甜瓜PI414723抗霜霉病基因SSR分子标记

为了研究野生甜瓜PI414723抗性遗传规律,找到与抗病基因连锁的分子标记,并对抗病基因进行定位。以野生甜瓜PI414723和新疆哈密瓜农家品种卡拉克赛为材料构建BCr、BCs和F2,苗期接种甜瓜霜霉病进行抗性鉴定、统计分析,基于ICu GI已构建遗传连锁图谱,应用集团分离法和1 090对甜瓜SSR引物进行连锁遗传分析。结果表明:PI414723对霜霉病的抗性由隐性单基因控制,引物DM0231扩增出的多态性条带与抗病基因表现连锁关系,该多态性片段大小为226 bp,遗传连锁距离为2.67 c M,并将抗病基因定位在LG9上。DM0231可作为甜瓜抗霜霉病分子育种的分子标记,也为进一步对抗霜霉病基因精细定位奠定了基础。     

甜瓜抗霜霉病基因SSR分子标记

为了研究甜瓜抗霜霉病资源T115抗性遗传规律,找到与抗病基因连锁的分子标记,并对抗病基因进行定位。以抗病资源T115和感病哈密瓜农家品种SP红心脆、F1、BCr、BCs、F2为材料,苗期接种甜瓜霜霉病进行抗性鉴定,基于ICu GI已构建遗传连锁图谱,应用集团分离法和1 090对甜瓜SSR引物进行连锁遗传分析。结果表明,T115对霜霉病的抗性属显性单基因控制,引物DM0073扩增出的特异性片段与抗病基因表现连锁关系,该片段大小为120 bp,与抗病基因遗传连锁距离为3.6 c M,并将抗病基因定位在LG1上。DM0073可作为甜瓜抗霜霉病分子育种的分子标记。     

大豆抗病分子标记的研究进展

大豆（Glycine max L.）病害是影响大豆产量和品质的重要因素之一,随着大豆全基因组序列的公布,以SNP为代表的新一代分子标记技术使大豆抗病分子标记辅助育种得以快速发展。本文综述了2010年以来研究者们对大豆抗性基因的定位方法、抗病基因的定位、候选基因的筛选及鉴定等所取得的新进展,并结合当前大豆抗病分子标记的现状提出了新的发展方向,为进一步探究相关抗病基因的功能及分子育种提供理论参考。     

性状相关的分子标记在甘蔗分子育种中的应用研究

分子设计育种在农作物品种改良中发挥了重要作用,但由于甘蔗基因组庞大且高度杂合,染色体呈非整倍性,导致其性状相关的分子标记辅助育种进展十分缓慢。为加快甘蔗育种进程,提高其育种效率和准确性,简述了甘蔗分子标记辅助育种现状及其瓶颈,并总结了应用于甘蔗的分子标记种类及其问题,阐明分子标记在甘蔗遗传连锁图谱构建中的作用,进而从甘蔗产量和糖分性状相关QTL的定位、主要抗病基因（抗褐锈病基因、抗黑穗病和抗黄斑病基因）的定位及其在抗病分子育种上的应用,以及关联分析方法在甘蔗重要性状研究中的应用等方面对性状相关的分子标记进行综述。最后对甘蔗重要性状相关分子标记辅助育种的机遇和挑战进行了展望,为甘蔗分子育种的深入研究提供理论依据。     

小麦白粉病抗病基因分子标记开发及应用研究进展

选育和利用抗病品种是防治白粉病最经济、有效、安全的措施,优异抗白粉病基因资源的挖掘及其紧密连锁分子标记的开发是开展抗白粉病分子标记育种的基础。目前,国内外已命名了分布于16条染色体上的39个位点共55个白粉病抗病基因,其中30个已开发出分子标记,另外还发现数个与成株期抗性相关的数量性状位点。本文综述了国内外小麦白粉病抗病基因的定位、来源、分子标记开发、克隆,以及白粉病抗病基因的分子标记育种的最新研究进展,并分析了当前小麦抗白粉病育种存在的主要问题及解决建议。     

马铃薯品质性状分子育种研究进展

较为简要地叙述了目前马铃薯品质性状分子育种研究进展状况,对马铃薯炸片颜色基因、高蛋白质基因两品质性状的分子标记研究进展以及利用基因工程技术提高马铃薯淀粉含量、降低还原糖含量、提高蛋白质含量、选育优质品种等方面的进展情况进行了描述,并对利用分子育种技术改良马铃薯品质研究中分子标记、基因工程技术上存在的问题作以探讨,为今后开展马铃薯分子育种研究奠定基础,同时对利用分子育种技术改良马铃薯品质前景进行了展望。     

玉米抗病基因一致性图谱的构建

发掘和精细定位玉米抗病基因是构建玉米抗病分子育种技术体系的重要基础。利用生物信息学手段,整理文献和玉米基因组数据库中已有的抗病基因定位的信息,借助高密度玉米分子标记连锁图谱IBM2 2005 neighbors,通过染色体映射的方法,绘制了玉米抗病基因的一致性图谱。结果显示,在试验涉及到的14种主要玉米病害的78个抗病主基因或QTL之中,抗病基因在各条染色体上呈不均匀分布,第3、第6、第10染色体上的主效抗病基因较多,第5和第7染色体上的抗病基因较少,且抗病基因呈簇集分布。研究结果为进一步发掘和鉴定玉米抗病基因和建立玉米抗病分子标记辅助育种技术体系奠定了基础。     

分子标记聚合育种在毕节地区马铃薯抗病品种选育中的应用初探

简要阐述了分子标记辅助选择在作物遗传育种中的优势.结合毕节地区马铃薯育种实际,对毕节地区采用分子标记辅助选择技术开展马铃薯抗病基因聚合育种的重要性、可行性进行了分析,并对毕节地区今后的马铃薯育种工作提出了相应建议.     

甜瓜遗传图谱与基因定位研究进展

甜瓜是重要的葫芦科蔬菜作物之一,其遗传育种学广受研究者的关注。高密度分子遗传图谱有助于提高甜瓜的育种水平,加快育种进程。自1996年第一张甜瓜分子遗传图谱报道后,AFLP等分子标记逐步被应用于甜瓜分子遗传图谱的构建及基因定位。近年来,基因组测序技术发展迅速,全基因组重测序、简化基因组测序、转录组测序等技术逐渐被应用于构建覆盖全基因组的、更加饱和的甜瓜遗传连锁图谱。本研究着重对甜瓜分子遗传图谱、重要农艺性状基因定位研究进展进行了综述,以期为甜瓜生物学研究及分子改良提供理论参考。     

稻瘟病抗性基因在主要育种亲本中的分布研究

稻瘟病是由稻瘟病菌引起的具有广泛性和毁灭性的水稻病害。目前通过抗病亲本杂交聚合培育持久广谱的稻瘟病抗性品种是水稻稻瘟病防治最经济环保的途径,而利用分子标记辅助选择技术对水稻育种亲本抗性基因分布的研究是分子辅助聚合育种的基础。本研究以36个育种亲本为实验材料,进行苗瘟和穗颈瘟鉴定,结合特异性分子标记Pid3、Pita、Pikm、Pib、Piz,研究这些育种亲本的稻瘟病抗性基因的分布情况。同时,对恢复系材料蜀恢498的抗稻瘟病基因Pita和Pikm扩增测序并进行同源序列比对分析,初步在分子水平分析抗病基因与抗病表型的关系。     

甜瓜基因组学研究进展

甜瓜是一种世界性的园艺作物.随着现代生物技术的迅速发展,甜瓜基因组学研究越来越深入,国际葫芦科基因组计划也已经筹备完成即将启动.目前已构建有14张甜瓜遗传图谱,多个重要性状的分子标记及数量性状位点已找到并定位在图中,并开始在葫芦科作物之间进行比较基因组图谱方面的研究.已克隆出枯萎病抗性基因Fom-2,其它农艺性状基因的克隆工作也在陆续开展.本文在甜瓜遗传连锁图谱的构建、重要性状分子标记及OTL定位、比较基因组学及基因克隆等方面分别对其研究进展进行了探讨,以期为我国的甜瓜基因组学研究提供有益的参考.     

Breeding melon for resistance to Fusarium wilt: recent developments

Melon Fusarium wilt (MFW), caused by Fusarium oxysporum f. sp. melonis (Fom), is one of the most destructive diseases of melon (Cucumis melo L.). The development and deployment of resistant cultivars is generally considered to be the best approach to control MFW. Based on the host resistance genes associated with variants of this pathogen, Fom isolates were classified into four physiological races designated 0, 1, 2, and 1,2. Two dominant resistance genes, Fom-1 and Fom-2, control resistance to races 0 and 2, and 0 and 1, respectively. Fom isolates classified as race 1,2 are able to induce disease in melon lines carrying the above resistance genes. Many sources of resistance to Fom races 0, 1, and 2 have been reported. Partial resistance to race 1,2 controlled by polygenic recessive genes was only detected in a few Far Eastern melon accessions, except for the breeding line BIZ where complete resistance was described. Identification of DNA markers tightly linked to genes conferring resistance to Fom has immediate application in MFW resistance breeding programs. The Fom-2 gene has been cloned, and it encodes a protein with a nucleotide binding site (NBS) and leucine-rich repeats domain (LRR). Based on the sequence of this domain, some molecular markers linked to this gene were developed. Several DNA markers linked to Fom-1 have also been described. However, the usefulness of these markers was variety-dependent. Therefore, their combined use would be very useful in marker assisted selection for introducing resistance to Fom races 0 and 2 in melon. Recently, these markers were used for the positional cloning of this gene, which encoded a protein with a NBS–LRR domains that shows similarity to the toll and interleukin-1 receptores (TIR). Regarding Fom race 1,2, nine QTL were detected on five linkage groups by composite interval mapping. In this paper we review the current knowledge of MFW disease, and focus on genetic resistance to Fom and marker-assisted selection for resistance.     

Stability of seed oil quality traits in high and mid-oleic acid sunflower hybrids

Powdery mildew caused by Podosphaera xanthii is an important disease of melon, and race 2F is the predominant race in most areas of China. Resistance to P. xanthii race 2F in melon K7-1 was controlled by a dominant gene, designated Pm-2F, in a 106-member population of recombinant inbred lines derived from K7-1× susceptible K7-2. Using bulked segregant analysis with molecular markers, we have identified two polymorphic simple sequence repeats (SSR) to determine that Pm-2F is located on linkage group II. Comparative genomic analyses using mapped SSR markers and the cucumber genome sequence showed that the melon chromosomal region carrying Pm-2F is homologous to a 288,223 bp genomic region on cucumber chromosome (chr) 1. The SSR markers on chr 1 of cucumber, SSR02734, SSR02733 and CS27 were found linked with Pm-2F. Comparative mapping showed that two SSR markers (SSR02734 and CMBR8) flanked the Pm-2F locus and two nucleotide binding site-leucine-rich repeat resistance genes were identified in the collinear region of cucumber. A cleaved amplified polymorphic sequence (CAPS) marker was developed from the sequence of resistance genes and it delimits the genomic region carrying Pm-2F to 0.8 cM. The evaluation of 165 melon accessions and 13 race differential lines showed that the newly developed CAPS (CAPS-Dde I) marker can be used as a universal marker for effective marker assisted selection in melon powdery mildew resistance breeding. The putative resistance gene cluster provides a potential target site for further fine mapping and cloning of Pm-2F.     

小麦抗白粉病基因定位及分子标记辅助育种综述

小麦白粉病是小麦生产的主要病害之一。使用分子标记技术对抗白粉病基因进行定位,并进行标记辅助育种是防治该病的十分经济、有效的措施。到目前为止,小麦基因组中已定名抗白粉病基因33个,其中22个基因位点的28个抗白粉病基因找到了与之紧密连锁的分子标记,其中一些已经应用到标记辅助育种中。此文对小麦抗白粉病基因染色体定位、来源及其分子标记辅助育种研究现状进行了综述,针对存在的问题提出了解决的方法。     

Molecular mapping of powdery mildew resistance genes in wheat: A review

Powdery mildew, caused by Blumeria graminis f. sp. tritici (syn. Erysiphe graminis f. sp. tritici), is one of the most important diseases of common wheat (Triticum aestivum L.) worldwide. Molecular mapping and cloning of genes for resistance to powdery mildew in hexaploid wheat will facilitate the study of molecular mechanisms underlying resistance to powdery mildew diseases and help understand the structure and function of powdery mildew resistance genes, and permit marker-assisted selection in breeding programs. So far, 48 genes/alleles for resistance to powdery mildew at 32 loci have been identified and located on 16 different chromosomes, of which 21 resistance genes/alleles have been tagged by restriction fragment length polymorphisms (RFLPs), random-amplified polymorphic DNAs (RAPDs), amplified fragment length polymorphisms (AFLPs), sequence characterized amplified regions (SCARs), sequence-tagged sites (STS) or simple sequence repeats (SSRs). Several quantitative trait loci (QTLs) for adult plant resistance (APR) to powdery mildew have been associated with molecular markers. The detailed information on chromosomal location and molecular mapping of these genes has been reviewed. Isolation of powdery mildew resistance genes and development of valid molecular markers for pyramiding resistance genes in breeding programs is also discussed.     

Biotechnology and apple breeding in Japan

Apple is a fruit crop of significant economic importance, and breeders world wide continue to develop novel cultivars with improved characteristics. The lengthy juvenile period and the large field space required to grow apple populations have imposed major limitations on breeding. Various molecular biological techniques have been employed to make apple breeding easier. Transgenic technology has facilitated the development of apples with resistance to fungal or bacterial diseases, improved fruit quality, or root stocks with better rooting or dwarfing ability. DNA markers for disease resistance (scab, powdery mildew, fire-blight, Alternaria blotch) and fruit skin color have also been developed, and marker-assisted selection (MAS) has been employed in breeding programs. In the last decade, genomic sequences and chromosome maps of various cultivars have become available, allowing the development of large SNP arrays, enabling efficient QTL mapping and genomic selection (GS). In recent years, new technologies for genetic improvement, such as trans-grafting, virus vectors, and genome-editing, have emerged. Using these techniques, no foreign genes are present in the final product, and some of them show considerable promise for application to apple breeding.     

中国作物新基因发掘：现状、挑战与展望

中国作物新基因发掘是实现中国作物种质资源优势向基因资源优势转变和作物分子育种的基础。本文对中国近10年来水稻、小麦、玉米、大豆、棉花和油菜等主要作物基因发掘研究的进展进行了分析和评述。中国作物基因发掘也取得了一系列突破性进展：(1)创制出一批具有特色的基因发掘材料,包括基于中国作物遗传多样性的核心种质、基于优异资源的遗传分离群体和基于人工诱变的突变体等;(2)基因发掘技术和方法有所突破,尤其是在针对基因特点整合各种基因发掘技术、改进基因/QTL的生物统计算法等,提高了基因发掘的效率;(3)作物农艺性状的标记与基因定位已成为常规遗传研究方法,初步定位了一批抗病、抗逆、优质、养分高效、高产相关基因/QTL,其中,有500多个基因已精细定位;(4)以水稻为代表的作物基因克隆及功能研究在国际上受到瞩目,在主要作物中已克隆了300多个基因,其中,在目标作物中验证的基因数超过70个。在国际作物基因发掘高效化、规模化及实用化发展过程中,中国作物基因发掘也取得了重要进展。然而,中国作物基因发掘的数量和质量还远远不能满足作物分子育种的需求,与国际作物基因发掘也存在差距,具体表现为不同作物基因发掘研究进展不平衡、发掘基因的数量还相对有限、已发掘的基因中具有重大利用价值的基因不多。针对中国基因发掘面临的问题和世界各国以及跨国生物技术公司争夺基因的巨大挑战,作者提出了中国作物基因发掘应重点提高基因发掘效率,加强重要基因克隆及基因的价值评估,以生物产业发展需求为导向的基因发掘策略。     

Pathogenic diversity of Phytophthora sojae and breeding strategies to develop Phytophthora-resistant soybeans

Phytophthora stem and root rot, caused by Phytophthora sojae, is one of the most destructive diseases of soybean [Glycine max (L.) Merr.], and the incidence of this disease has been increasing in several soybean-producing areas around the world. This presents serious limitations for soybean production, with yield losses from 4 to 100%. The most effective method to reduce damage would be to grow Phytophthora-resistant soybean cultivars, and two types of host resistance have been described. Race-specific resistance conditioned by single dominant Rps (“resistance to Phytophthora sojae”) genes and quantitatively inherited partial resistance conferred by multiple genes could both provide protection from the pathogen. Molecular markers linked to Rps genes or quantitative trait loci (QTLs) underlying partial resistance have been identified on several molecular linkage groups corresponding to chromosomes. These markers can be used to screen for Phytophthora-resistant plants rapidly and efficiently, and to combine multiple resistance genes in the same background. This paper reviews what is currently known about pathogenic races of P. sojae in the USA and Japan, selection of sources of Rps genes or minor genes providing partial resistance, and the current state and future scope of breeding Phytophthora-resistant soybean cultivars.     

Powdery mildew resistance gene (<Emphasis Type="Italic">Pm</Emphasis>-<Emphasis Type="Italic">AN</Emphasis>) located in a segregation distortion region of melon LGV

Powdery mildew is one of the most important melon pathogens all over the world. So far, many genes conferring resistance to powdery mildew of melon have been described, but few of these have been finely mapped or cloned. Two F₂ populations derived from Ano2 × Hami413 and Ano2 × Queen were used to map the powdery mildew resistance gene by methods of Bulked Segregation Analysis (BSA), comparative genomics and Resistance Gene Analogues (RGA) mapping. It was found that the resistance to powdery mildew in Ano2 was conferred by a dominant gene, and the gene was named Pm-AN. The genetic analysis revealed that Pm-AN located between two codominant markers RPW and MRGH63B in linkage groupV. The genetic distances between Pm-AN and these two markers were 1.4–1.8 and 1.6–2 cM. No recombination was found between Pm-AN and markers ME/E1, SRAP23. Pm-AN was located in a RGA-rich region and cosegregated with the RGA marker MRGH5 and the resistance gene Vat. Synteny analysis showed that markers in this region were collinear between melon and cucumber. Segregation distortion was found in this region using both Ano2 × Hami413 and Ano2 × Queen F₂ populations, and the distortion was more distinct in Ano2 × Hami413 F₂ population. The center of segregation distortion was located in the RGA rich region harboring Pm-AN.