节节麦与野生燕麦杂种F2研究

节节麦Aegilops tauschii(Coss.)Sch.2n=2x=14与通北野燕麦Avena Fatua L.2n=6x=42杂交,F_1代为双二倍体,2n=56。F_2代主要群体为双二倍体,2n=56。有一部分为2n=27Ⅱ,也出现一部分为2n=54,有2～4个单价体。出现个别的7倍体类型,穗型属斯卑尔脱小麦型,结实率极低,不足0.5%,籽粒饱满,100粒重4.75克。PMC染色体构图为2n=21Ⅱ 7Ⅰ。出现极少数的5倍体类型,株型和穗型类似节燕双二倍体,但结实率极低,染色体构图为2n=14Ⅱ 21Ⅰ。并出现普通小麦型,共2株,株高78.1和81.5厘米,籽粒基本饱满,100粒重4.34克和3.92克。PMC染色体构图为2n=21Ⅱ。     

野生二粒小麦与野生燕麦族间杂交研究——Ⅱ、杂种 F_2成株期形态学和细胞学研究

野生二粒小麦与野生燕麦杂交F_2共61株,其中抽穗前(?)亡和黄化未能抽穗的共21株。分离出野生二粒小麦型、硬粒小麦型、斯卑尔脱小麦型、燕麦型和普通小麦型。野生二粒小麦型结实率11.2～63.5%,PMC染色体数为27～36。硬粒小麦型结实正常,PMC染色体数为2n=14″。斯卑尔脱小麦型结实率2.7～43.4%,PMC染色体数为37～50。燕麦型结实基本正常,PMC染色体数为41～43,出现1～2个单价体。普通小麦型的护颖包裹籽粒较松,不断穗节,容易脱粒,染色体数为39～45,结实率1.2～68.2%。杂种F_2不同类型植株的PMC染色体数为27～50,每株能抽穗扬花的植株都能结实,结实率1.2～92.3%。杂种F_2的小麦型中有一部分植株的芒长在外颖背上,表现出燕麦族的分类特征性状。     

黑小麦与通北野燕麦杂交研究

黑小麦(2n=42)与通北野燕麦(Avena fatua L.2n=6x=42)杂交成功。F_1代出现两种类型,一种为具有燕麦复总状花序相近穗型的类型,共2株,有一部分小穗有枝梗,小穗着生处为园形膨大的结节。经PMC镜检,染色体构图为2n=18Ⅱ 6Ⅰ,全部不结实。另一种类型具有与黑小麦相近的穗型,共5株,部分结实,经PMC镜检表明,染色体构图为2n=20Ⅱ 2Ⅰ,2n=19Ⅱ 3Ⅰ,和2n=19Ⅱ 4Ⅰ。籽粒均不饱满。     

节节麦与野燕麦8倍体杂种核型分析

节节麦(Aegilops tauschii(Coss.)Sch.2n=2x=14)与通北野燕麦(Avena fatua L.2n=6x=42)杂交,F_1自然加倍成8倍体,8倍体播成的F_2代,遗传性基本一致,PMC镜检表明,染色体数为2n=28Ⅱ。用F_2所结的种子进行根尖细胞核型分析,结果发现8倍体中包含有全套的节节麦和野燕麦的染色体。节节麦中有1对随体染色体.2对近中部着丝点染色体,4对中部着丝点染色体。野燕麦有3对随体染色体,5对近端着丝点染色体,8对近中部着丝点染色体,5对中部着丝点染色体。而节节麦与野燕麦8倍体杂种,有4对随体染色体,5对近端着丝点染色体.10对近中部着丝点染色体,9对中部着丝点染色体。核型分析结果表明,节节麦与野燕麦杂交合成的8倍体,是节节麦与野燕麦的双二倍体。     

野生二粒小麦与野生燕麦远缘杂交研究

野生二粒小麦(Triticum dicoccoides Con,2n=4X=28)与野生燕麦(Avena fatua L、2N=6X=42)直接杂交成功。F_1代优势强,主穗和一、二次分蘖穗基本不结实,愈到以后分蘖结实率愈高,所结种子饱满和基本饱满,F_1的穗子不断节,颖壳包裹籽粒不太紧。F_1花粉母细胞镜检表明,野生二粒小麦的2组染色体与野生燕麦3组染色体中的2组基本配对。杂种F_2分离出5株燕麦型植株,经过氧化物同工酶研究表明,它们具有野生燕麦的特征谱带,又具有野生二粒小麦的特征谱带,大部分小麦型植株均具有野生燕麦谱带。     

小麦种子繁殖与节节麦的防治

近年来节节麦对小麦生产的危害呈现增长趋势,种子生产流通环节也成为节节麦扩散的一种主要途径。加强种子繁育各环节的防治与管控,是减少扩散、降低节节麦发展危害的有效途径。在小麦种子繁育过程中,加强繁种基地的严选、原始繁材的把控、扩繁过程中的防控、加工储存流通等环节的检验,是提高种子质量、断绝种子生产流通中节节麦扩散的主要方法。田间综合防治技术结合优质良种的持续使用,能够切断节节麦的传播,减少其对小麦生产所造成的危害。     

麦田恶性杂草节节麦的发生与防治

介绍了节节麦的发生特点及发生原因,提出包括严控传播繁殖途径、提高田间麦苗竞争力、改善耕作方式在内的农业防治措施,并提出相关化学防治方法。     

小麦培养细胞与燕麦叶肉细胞原生质体的电融合

燕麦(Avena sativa L.)具有许多农业上重要的性状.但小麦和燕麦分类上属不同族,亲缘关系较远,有性杂交十分困难.近年来,在双子叶模式植物上建立的只转移供体亲本部分遗传物质的原生质体不对称融合技木为将燕麦有益性状导入小麦提供了可能.实现体细胞杂种定向不对称的途径有两种:一是利用细胞周期停滞在间期的叶肉细胞原生质体为供体亲本与作为受体亲本的培养细胞原生质体融合,由于二者分裂速度的差异,使前者染色体大量片段化     

Aegilops kotschyi and Aegilops tauschii as sources for higher levels of grain Iron and Zinc

Micronutrient malnutrition affects a very large proportion of the world's population. For combating micronutrient malnutrition, biofortification through genetic manipulation has been proposed as an alternative to traditional fortification for increasing the bioavailable nutrient content of food crops. Wheat, being a staple food for a large section of the world's population, is targeted for increasing the Fe and Zn content in the grains. The cultivated germplasm of wheat does not have sufficient variability for grain Fe and Zn content but the wild species of wheat do show wider variation for grain micronutrient density. The analysis of Aegilops kotschyi and A. tauschii for Fe and Zn content in the grains using an atomic absorption spectrophotometer (AAS) indicated that the S and D genome species accumulate significantly higher iron and zinc in the grains than the cultivated wheats. One of the CIMMYT synthetics also had significantly higher Fe and Zn in the grains as compared with the cultivated wheats. Aegilops kotschyi as a promising source for Fe and Zn, is reported for the first time. A systematic programme to identify and utilize the additional sources for high Fe and Zn has been initiated.     

不同小麦品种对节节麦的化感作用

本文采用培养皿琼脂共培法,通过研究不同小麦品种对节节麦根长、芽长、根干重、芽干重等生长指标的影响,评价不同小麦品种对节节麦的化感作用差异,以期筛选出对节节麦化感作用较强的小麦品种,为节节麦综合防治提供潜在可行途径。研究结果表明,在测定的46个小麦品种中,不同小麦品种对节节麦根长、芽长、根干重、芽干重的化感作用均存在显著差异;且小麦对节节麦根的化感作用大于对芽的化感作用。以RI值作为化感作用指标,并运用聚类分析,将46个小麦品种按化感能力的强弱分为强、中、弱3个类群,筛选出‘山农15’、‘济麦23’、‘泰科麦30’、‘FC009’、‘良星66’、‘众信7503’等6个品种对节节麦具有较强化感作用。     

波斯小麦×节节麦杂种F_1直接形成双二倍体的细胞遗传学研究

波斯小麦(Triticum carthlicum,AABB)与节节麦(Aegilops tauschii,DD)杂交,杂种 F_1出现可育性。不同组合的自交结实率21.25—39.72%。细胞学研究表明,可育性是由于杂种 F_1通过两种途径形成了未减数配子:第一,一部分花粉母细胞第一次分裂消失,只发生第二次分裂。即21条染色体集中到赤道面上之后,姊妹染色单体均等分离并移向     

Cytology and Fertility of Hybrids and Amphiploids between Aegilops caudata L. ×Triticum turgidum (L.) Thell

Interspecific hybrids and amphiploids between Aegilops caudata L. (2n = 2x = 14, CC) and Triticum turgidum (L.) Thell. conv. durum Desf M. K. (2n = 4x = 28, AABB) were produced. Such hybrids can be used to introduce desirable traits such as disease resistance into cultivated durum wheats. One of the durum parents was a ph I mutation of the cv. ‘Cappelli’ used for testing the possibility of direct introduction of alien variation into cultivated species. The amphiploids were obtained both through colchicine chromosome doubling and as natural non-reductional mciosis products. In both hybrids and amphiploids, meiotic pairing and fertility were studied. Hybrids showed varying degrees of pairing and, in addition to the one involving the ph 1 mutant, one high pairing hybrid was found (Ae. caudata× cv. ‘Capinera’). Cytological examination of microsporogenesis in amphiploids revealed a high frequency of bivalent formation. Fertility proved to be a very variable character since some of the amphiploids were almost completely sterile. The use of amphiploids in breeding programmes is discussed in relation to meiotic and fertility data.     

Inheritance in synthetic hexaploid wheat ‘RSP’ of sprouting tolerance derived from Aegilops tauschii Cosson

An artificial amphiploid ‘RSP’ (2n = 42, AABBDD) between tetraploid landrace Ailanmai (Triticum turgidum L., 2 = 28, AABB) and Aegilops tauschii (DD, 2n = 14) expressed high tolerance to preharvest sprouting which derived from Aegilops tauschii. To determine the inheritance of sprouting tolerance in ‘RSP’, it was crossed with six cultivars which vary in susceptibility to preharvest sprouting. Preharvest sprouting tolerance was assessed on F₂ plants using germination towels. Preharvest sprouting tolerance was inherited as a recessive trait which was controlled by one gene. This revised version was published online in July 2006 with corrections to the Cover Date.     

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.     

普通小麦及近缘粗山羊草α-醇溶蛋白基因的克降、定位与进化分析

通过特异PCR引物设计,从普通小麦品种(豫麦34和烟农19)和粗山羊草(T9、T197、T48、T176和T17)中扩增、克隆了7个新的α-醇溶蛋白基因,分别命名为Gli-YM34、Gli-YN19、Gli-T9、Gli-T197、Gli-T48、Gli-T176和Gli-T17,基因序列长度为846~891 bp,编码282~297个氨基酸残基,都具有α-醇溶蛋白的典型结构特点。其中Gli-YM34和Gli-YN19基因推导的醇溶蛋白都含有一个额外的半胱氨酸残基,可能对面筋品质有正向作用。根据α-醇溶蛋白氨基酸序列所具有的4种T细胞抗原表位和多聚谷氨酰胺重复区的平均长度以及中国春缺体四体分析,将来自普通小麦品种的Gli-YM34和Gli-YN19基因定位在6D染色体上的Gli-D2位点,而且Gli-YM34和Gli-YN19与来自粗山羊草的α-醇溶蛋白基因具有很高的序列相似性,进一步证明粗山羊草是普通小麦D基因组的供体。在克隆的4个典型α-醇溶蛋白基因中检测到21个SNP和1个9 bp的缺失。系统进化分析表明,α-醇溶蛋白基因与低分子量谷蛋白亚基基因关系较近,在大约43.69百万年时分化,与ω-醇溶蛋白和HMW-GS基因亲缘关系较远,它们的分化时间大约为79.39百万年。     

山羊草谷胱甘肽S-转移酶基因家族鉴定及表达分析

谷胱甘肽S-转移酶是一种多功能蛋白酶,在植物体内参与干旱、盐、低温、重金属等多种非生物胁迫的调节;山羊草是普通小麦D染色体组的供体物种,深入挖掘山羊草中GST基因,对进一步分析六倍体小麦GST基因的功能具有重要意义。本研究利用信息生物学手段,在山羊草中共发现114条GST基因序列,分属于6个亚族;基因复制分析发现共4对基因发生了基因复制,且均为纯化选择;采用荧光定量PCR对部分GST基因在非生物胁迫下的表达分析发现,8个GST基因在响应干旱和盐胁迫时,主要在根部显著上调表达,3个GST基因在响应低温胁迫时,在根和叶中均显著上调表达,说明山羊草中的GST基因在应答非生物胁迫时,在不同组织中的表达存在着差异。