大,表现出潜育期随温度的升高而缩短。在最适发病期内,因品种抗性的差异,烟草青枯病潜育期为20~28 d,平均24 d,抗病性越高,潜育期越长;反之则越短。     

纳米碳溶胶对烤烟生长发育及养分吸收积累的影响

为明确纳米碳溶胶对烤烟养分吸收利用的作用效果,采用水培试验研究了不同浓度纳米碳溶胶对两个烤烟品种红花大金元(红大)和K326生长发育及养分吸收积累的影响.结果表明,适宜浓度的纳米碳溶胶能够促进烤烟植株的生长发育,当溶胶浓度为10 mg/L时,烟株地上部生物量显著提高.纳米碳溶胶还能促进烤烟对氮、钾、钙、镁的吸收,增加其在地上部的含量.两个烤烟品种养分积累量均随纳米碳溶胶浓度的升高呈先增加后降低的趋势,当溶胶浓度分别为5～10 mg/L和10～20 mg/L时,红大和K326的养分积累量达到最大.可见,水培条件下,烟株生长状况达到最佳的最适纳米碳溶胶浓度红大品种为5 ～ 10 mg/L,K326品种为10～20 mg/L.     

南方根结线虫侵染不同抗性烟草品种的组织病理学观察

分别利用烟草抗病品种K326和感病品种红花大金元研究了南方根结线虫侵染过程中的组织病理学变化。结果显示,接种后3d,2品种都能形成巨型细胞,且巨型细胞的数量和形态没有显著差异。接种后15d,感病品种中巨型细胞正常发育,而抗病品种中巨型细胞出现空泡。接种25d,抗病品种巨型细胞发生崩解。表明不同抗性品种巨型细胞的形态变化与品种的抗性有关。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the