烟叶腺毛研究进展

烟叶腺毛作为烟草香气物合成的主要场所,对烟叶的香气品质有重要贡献。该文综述了烟草腺毛的分泌活动、分泌物提取分析方法及组分、腺毛类型、结构和密度的研究现状,阐述了烟草腺毛与烟叶品质的关系,展望了烟叶腺毛当今的研究方向和途径,提出了烟叶腺毛及其与烟叶香气质量研究的意义和目的,以期为烟叶腺毛与烟叶品质关系的进一步研究提供参考。     

不同部位成熟烟叶腺毛密度及其分泌物的研究

针对烟叶腺毛及其分泌物含量受烟株发育阶段的影响,采用广视野显微镜和GC/MS,分析研究了烤烟K326品种不同部位成熟叶片腺毛密度及其分泌物的变化情况。结果表明：不同部位成熟烟叶腺毛密度表现为下部＜中部＜上部;中部烟叶分泌物中的α-西柏三烯-4-醇、β-西柏三烯-4-醇、α-西柏三烯-4,6-二醇、β-西柏三烯-4,6-二醇的含量分别比下部烟叶增加了282%、240%、48%、80%,上部烟叶的上述四种分泌物的含量分别比下部烟叶增加了991%、687%、74%和129%。这说明对于同一烤烟品种,随部位的升高,烟叶腺毛密度增大,腺毛分泌物主要成分的含量也在增加。     

不同生态条件下烟草品种烟叶腺毛密度的变化

对7个烤烟品种在4个生态区烟叶腺毛密度的电镜扫描测定,结果表明：品种间、生态间烟叶的腺毛密度差异较大,且有一定的变化规律;生态因素和品种因素对烟叶腺毛密度均有较大的影响,但生态因素是影响烟叶腺毛密度的主要因素。烟叶腺毛密度与烟叶的品质有关,为此,根据品种间、生态间烟叶特有的腺毛密度特性,可以估测烟叶品质和烟草品种在不同生态区的适宜种植程度,为烟草品种的合理布局和区域化种植提供科学依据     

超量表达AtBAS1基因影响烟草叶片腺毛发育

烟叶腺毛是烟草(Nicotiana tabacum)香气物质合成的主要场所,对烟叶的香气品质有重要影响。为探索拟南芥(Arabidopsis thaliana)光敏色素B激活标签的抑制蛋白1(phyB activation-tagged suppressor1,BAS1)基因对烟草叶片腺毛发育的影响,构建pSH-35S-BAS1超量表达载体遗传转化烟草,对烟草叶片腺毛发育进行研究。结果表明转基因烟草腺毛数量比野生型烟草腺毛提高了32.5%,推测BAS1基因的表达可能引起了腺毛发育相关基因表达的改变。根据研究报道烟草萜类化合物环化酶基因(nicotiana tabacum cultivar T.I.1068 cyclase gene,NtCTTC)、细胞色素P450加氧酶基因(nicotiana tabacum cytochrome P450 gene,CYP71D16)和烟草表面抗性蛋白基因(nicotiana tabacum phylloplanin,NtPhP)均在腺毛上特异性表达。通过q-PCR分析烟草腺毛发育的相关基因在转基因烟草和野生型烟草中的表达情况,得到结果,NtCTTC、CYP71D16和NtPhP基因在转基因植株中的相对表达量分别是野生型植株中的34.16、1.26和8.95倍。综上可知,BAS1基因在烟草中超量表达引起了腺毛发育相关基因表达的上调,从而增加了烟草腺毛的数量。本研究为外源基因对烟草腺毛密度以及调控烟草腺毛发育研究提供了借鉴。     

烤烟EMS诱变后代高香气突变体筛选

为筛选高香气且品质较优的烤烟后代,以中烟100为材料,采用EMS诱变技术对中烟100种子进行处理,筛选出2个叶面腺毛密度大的突变体材料,通过田间试验,对其叶面腺毛密度、叶面化学成分、烤后化学成分、香气物质含量和感官质量评吸等指标进行评估,并与正常中烟100后代和NC89进行对照。研究结果表明,EMS-2诱变株系腺毛密度最大,为65.55个/mm ²,分别是中烟100（37.19个/mm ²）和NC89（56.06个/mm ²）的1.8和1.2倍;叶面化学成分分析结果表明,EMS-1诱变株系西柏烷类和烷烃类含量最多,分别为57.18、5.16mg/m ²,EMS-2突变株系蔗糖酯类物质分泌较旺盛,含量最多,为0.33mg/m ²;烤后样化学成分分析结果表明,EMS-2突变株系化学成分含量较协调,且香气成分含量最多,达到890.32μg/g,分别比中烟100和NC89增加34.5%和29.0%;结合对诱变后代的感官评价,得出结论：诱变株系综合品质较好,可提高烟叶质量,EMS-2综合品质最好,可以作为待选株系进行下一步品种选育。     

不同营养配比对烤烟腺毛密度和石油醚提物含量的影响

通过烟株根部营养和叶面营养试验,研究了不同营养配比对烤烟腺毛密度和石油醚提物含量的影响。结果表明:不同营养配比对腺毛密度和石油醚提物含量均有一定的影响。在根部营养试验中,中、上部烟叶腺毛密度的差异均达到0.05显著水平,通过根部营养可以提高烟叶的腺毛密度,其中以配施饼肥处理的效果最好。中部叶石油醚提物含量的差异未达到0.05显著水平,说明烟叶腺毛密度与石油醚提物含量并不存在必然的联系,石油醚提物含量的高低可能还与烟株腺毛的分泌能力和生长环境有关。叶面营养的喷施同样可以提高烟株石油醚提物含量,其中以喷施醋酸 饼肥水 ZnSO4的效果最好。K326中下二棚烟叶腺毛密度变化幅度较大,其它叶位变化幅度较小。     

烤烟腺毛的形态学观察和密度研究

为了开展烤烟品种间的腺毛形态和腺毛密度的规律性研究,以7个烤烟品种为试验材料,在扫描电子显微镜和光学显微镜下对烤烟腺毛的形态进行了观察,并对腺毛的数量和分布进行了统计、分析和研究。结果表明,烤烟腺毛根据柄细胞的数量分为长柄腺毛和短柄腺毛,长柄腺毛是烤烟叶片表面的优势腺毛,短柄腺毛的发生较晚、数量稳定,其头部分泌细胞体积小、数量较多。7个烤烟品种中除‘龙江911’以外均表现为下表面的腺毛密度大于上表面的腺毛密度,烤烟叶片下表面的腺毛密度更能反映出品种的腺毛密度特征。长柄腺毛在烤烟叶片腺毛总体中所占的比例远大于短柄腺毛,对叶片腺毛总体密度的影响最大;短柄腺毛虽然所占的比例相对较小,但是其对烟叶香气的贡献是不可忽视的。腺毛密度在不同的烤烟品种间具有一定的特征性,按照叶片上、下表面的腺毛密度平均值排列顺序是：‘吉烟7号’>‘龙江915’>‘龙江851’>‘K346’ >‘NC89 ’>‘龙江911’>‘CF978’。     

基因型和生态因素对烟草香气物质含量的影响

香气物质是反映烟叶质量的重要品质因素。烟叶的香气质、香气量和香型风格是由多种香气成分的组成、含量、比例及其相互作用所决定的。烟叶香气表现型受遗传因素和环境因素共同作用,遗传因素影响香气物质的性质和种类,环境因素则主要影响香气物质的含量和组成比例。当前,烟叶香气不足是影响中国烟叶质量提高的制约性因素。在此,综述了基因型和生态环境因素对烟草香味成分影响的研究概况。     

烤烟烟叶腺毛分泌物提取方法初探

为探索烤烟烟叶腺毛分泌物提取效果最佳的方法,以烤烟品种K326、云烟85和红花大金元为材料,采用二氯甲烷作为溶剂,比较不同提取级数和不同提取时间前后叶片重量的变化。结果表明,在烟叶腺毛分泌物提取方法的不同提取级数的效果比较中,3个烤烟品种均以前3级提取的变化最明显,而之后增加提取级数,叶片重量变化不明显;不同提取时间对叶片的重量变化影响不大。这说明采用3级提取作为烤烟叶片腺毛分泌物的提取方法比较适宜     

糖酯在烟草中的应用研究进展

糖酯是烟叶表面分泌物中的主要成分之一,也是在卷烟中广泛应用的一种重要香味前体物质,糖酯在烟草中的应用与研究日益得到关注。综述了糖酯作为香味前体物对卷烟香气的影响,作为保润剂对卷烟保润性能的影响、作为烟叶表面分泌物对烟叶外观质量等方面的应用研究进展,旨在为糖酯在烟草中进一步的应用研究提供参考。     

Effects of glandular trichomes on the development of Phytophthora infestans infection in potato (S. tuberosum)

S. berthaulltii Hawkes, a wild potato species, possesses two types of glandular trichomes on its leaf surface: types A and B wich confer resistance to insects. Preliminary results indicated that the presence of glandular trichomes also confers resistance to Phytophthora infestans, the causal agent of late blight. In this paper we report the evaluation of trichome characteristics (density and exudate activities) performed on 8 lines of potato, including the control varieties Desirée and Tropicana, 5 hybrid lines derived from intercrosses and backcrosses between S. tuberosum and S. berthaultii and one accession of S. berthaultii. Whole plants of the 8 genotypes were inoculated with a spore suspension of Phytophthora infestans in order to evaluate their resistance to late blight. The resultant disease incidence correlated negatively with type A trichome density and with polyphenol-oxidase (PPO) activity of type A trichome glands. The removal of type B trichomes exudate by leaf dipping in ethanol did not influence the disease development after artificial inoculation of detached leaves. Type B trichome exudate was extracted and the fraction corresponding to Fatty Acids Sucrose Esters (FASE) was recovered after Thin Layer Chromatography and tested on the fungal mycelium in vitro. The FASE exhibited a slight inhibitory effect on mycelium growth. The results of the experiments are discussed, and several hypotheses regarding the possible role of types A and B trichomes are formulated. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of type IV glandular trichome density and its association with whitefly resistance from <Emphasis Type="Italic">Solanum galapagense</Emphasis> accession LA1401

Tomato is affected by a large number of arthropod pests, among which the whitefly (Bemisia tabaci) is considered to be one of the most destructive. Several accessions of the wild species of Solanum galapagense, including accession LA1401, are considered resistant to whitefly (B. tabaci). This resistance has been associated with the presence of type IV glandular trichomes on the leaf surface. Our research aimed to study the inheritance of type IV glandular trichome density and its association with resistance to whitefly (B. tabaci biotype B) in populations derived from the interspecific cross Solanum lycopersicum × S. galapagense ‘LA1401.’ High estimates for both broad-sense and narrow-sense heritabilities of type IV glandular trichome densities suggest that inheritance of this trait is not complex. Whitefly resistance was associated with high density of type IV glandular trichomes. F₂ (S. galapagense × S. lycopersicum) population plants selected for the highest densities of type IV glandular trichomes showed similar levels of resistance to those found in the donor of resistance LA1401.     

Inheritance of trichomes and resistance to pod borer (Helicoverpa armigera) and their association in interspecific crosses between cultivated pigeonpea (Cajanus cajan) and its wild relative C. scarabaeoides

The legume pod borer, Helicoverpa armigera, is one of the most devastating pests of pigeonpea. High levels of resistance to pod borer have been reported in the wild relative of pigeonpea, Cajanus scarabaeoides. Trichomes (their type, orientation, density and length) and their exudates on pod wall surface play an important role in the ovipositional behavior and host selection process of insect herbivores. They have been widely exploited as an insect defense mechanism in number of crops. In the present investigation, inheritance of resistance to pod borer and different types of trichomes (A, B, C and D) on the pod wall surface in the parents (C. cajan and C. scarabaeoides) and their F₁, F₂, BC₁ (C. cajan × F₁), and F₃ generations has been studied. Trichomes of the wild parents (high density of the non-glandular trichomes C and D, and glandular trichome B and low density of glandular trichome A) were dominant over the trichome features of C. cajan. A single dominant gene as indicated by the segregation patterns individually will govern each trait in the F₂ and backcross generation. Segregation ratio of 3 (resistant): 1 (susceptible) for resistance to pod borer in the F₂ generation under field conditions was corroborated with a ratio of 1:1 in the backcross generation, and the ratio of 1 non-segregating (resistant): 2 segregating (3 resistant: 1 susceptible): 1 non-segregating (susceptible) in F₃ generation. Similar results were obtained for pod borer resistance under no-choice conditions. Resistance to pod borer and trichomes associated with it (low density of type A trichome and high density of type C) are governed individually by a dominant allele of a single gene in C. scarabaeoides. Following backcrossing, these traits can be transferred from C. scarabaeoides into the cultivated background.     

芝麻叶腺毛显微结构及干旱条件下腺毛分泌物的变化

通过扫描电镜观察芝麻苗期叶片表面腺毛的显微结构,以二氯甲烷作为溶剂提取腺毛分泌物,并用GC/MS鉴定正常和干旱条件下不同芝麻品种叶片腺毛次生代谢物的差异。结果显示,苗期芝麻叶片表面存在非腺体腺毛、长柄腺毛、短柄腺毛及无柄黏液毛等多种腺毛类型,叶表面气孔属于毛茛型;芝麻叶腺毛分泌物包含多种组分,其中峰面积>2%的组分是主要代谢物,主要由酯类及直链饱和烷烃物质组成,品种间具有显著差异;干旱条件下,分泌物的组分显著改变,抗旱性较强的冀9014有10个组分的相对含量高于其他品种,这些组分包含三十六烷与三十四烷类物质。上述结果表明,用GC/MS鉴定芝麻叶表面腺毛分泌物是可行的,分泌物组分可以反映品种间的差异,并能揭示干旱条件对芝麻代谢的影响。可以认为,芝麻腺毛与腺毛分泌物组分在芝麻种质资源鉴定及抗旱种质选育中具有重要的应用价值。     

菜籽饼肥对邵阳烟叶品质及经济效益分析

为解决邵阳烟叶香气量不足、香气质差的问题,提高邵阳烟叶质量,以烤烟品种‘K326’为试验材料,研究在大田条件下不同菜籽饼肥用量对烟叶品质和效益的影响。结果表明：在目前邵阳推行的施肥方式下,施用饼肥375 kg/hm2饼肥,可以有效促进烟叶开片,改善烟叶内部化学成分的协调性,降低烟碱含量,提高烟叶的油份、色度,改善烟叶组织结构,提高烟叶感官评吸的质量档次,并提高产量约30~150 kg/hm2,提高产值2250~3000元//hm2。     

DNA直接导入法获得烟草新品系

为解决烟草栽培品种香气品质低下的问题,选用香料烟品种Ti245、高密度腺毛品种Ti1068、浓香型品系6251为供体,将三者总DNA混合后经花粉管通道导入烟草栽培品种K326;后代产生了广泛变异,经过连续3年的选育,获得了优良品系K809。与受体K326相比,K809田间农艺性状优良、叶片腺毛密度增加、香气物质含量大幅度提高,评吸结果表明香气品质得以改善;RAPD分子检测发现,K809含有来源于受体和供体的所有片段,一些片段仅与某供体特异同源,表明供体Ti245、Ti1068、6251的某些DNA片段在K809基因组中进行有效了整合,并且对烟叶的香气品质具有积极作用。