基于相对迁移率的节节麦醇溶蛋白组成分析

为准确揭示节节麦醇溶蛋白的组成情况,对不同地理分布的212份节节麦的种子蛋白进行酸性聚丙烯酰胺凝胶电泳(A-PAGE)分析。由于麦醇溶蛋白现有的"数字字母命名"系统并不具备广泛的普适性,将普通小麦——‘中国春’(对照)第1条谱带的迁移率作为标准,其他供试材料的谱带与它的比值作为相对迁移率来确定每条醇溶蛋白条带的位置。结果显示,212份节节麦材料中共存在422种不同迁移率的谱带。所有条带可分为ω、γ、β和α4个区,α区的多态性条带最多,达34.70%。多态性条带品种间遗传相似系数(GS)的变幅为0～0.58,遗传变异较大。聚类分析结果表明,节节麦可能是以伊朗为中心向四周各地扩散传播。中国境内的节节麦至少存在3种类型。基于相对迁移率的表示方法,无需除‘中国春’以外的其他对照材料,即可有效区分A-PAGE胶上距离较近的蛋白条带,为不同麦类作物醇溶蛋白的研究提供统一标准。     

黄河中游地区粗山羊草高分子量谷蛋白亚基组成分析

为了解黄河中游地区粗山羊草的高分子量谷蛋白亚基(HMW-GS)遗传多样性,应用SDS-PAGE技术分析了56份粗山羊草Glu-Dt1位点的HMW-GS组成,检测到3种x-型亚基(5t,6.2t,null)和3种y-型亚基(10.5t,10.4t,10.3t)。其中6.2t类型是新的x-型亚基。供试粗山羊草共发现3种HMW-GS组合类型5t 10.5t,6.2t 10.4t,null 10.3t,它们的比例分别是91.07%,7.14%,1.79%。表明该地区粗山羊草的高分子量谷蛋白亚基有一定变异。     

Genetic diversity of Central Asian and north Caucasian Aegilops species as revealed by RAPD markers

RAPD analysis of 112 accessions of Aegilops tauschii Coss. (genome DD), Ae. cylindrica Host (CCDD), Ae. crassa Boiss. (DDMM), Ae. biuncialis Vis. (UUMM) and Ae. triuncialis L. (UUCC) collected in the Central Asia and north Caucasia was conducted. Aegilops accessions were divided into two major groups, corresponding to the D genome species and the U genome species. These groups were also separated into sub-groups according to species, except for the Ae. tauschii-cylindrica complex of accessions from Central Asia. Aegilops tauschii from north Caucasia was divided into two varietal groups, tauschii and meyeri. The Central Asian accessions of Aegilops species were more diverse than the accessions from north Caucasia. Aegilops tauschii and Ae. cylindrica accessions from north Caucasia were genetically uniform. Associations between altitudal variation of Aegilops species and variability of RAPD markers were not found.     

Identification in Aegilops species of resistant sources to Hessian fly (Diptera: Cecidomyiidae) in Morocco

Hessian fly, Mayetiola destructor (Say), is the major insect pest of wheat in Morocco. Host plant resistance has been the most effective and practical method of controlling this pest. When 347 accessions of Aegilops species were screened in the greenhouse for resistance to Hessian fly, several accessions of Ae. geniculata Roth, Ae. triuncialis L., Ae. neglecta Req.ex Bertol., Ae. ventricosa Tausch, Ae. cylindrica Host and Ae. markgrafii (Greuter) Hammer showed resistance reaction. All expressed antibiosis as the mechanism of resistance against first instar Hessian fly larvae. These Aegilops sources of resistance could be exploited for transferring Hessian fly resistance to wheat.     

Au Elements and Their Evolution in Some Allopolyploid Genomes of Aegilops

To study the sequences of short interspersed nuclear elements (SINEs) evolution in some allopolyploid genomes of Aegilops, 108 Au element fragments (a novel kind of plant SINE) were amplified and sequenced in 10 species of Aegilops,which were clustered into three different groups (A, B and C) based on their related genome types. The sequences of these Au element fragments were heterogonous in di-, tetra-, and hexa-ploids, and the dendrograms of Au element obtained from phylogenetic analysis were very complex in each group and could be clustered into 15, 15 and 22 families,respectively. In this study, three rules about Au elements evolution have been drawn from the results: i. Most families were composed of Au element members with different host species in three groups; ii. Family 1-6 in Group A, Family 1-6 in Group B, Family 1-4 and Family 6-13 in Group C contained only one, apparently highly degenerate Au element member (a single representative element); iii. Elements generally fell into clades that were species-specific with respect to their host species. The potential mechanisms of Au element evolution in Aegilops were discussed.     

牡山羊草细胞质雄性不育小麦败育的生物学特性和细胞学研究

为明确牡山羊草细胞质雄性不育小麦的染色体组成及雄性败育特点,采用分子标记技术和酸性聚丙烯酰胺凝胶电泳技术对牡山羊草细胞质雄性不育小麦是否含有1BL/1RS易位染色体进行了鉴定。另外,为揭示牡山羊草细胞质雄性不育小麦败育发生的时期和败育的细胞学机理,以牡山羊草细胞质雄性不育小麦(Ju87B1-706A)和其同型保持系(706B)为供试材料,采用I2-K染色、醋酸洋红染色、DAPI染色和石蜡切片法对其花药形态特征及小孢子形成和发育过程进行细胞学观察。结果表明:Ju87B1-706A具有黑麦1RS的特异扩增条带(1 500bp),但缺少1BS的特异扩增条带(220bp),与其在A-PAGE结果的ω区与黑麦特异蛋白谱带的结果相对应,从而说明牡山羊草细胞质雄性不育小麦Ju87B1-706A为1BL/1RS雄性不育小麦类型;I2-K染色说明Ju87B1-706A的败育类型为典败和染败;Ju87B1-706A能正常进行减数分裂形成小孢子,到单核晚期时能形成正常的核但细胞皱缩,二核期细胞形态不规则能形成正常的精核但有些营养核不清晰,三核期精核呈圆形不能形成梭形的精核并发生部分空胞化;其单核晚期花药中绒毡层的延迟解离以及二核期三核期细胞团侵入药室造成小孢子败育,从而推测单核晚期是其雄性不育发生的关键时期,可能与绒毡层异常有关。     

山羊草属植物醇溶蛋白的遗传多样性分析

利用APAGE技术对山羊草属中6个物种30份材料的醇溶蛋白进行了分析,共出现14种醇溶蛋白APAGE谱带类型和67条相对迁移率不同的谱带,其中,每份材料可分离出10~22条带,所有67条谱带均具有多态性。同一物种内的谱带类型为1~4种,种间没有出现相同的带型。种内各材料间谱带类型可完全相同,带型间的最大相似系数为0.941,而种间最大相似系数则为0.606。     

Genetic analysis of resistance to <Emphasis Type="Italic">soil-borne wheat mosaic virus</Emphasis> derived from <Emphasis Type="Italic">Aegilops tauschii</Emphasis>

Genetic Analysis of Resistance to Soil-Borne Wheat Mosaic Virus Derived from Aegilops tauschii. Euphytica. Soil-Borne Wheat Mosaic Virus (SBWMV), vectored by the soil inhabiting organism Polymyxa graminis, causes damage to wheat (Triticum aestivum) yields in most of the wheat growing regions of the world. In localized fields, the entire crop may be lost to the virus. Although many winter wheat cultivars contain resistance to SBWMV, the inheritance of resistance is poorly understood. A linkage analysis of a segregating recombinant inbred line population from the cross KS96WGRC40 × Wichita identified a gene of major effect conferring resistance to SBWMV in the germplasm KS96WGRC40. The SBWMV resistance gene within KS96WGRC40 was derived from accession TA2397 of Aegilops taushcii and is located on the long arm of chromosome 5D, flanked by microsatellite markers Xcfd10 and Xbarc144. The relationship of this locus with a previously identified QTL for SBWMV resistance and the Sbm1 gene conferring resistance to soil-borne cereal mosaic virus is not known, but suggests that a gene on 5DL conferring resistance to both viruses may be present in T. aestivum, as well as the D-genome donor Ae. tauschii.     

Identification and isolation of a new x-type HMW glutenin subunit 1Dx1.6t gene from Aegilops tauschii

A new x-type HMW glutenin subunit, designated as 1Dx1.6^t from Aegilops tauschii was identified and characterized by SDS-PAGE and MALDI-TOF-MS. This subunit is located between 1Dx2 and 1Dx1.5^t and possesses a molecular mass ( M _r) of 88565.8 Da. Its complete coding sequence was amplified via allele-specific PCR (AS-PCR), and the amplified product was cloned and sequenced. The authenticity of the cloned 1Dx1.6 ^t gene was confirmed by successful expression of its open reading frame in Escherichia coli. The molecular characterization of 1Dx1.6 ^t gene showed that its coding region consisted of 2541 bp encoding a polypeptide of 845 amino acid residues. Sequence comparison to previously characterized 1Dx1.5^t subunit which is related to good dough quality of bread wheat indicated that the 1Dx1.6^t subunit displayed high homology, but possesses 14 residue substitutions and a nonapeptide insertion. A total of 12 single-nucleotide polymorphisms (1 per 212 bp) was identified in the 1Dx1.6 ^t allele (11 in repetitive domain and 1 in the C-terminal domain), which could facilitate the design of AS-PCR markers.     

节节麦高分子量谷蛋白Dx5~t+Dy12~t亚基组合中Dy12~t亚基的序列测定与分析

为了认识节节麦5t+12t亚基品质表现突出的分子基础,利用SDS-PAGE分析研究了该亚基组合中12t亚基的电泳迁移率并克隆和测序了该亚基基因。结果表明,该12t亚基在SDS-PAGE上的电泳迁移率与普通小麦中的Dy12具有一致的电泳迁移率,但与Dy10的电泳迁移率差异明显。而氨基酸序列比较结果显示,12t亚基的分子序列与Dy10的相似程度非常高,二者仅存在4个氨基酸的替换,而它与Dy12的分子序列存在较大的差异,不但包括12个氨基酸的替换,同时包括2个六肽氨基酸和另外4个氨基酸部位的插入和缺失变化。本研究结果表明,节节麦高分子量谷蛋白Dx5t+Dy12t亚基赋予小麦优良加工品质的主要原因可能与12t亚基与小麦Dy10非常相似,导致这一亚基组合更倾向与Dx5+Dy10有一定关系。