不同耐肥性烤烟品种成熟期叶片质外体生理特性研究

采用盆栽试验,以对氮肥敏感烤烟品种NC89和耐氮肥烤烟品种中烟100(ZY100)为材料,研究了不同耐肥性烤烟品种成熟期叶片质外体生理特性差异。结果表明,成熟期2个烤烟品种叶片总氮含量呈逐步下降趋势,NC89总氮含量下降幅度较小,且总氮含量极显著高于中烟100。不同耐肥性烤烟品种成熟期叶片质外体NH4+浓度呈上升趋势,而质外体pH值、氨气补偿点呈下降趋势,中烟100变化幅度较大,NC89变化幅度较小。中烟100成熟期叶片质外体NH4+浓度、pH值和氨气补偿点均极显著高于NC89。研究表明,不同耐肥性烤烟品种成熟期叶片质外体生理特性具有明显差异,导致不同烤烟品种间叶片总氮含量具有显著差异,耐氮肥烤烟品种通过叶片质外体以氨挥发形式损失氮素的能力较强。     

不同氮素利用效率基因型烤烟叶片衰老期间氮素代谢差异研究

选用氮素利用效率差异较大的两个烤烟基因型中烟100和K326,采用喷施谷氨酰胺合成酶(GS)抑制剂(Glufosinate)和质外体提取等方法分别测定叶片衰老过程中叶片的氮素代谢产物和相关酶活性的变化,并计算气孔氨气补偿点,研究了烤烟叶片衰老期间氮素的转移和再利用特性与氮素利用效率的关系。结果表明,氮低效基因型烤烟中烟100衰老时间早、速度快,GS和NR活性低,GDH活性高,氨气挥发量大,对叶片NH4+的积累反应速度快,再转移量大,与氮高效基因型烤烟K326相比差异显著。说明烤烟叶片衰老期氮素的再转移和再利用,与叶片衰老程度和速度密切相关。     

浓香型烟叶特色品种衰老期的氮素代谢特性

为揭示浓香型特色烟叶形成的生理生化基础,采用质外体提取等方法分别测定了具有浓香型特色的烤烟品种NC89和对照品种89112烟叶衰老过程中的氮素代谢产物和相关酶活性的变化,并计算了氨气补偿点。结果表明,与89112相比,NC89品种叶片总氮和可溶性蛋白含量较高,在衰老过程中谷氨酰胺合成酶(GS)活性下降幅度小,谷氨酸脱氢酶(GDH)活性低;质外体铵离子浓度和质外体pH变化相对平缓,氨气挥发高峰期氨气补偿点偏低,氨气挥发潜力较小,最终总氮减少量较小。     

谷氨酰胺合成酶抑制剂对衰老期烟叶氮代谢的影响

通过质外体提取和测定氮素代谢相关酶等方法,调查了不同浓度谷氨酰胺合成酶（GS）抑制剂（Glufosinate）对2个氮效率烤烟品种氮代谢相关生理指标的影响。结果表明,GS抑制剂可以有效抑制衰老期间烟叶GS活性,使氮素再同化能力下降,促进氮素营养物质的降解,并诱导谷氨酸脱氢酶（GDH）活性升高和硝酸还原酶（NR）活性下降,使叶片NH₄⁺积累,增大了氨气挥发潜力,且随着GS抑制剂浓度的升高,抑制效果更加明显。氮低效品种与氮高效品种相比,衰老速度快,叶片NH₄⁺的积累量小,氨气挥发潜力大,品种间差异显著。GS抑制剂可以加速叶片衰老,促进氮素降解和再转移。     

氮素营养水平对衰老期烟叶氮代谢的影响及品种间差异

为揭示品种间烟叶品质的差异和筛选耐氮肥品种,研究了烤烟品种在不同氮素营养条件下氮代谢的差异。结果表明:氮低效与氮高效品种相比,可溶性蛋白和总氮降解量大,谷氨酰胺合成酶（GS）活性低,降幅大,谷氨酸脱氢酶（GDH）活性高,硝酸还原酶（NR）活性低,氨气补偿点高,品种间差异显著。随着施氮量的增加,氮低效品种氮素营养物质降解量百分数高,GS活性降幅大且受施氮量影响较小,GDH活性和氨气挥发潜力增大,与氮高效品种相比差异显著。NC89和豫烟10号分别在施氮量在45.00和60.00 kg?hm-2时氮代谢生理强度最大,而且豫烟10号各处理间差异小于NC89。说明不同氮效率品种烟叶的氮素再同化和转移能力存在差异,氮低效品种对氮素再同化量小,再转移量大,对氮素的应用范围广,调节能力强,而氮高效品种再同化量大,转移量小,对氮素的应用范围小,调节能力弱。烟叶衰老期氮代谢与烟叶衰老速度有关,其中GS对NH4+的再同化能力和质外体对NH4+的转移能力起主导作用。      

Mo肥对烟叶产量品质的影响

通过不同浓度、不同时期和不同方法对烤烟施用Mo6+的试验表明烤烟施Mo6+的协调,烟株生理代谢,改善烟株植物学性状,使烟叶增产、增质.试验各处理以浓度0.5g/kg(NH4)6Mo7O24·4H2O在还苗期叶面喷施1次效果最佳,浓度1.5g/kg(NH4)6Mo4O24·4H2O在团棵期叶面喷施2次及浓度2.5g/kg(NH4)6Mo7O24·4H2O在旺长期根部浇施1次的效果居第2位,施Mo6+处理均优于对照.     

津巴布韦引进与云南主栽烤烟品种腺毛密度及分泌物的差异

为了解津巴布韦引进品种(津引品种)特性,筛选出适宜云南玉溪烟区种植的品种,采用显微观察活体叶片、GC/MS法分析了津引烤烟品种KRK22,KRK23,KRK26,T29和云南主栽品种K326,红花大金元(红大)上、中、下3个部位成熟期叶片腺毛密度及叶片腺毛分泌物.结果表明:①不同烤烟品种间烟叶腺毛密度差异显著,红大、K326腺毛密度最大,显著高于津引品种KRK23和KRK22;②不同烤烟品种间烟叶腺毛分泌物含量差异显著,K326、红大的腺毛分泌物总量最多,显著高于津引品种KRK23.腺毛密度和分泌物量间呈显著正相关,但不是线性关系.从腺毛密度和腺毛分泌物等与烟叶品质较密切的性状来看,表现较好的为云南主栽品种K326和红大,优于津引品种,综合表现较差的为KRK23.     

不同烤烟品种烟叶衰老特性与内源激素的关系

为明确不同烤烟品种烟叶衰老特性与内源激素变化的关系,以田间成熟落黄表现不同的4个烤烟品种(豫烟10号、云烟87、K326和NC89)中部叶为材料,分析了不同品种叶片发育成熟过程中叶绿素含量(质量分数)、衰老标志基因、内源激素含量及相关基因表达量的变化。结果表明:在豫中烟区常规大田栽培条件下,随着烟株叶龄的增加叶绿素含量逐渐降低,烟叶衰老程度加剧,脱落酸(ABA)含量升高,赤霉素(GA3)、生长素(IAA)和细胞分裂素(CTK)含量降低。豫烟10号品种中部叶衰老速度较快,云烟87和K326居中,NC89衰老速度较慢。与NC89品种相比,豫烟10号品种中部叶随着叶龄的增加,ABA含量保持在较高水平,而延缓衰老的GA3、CTK和IAA含量指标均较低,衰老上调标志基因CP1和CP23的表达量较高,衰老下调表达基因PSA1和MC的表达量较低,分别调控乙烯、ABA和茉莉酸的相关基因NtEFE26、NtNCED1和NtPR1b表达量均较高,水杨酸应答基因NtCHN50的表达量较低。烤烟品种烟叶衰老特性差异与自身的激素代谢密切相关,成熟落黄快的品种表现出ABA、乙烯和茉莉酸代谢旺盛的特点。     

不同烤烟品种(系、组合)叶面分泌物和石油醚提取物变化动态

研究了高香气烤烟新品系8306和其他8个烤烟品种(系、组合)叶面分泌物和石油醚提取物的变化动态,结果表明:(1)在旺长期、成熟期和调制后,不同烤烟品种(系、组合)叶面分泌物和石油醚提取物均存在显著或极显著差异;与其他烤烟品种(系、组合)相比,8306具有较高的叶面分泌物和石油醚提取物含量;(2)烟草从旺长到成熟期,叶面分泌物含量持续增加,但调制后,极显著降低。石油醚提取物含量在上述3个时期内表现出逐步增加的趋势;(3)调制后烟叶石油醚提取物含量与旺长期和成熟期的石油醚提取物含量呈显著正相关关系,而叶面分泌物却无此规律;(4)调制后烟叶叶面分泌物和石油醚提取物含量达到极显著正相关关系,相关系数为0.82。     

成熟期大田渍水胁迫对烤烟叶片生理特性的影响

以烤烟(Nicotiana tabacum L.)品种K326为材料,在大田条件下研究了成熟期渍水胁迫对烤烟叶片生理特性的影响.结果表明:在渍水胁迫下烤烟叶片叶绿素和可溶性蛋白质含量前期下降缓慢,后期下降速度加快;丙二醛(MDA)含量随溃水时同延长而急剧升高;叶片超氧化物岐化酶(SOD),过氧化物酶(POD),过氧化氢酶(CAT)活性变化规律一致,表现为先升后降,但POD上升较缓慢.渍水超过3 d,烤烟叶片生理代谢活动受到严重伤害,很难得到恢复.     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press