基因工程在油菜遗传改良中的应用

报道了基因工程在油菜品质改良、抗除草剂、抗病虫及油采杂种优势利用中的应用进展。     

主要麻类作物的ITS序列分析与系统进化

比较主要麻类作物和测序植物间的ITS序列,可明确它们间系统位置和进化关系。本研究采用PCR扩增和搜索Gen Bank数据库,获得32份麻类作物和11份测序作物的核糖体内转录间隔区(internal transcribed spacers,ITS)序列,利用MEGE软件分析ITS长度、G+C含量与同源性百分比差异。结果表明,黄麻属、红麻属、苎麻属和亚麻属的ITS基本序列全长分别为963、939、658和686 bp;G+C含量分别为57.87%、58.03%、59.05%和53.75%。黄麻属变异区域集中在220~386 bp间,红麻属变异区域集中在2个区段(206~347 bp,599~713 bp),苎麻属ITS变异区域分布在4个区段(158~163 bp、193~199 bp、288~333 bp和681~688 bp),亚麻属ITS变异区域分布在5个区段(219~229bp、235~240 bp、427~432 bp、468~484 bp和588~594 bp)。系统位置分析表明,红麻属与棉花亲缘关系最近,黄麻与棉花亲缘关系较近;亚麻与苎麻各为一小支。系统位置分析与传统的植物分类结果较一致。研究主要麻类作物比较基因组学时,红麻、黄麻可参考棉花,苎麻可参考杨树或蓖麻。推测红麻属的进化时间约为33.7百万年前(million years ago,MYA),黄麻属约为65.3MYA,苎麻属约为67.5MYA,亚麻属约为90.5MYA。主要麻类作物进化时间越久,同属不同种之间ITS变异区段越多。     

青贮玉米育种现状和遗传改良对策

青贮玉米是我国玉米生产所需的特用玉米,在畜牧业发展中起到重要作用。畜牧业不能很好地利用玉米茎叶等部分,秸秆焚烧造成严重的环境污染,青贮玉米推广受到广泛关注。研究分析我国国审青贮玉米品种的杂种优势群,温热I群×瑞德黄、瑞德黄×热带种质杂优模式具有代表性。归为温热I群的有16个系,13个品种达品质一级标准。生物产量是青贮玉米遗传改良的重要目标,以青贮专用型为主是育种的方向。拓宽种质资源遗传改良基础是青贮玉米育种的重要手段。采用以单交种为主的组配方式完善品种试验程序,有利于遗传改良取得突破。     

藜麦遗传改良现状与发展方向

藜麦育种研究是以改良和优化藜麦的品种,实现产量、品质和抗逆性的提高为目标,通过深入研究藜麦的遗传背景和基础,了解藜麦的遗传多样性,建立丰富的遗传资源库,为未来的育种工作提供更多的遗传材料。传统育种方法结合现代分子标记辅助选择和基因组选择技术等手段可以加速藜麦的遗传改良进程,转基因技术也为提高藜麦的抗病虫能力提供了新途径。然而,藜麦育种仍面临一些挑战,包括遗传改良速度较慢、抗病和抗虫育种仍面临挑战,以及品质改良有待提高。因此,加强研究合作、拓宽遗传资源来源、加强品种改良和开发适应性更强的品种等是未来藜麦育种研究的重点和方向。通过科研创新和广泛合作,藜麦育种的发展将会不断推进,为解决全球粮食安全和可持续发展作出贡献。     

CRISPR/Cas9系统及其在粮油作物遗传改良中的研究进展

CRISPR是细菌或古生菌对入侵到体内的病毒,通过核酸特异性识别、Cas9蛋白酶切割产生的一种天然免疫系统.基于CRISPR/Cas9系统的基因组编辑技术,通过sgRNA介导和Cas9蛋白切割实现对靶基因的定点编辑.因其操作简便、编辑效率高、适用范围广的特点,迅速成为研究植物、动物、微生物基因功能的重要手段.同时,随着...     

稻米淀粉品质遗传与改良研究进展

本文介绍了稻米淀粉品质性状的含义和主要内容,较全面地总结了直链淀粉含量、糊化温度、胶稠度、RVA谱、支链淀粉结构、淀粉膨胀体积以及淀粉凝胶的质构和老化特性等性状的遗传研究进展.总结了淀粉品质与其它品质性状与农艺性状的遗传相关性,环境条件(灌浆结实期气温)及基因型×环境互作效应对稻米淀粉品质的影响,及分子辅助选择与基因工程技术改良稻米淀粉品质的研究进展.今后淀品质研究应集中在淀粉品质相关性状形成的基因网络解析、淀粉基因分子标记挖掘、淀粉品质的多基因聚合育种及淀粉品质分子设计的数据库建设.通过应用基础研究以及相关技术集成,特别是分子设计(聚合)育种技术的实践,有望培育出淀粉品质符合市场要求的优良品种.     

棉花抗逆遗传改良技术与应用

病害、干旱、盐碱等逆境胁迫是棉花生产实现高产稳产的主要影响因素,利用传统育种和现代生物技术对现有棉花育种资源的抗逆性状进行遗传改良是实现高产、优质、多抗育种目标,培育突破性棉花新品种的有效途径。综述了中国农业科学院棉花研究所棉花抗逆遗传改良团队近年来在棉花抗逆育种新材料创制、抗逆育种关键技术研发与新品种培育方面的最新进展,并且提出了未来我国棉花抗逆遗传改良的研究方向。     

安徽省历年油菜审定品种主要性状遗传改良

通过对1983~2012年安徽省审定的70份油菜品种的品质和主要经济性状演变规律及其与产量的相关性进行研究,发现育成年代与生育期、一次有效分枝、单株角果数及产量间具有极显著线性回归关系,与株高、千粒重、硫普和芥酸具有显著线性回归关系;进一步分析发现,经过30年的品种改良,产量、单株角果数、千粒重、生育期、株高和一次有效分枝数分别增加了81.22%、97.56%、11.90%、10.08%、10.03%和29.42%。而品种育成年代与每果粒数和含油量无显著线性关系,表明这些年育成品种在每角粒数与含油量方面未有明显改良。6个经济性状和产量的相关性研究表明单株角果数与一次有效分枝数、产量均表现极显著正偏相关,偏相关系数分别为0.5626和0.5190,千粒重和生育期表现显著正偏相关(0.2588)。数据分析暗示品种进一步改良有可能通过提高每果粒数和(或)含油量实现。     

玉米Suwan种质改良过程中的关键基因组区段发掘

玉米Suwan种质抗性好、适应性强、籽粒品质优,在现代育种尤其是南方玉米育种中具有不可替代的作用。明确Suwan种质优良特性在改良过程中的遗传机制对我国南方玉米生态区的玉米生产具有重要意义。本研究以Suwan1(Suwan1C10)及其衍生群体(苏兰1号C0)不同改良世代为材料,利用包含5.6万个SNP标记的MaizeSNP50芯片对供试群体进行基因型鉴定。遗传分析发现:Suwan 1群体不同改良世代间的基因组差异片段较少,仅出现5个,其中4个出现在第11轮改良世代(Suwan 1 C11), 1个出现在第15轮改良世代(Suwan 1 C15);苏兰1号不同改良世代间的基因组差异片段相对较多,共有18个,其中8个在不同改良世代间稳定遗传; Suwan种质改良形成苏兰1号群体的过程中,共获得43个Lancaster特异性遗传片段,其中35个在苏兰1号不同改良世代间稳定遗传。全基因组关联分析共鉴定出16个与穗行数显著关联的QTN,分别位于第2、第3、第5、第6、第7、第8、第9染色体上,其中SYN25713和SYN36577位于苏兰1号群体的Lancaster特异性遗传片段内;共检测到13个控制穗长相关的QTN,分别位于第1、第2、第5、第7、第8、第9染色体上,其中PZE-105143697位于苏兰1号群体的Lancaster特异性遗传片段内。该结果为后续全基因组关联研究和分子标记辅助选择等提供了重要的理论依据。     

Restriction fragment length polymorphisms and genetic improvement of agricultural species

Evidence is accumulating demonstrating the ubiquity and abundance of a new class of genetic markers, restriction fragment length polymorphisms (RFLPs). These markers should allow the genetic map of agricultural species to be saturated in the near future. This holds great promise for useful applications, including: protection of breeder's rights, and more effective means for the characterization and manipulation of individual genetic loci affecting traits of economic importance.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No 768-E, 1985 series. Supported by the U.S.-Israel Agricultural Research and Development Fund (BARD).     

能源甜高粱遗传改良研究进展

甜高粱是最有应用前景的再生能源作物之一,它的能源转换效率取决于植株总生物量和茎秆汁液含糖量的高低。探明决定甜高粱总生物量和茎秆汁液含糖量积累相关过程的生物学机制并开发相应分子标记,是选育生物能专用甜高粱品种的有效途径。本文从甜高粱糖分积累、遗传多样性研究、遗传图谱的构建、含糖量相关性状的定位及遗传工程研究等方面介绍了近年来甜高粱遗传研究进展。     

陆地棉纤维细度相关性状的遗传及相关性分析

 利用主基因与多基因混合遗传模型的P₁、P₂、F₁、F₂四世代联合分析方法,研究了棉花纤维细度相关性状的遗传,进一步明确了主基因存在的普遍性。同时,对麦克隆值密切相关的纤维线密度及成熟度比率进行了F₂、F_2:3家系的主基因 多基因单世代分析,初步判定线密度也存在一对主基因。性状间的遗传相关分析表明,麦克隆值及成熟度比率与整齐度分别呈极显著正相关和不相关,该两个性状与其它性状的相关性两个世代表现不一致;线密度与整齐度呈正相关,与伸长率呈极显著负相关,与长度、强度及衣分不相关。线密度与各性状的相关性要比麦克隆值和成熟度比率稳定,受环境影响小,有必要加强线密度的选择及深入研究。     

Evaluation of newly developed SSR markers and identification of quantitative trait loci for bast fibre cellulose in white jute (Corchorus capsularis)

Cellulose is one of the main chemical component of bast fibre in jute. However, quantitative trait loci (QTL) for bast fibre cellulose content remains elusive. In this study, we identified 846 new SSR markers from 70,792 unigenes in the NCBI and validated them in a panel of 24 diverse jute accessions. Of 846 SSRs, 748 (88.41%) were successfully amplified, and 585 (69.14%) showed polymorphisms, implying that these are high‐quality SSRs. Furthermore, 585 SSRs along with 5,074 polymorphic SLAF (specific locus amplified fragment) and 173 InDel markers were used to reconstruct a high‐dense linkage map in a recombinant inbred population with 104 F₈ lines. Totally, 835 markers were successfully mapped to a whole length of 604.5 cM with a mean distance of 2.84 cM between adjacent markers. Furthermore, five QTLs for bast fibre cellulose were identified. One major QTL (qBFC1‐1) was stable in 2 years and explained average phenotypic variance with 14.34%. These results may be useful for developing enhanced bast fibre quality in white jute through marker‐assisted selection (MAS) breeding.     

A comparison of bulk testing and direct-line testing in self-fertilizing crops

Summary Computer simulation techniques were used to compare the efficiency of bulk-yield testing with direct-line yield testing. Bulk testing was almost always more efficient than direct-line testing for a wide range of values for population parameters. The differences between the two methods were smaller when the among-bulk heritability was low, the within-bulk genetic variance was high relative to the among-bulk variance, the variance of the within-bulk genetic variance was high, and the correlation between bulk means and within-bulk genetic variances was highly negative.With the direct-line testing method, discarding lines with low means after the first year of testing was always more efficient than retaining all lines for 2 years. Selection of 25% of the lines was slightly more efficient than selection of 50%. In general, it was better to evaluate more crosses and less lines per cross with the direct-line testing procedure.     

大棚内麻地膜覆盖栽培下辣椒的营养生长和产量研究

为明确大棚内麻地膜覆盖对辣椒营养生长的影响,测量不同覆盖处理下辣椒主要营养生长时期的株高和分枝级数,开花初期的开花率,结果初期的结果率,结果期辣椒的总产量,拔棵期辣椒的营养器官干物质积累及养分积累。结果表明,白色麻地膜覆盖下辣椒的株高一直最高,除5月2日取样外,其余时期分枝级数也最多;白色麻地膜覆盖下辣椒营养器官干物质积累和养分积累最高;白色麻地膜覆盖辣椒开花率比无覆盖高53.34%,结果率同样为白色麻地膜覆盖最高;白色麻地膜覆盖产量比无覆盖高31.20%。研究表明,麻地膜覆盖促进辣椒营养生长,同时没有对生殖生长造成不利影响,可以增加辣椒产量。     

The potential of gene technology and genome analysis for cool season food legume crops: theory and practice

The potential of plant gene technology encompasses a multitude of different techniques ranging from the isolation of useful genes, their characterization and in vitro manipulation to the reintroduction of the modified constructs into target plants, where they are expressed at a rate that alters the phenotype of the plants. Genome analysis, on the other hand, aims at characterizing the genome architecture and function(s).Plant gene technology has catalyzed progress in plant breeding, as will be exemplified by a few examples, but has not yet been applied to food legume improvement on a large scale. Genome analysis, however, has a series of practical implications, as is illustrated by the successful introduction of DNA fingerprint and PCR fingerprint techniques to chickpea (Cicer arietinum L.) breeding and Ascochyta rabiei pathotyping. The present overview addresses both areas of plant molecular biology to illustrate their potential for food legume breeding.     

主要禾谷类作物糯质基因Waxy的系统进化及表达分析

糯性是农作物的一项重要农艺性状。有效控制农作物糯性的高低有助于选育出糯性适当的高品质谷物。糯性主要受Waxy基因控制,主要由于Waxy的缺失而引起籽粒支链淀粉含量升高所致。Waxy基因具有较高的保守性,在主要农作物的自然选择及人工选择的过程中,Waxy表达水平不同的种质材料被固定下来,并用于农作物新品种选育。本研究基于当前关于糯质基因Waxy的研究现状,系统分析了糯质玉米、不同倍型小麦中Waxy基因的拷贝数、变异特征及系统进化关系,期望进一步获得Waxy基因在农作物遗传改良中稳定糯性的调控机制。本研究也对如何利用基因编辑技术改良农作物的糯性进行了探讨。     

Wide somatic hybrids of Citrus with its related genera and their potential in genetic improvement

Citrus wild relatives are an untapped germplasm reservoir, which possesses many elite resistance traits. Genetic introgression into Citrus by conventional methods has been greatly hindered by polyembryony, pollen / ovule sterility, sexual / graft incompatibility, long juvenility etc. Somatic hybridization via protoplast fusion may make it possible to transfer genes from wild relatives to Citrus. To date, more than sixty sexually compatible or incompatible intergeneric somatic hybrids between Citrus and its various related wild genera have been produced by PEG - orelectrically - induced fusion. These wide somatic hybrids were identified by morphology, cytology, isozyme, RAPD and RFLP analyses. Genetic variation or recombination was also revealed in some of them. Several sexually compatible combinations have flowered and set fruits. The agronomic performance of these wide somatic hybrids is diverse, and the current results are not conclusive. Somatic hybrids are being tested as rootstocks. The prospects of wide somatic hybridization of Citrus with its wild relatives are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.