RAPD标记构建家蚕分子链锁图

以大造、Ｃ１０８及其Ｆ２群体构建了１个家蚕的ＲＡＰＤ连锁框架图,该图含ＲＡＰＤ标记位点１８２个,来自大造的１０３个标记分属前２３个连锁群,来自Ｃ１０８的７９个标记分属后１６个连锁群,覆盖基因组的总长度为１１４８．３ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ）,它能与本室用同一群体构建的ＳＡＤＦ图谱相整合,亦可与相应的ＲＦＬＰ图谱相互补充。     

RAPD标记构建家蚕分子连锁图

以大造、Ｃ１０８及其Ｆ２群体构建了１个家蚕的ＲＡＰＤ连锁框架图,该图含ＲＡＰＤ标记位点１８２个,来自大造的１０３个标记分属前２３个连锁群,来自Ｃ１０８的７９个标记分属后１６个连锁群,覆盖基因组的总长度为１１４８．３ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ）,它能与本室用同一群体构建的ＳＡＤＦ图谱相整合,亦可与相应的ＲＦＬＰ图谱相互补充。     

构建分子标记连锁图谱的图论构图方法

结合统计学、遗传学和图论原理,建立了一种新的分子标记连锁图谱构建的方法,即图论构图法．应用这种方法,从７７个家蚕ＲＡＰＤ标记位点中构建了７个标记位点的两个连锁群．与ＭＡＰＭＡＲＫＥＲ程序所构建的结果相比表明,图论构图法具有更为可靠的构图效果．     

利用RAPD标记构建响叶杨和银白杨分子标记连锁图谱

利用ＲＡＰＤ标记响叶杨（ Ｐｏｐｕｌｕｓ ａｄｅｎｏｐｏｄａ Ｍａｘｉｍ ．） ×银白杨（ Ｐ． ａｌｂａ Ｌ．） 的Ｆ１ 群体,按照拟测交的作图策略,分别构建了响叶杨和银白杨的分子标记连锁图谱。实验过程中对６００ 个随机的寡核苷酸引物进行了重复筛选,共选出１２８ 个引物用于作图群体的随机扩增,选择符合１∶１ 分离的拟测交位点。作图群体大小为８２ 个单株（ 包括双亲） 。结果获得了３２６ 个拟测交分离位点和７ 个３∶１ 分离位点。拟测交位点中有２３８ 个位点来源于银白杨,有８８个位点来源于响叶杨。经偏分离检测,用于银白杨作图的位点共计２１２ 个（２６ 个位点偏分离） ,用于响叶杨作图的位点共计７８ 个（１０ 个位点偏分离） 。利用多点连锁分析,银白杨中有１８９ 个连锁标记构成了２０ 个不同的连锁群（４个以上标记）,６ 个三连体和１６ 个连锁对,连锁标记覆盖的总图距为２４０２ ．４ ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ） 。而响叶杨有４１ 个连锁标记分属于１２ 个不同的连锁群（２ 个以上标记） ,标记覆盖的总图距为４７９ ．４ ｃＭ。获得了中等密度的银白杨连锁图谱和响叶杨图谱的一个连锁框架     

RAPD标记构建水稻分子连锁图

利用随机扩增多态性ＤＮＡ（ＲＡＰＤ）,在一个水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）的双单倍体（ＤＨ）群体中发展分子标记,仅用５２ 个ＲＡＰＤ标记建成了一个水稻ＲＡＰＤ分子连锁图。该图覆盖基因组的总长度为８９８．４ ｃＭ （ｃｅｎｔｉｍ ｏｒｇａｎ）,标记间的平均间距为１７．３ ｃＭ,它能与用同一群体构成的ＲＦＬＰ图谱互相补充     

中国白菜RAPD分子遗传图谱的构建

以芜菁（Ｂｒａｓｓｉｃａ ｃａｍｐｅｓｔｒｉｓ Ｌ．ｓｓｐ．ｒａｐｉｆｅｒａ Ｍｅｔｚｇ）和结球白菜（Ｂ．ｃａｒｎｐｅｓｔｒｉｓ Ｌ．ｓｓｐ ．Ｐｌｋｉｎｅｎｓｉｓ（Ｌｏｕｒ．）Ｏｉｓｓｏｎ）杂交的Ｆ２群体为试材,采用ＲＡＰＤ标记,用８４个１０核苷酸随机引物构建了白菜的ＲＡＰＤ遗传图谱。该图谱覆盖基因组的１６３２．４ｃＭ（ｃｅｒｔｉ Ｍｏｒｇａｎ）标记间的平均间隔为１６．５ｃＭ。其中最长的连锁群为     

利用分子标记定位农垦58S的光敏核不育基因

对农垦５８Ｓ（Ｏｒｙｚａｓａｔｉｖａｓｐ．ｊａｐｏｎｉｃａ）／大黑矮生标记基因系ＦＬ２组合组建可育集团和不育集团,并以亲本为对照进行了ＲＦＬＰ、ＲＡＰＤ和双引物ＲＡＰＤ分析,结果第１２染色体上的一个单拷贝标记Ｇ２１４０与光敏核不育基因连锁遗传,二者间的遗传图距为１４．１ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ）。在筛选过的１０４０个随机单引物和１９０个双引物中,仅引物ＯＰＡＵ１０扩增出与光敏核不育基因连锁的１．５ｋｂＤＮＡ片段,回收、克隆该ＤＮＡ片段并制备探针,将其转换成共显性的ＲＦＬＰ标记并命名为ＯＰＡＵ１０１５００。分离群体连锁分析表明该标记与标记Ｇ２１４０紧密连锁,将农垦５８Ｓ的一对光敏核不育基因定位于第１２染色体上。     

应用RAPD技术对不同基因组组合生物型遗传多态性的研究(英文)

利用ＲＡＰＤ技术对不同基因组合的鱼类进行了基因组指纹图谱构建,在ＤＮＡ水平上对基因组成分进行了分析,探讨了其遗传多态性。ＲＡＰＤ结果发现,在２６个随机引物扩增的产物中,平均每个个体观察到约１４２个ＲＡＰＤ标记,单个引物获得的标记平均为５．４。其中４个引物扩增的图谱可将不同的生物型区分开：Ｓ－２６引物的扩增图谱（Ｆｉｇ．１）可将红鲫（ＲＡ）与其它组合区分开,还可将鲤鲫杂种一倍体（ＣＡ）与鲫鲤杂种三倍体（ＣＡＡ）和人工复合三倍体鲤（ＣＣＡ）区分开;Ｓ－８引物（Ｆｉｇ．２）可区分开红鲤（ＲＣ）和镜鲤（ＭＣ）;Ｓ－４５引物（Ｆｉｇ．３）可区分开ＲＣ和ＣＡ;Ｓ－２２引物则可区分开ＣＡＡ和ＣＣＡ。六种生物型均存在基因组特异性的图谱即各自独特的“诊断性”图谱,作者由此建立了详细的分子标记检索表（Ｔａｂｌｅ１）。通过对ＲＡＰＤ图谱的量化分析,利用ＵＰＧＭＡ构建了不同生物型的遗传关系树图;反映了鲤鲫及各种组合生物型之间的遗传相似关系：ＲＣ和ＭＣ属同一种系,聚为一族;ＣＡＡ和ＣＡ基因组类型相同,聚为一族;ＣＣＡ虽自成一体,但可与ＣＡＡ和ＣＡ聚为一族;而ＲＡ与其它组合遗传距离较远,自成一族。ＲＡＰＤ的结果也表明各种生物型内个体间     

水稻DH群体的分子连锁图谱及基因组分析

利用扩大的籼粳杂交来源（窄叶青８号×京系１７）的水稻（ＯｒｙｚａｓａｔｉｖａＬ．）加倍单倍体（ＤＨ）群体,构建了包含４４４个位点的分子连锁图谱,覆盖水稻基因组１９６２ｃＭ（ｃｅｎｔｉＭｏｒｇｏｎ）,标记间的平均图距小于５ｃＭ。此图谱包括２７６个ＲＦＬＰ标记、３４个ＲＡＰＤ标记、８９个微卫星标记、１０个ＡＦＬＰ标记、２６个端粒重复相关序列（ＴＡＳ）标记以及９个同工酶标记。该遗传图谱与其它的水稻高密度遗传图谱具有较高的可比性,并有自己的特点,适于进行各种持续性的遗传学研究     

甘蓝型油菜分子标记连锁图谱的构建及显性细胞核雄性不育基因的图谱定位

在显性细胞核雄性不育系Rs1046A和双低油菜品种Samourai构建的回交分离群体中,运用AFLP和SSR两种标记技术构建了一个甘蓝型油菜(Brassica napus L.)的分子标记遗传连锁图谱。该图谱共包含138个AFL．P标记、83个SSR标记和1个形态标记,分布于18个主要连锁群、2个三联体和1个连锁对上,图谱总长度为2646cM,偏分离标记的比例为11．7％。显性细胞核雄性不育基因Ms被定位到第10连锁群(LG10)上。同时,偏分离标记聚集于第8连锁群(LG8)和第16连锁群(LGl6)的末端,形成了十分明显的偏分离标记密集区域。研究结果对于油菜核不育两型系的分子标记辅助选择育种具有重要意义,同时也为克隆和分离核不育基因以及研究核不育的分子机理打下了良好的基础。     

甘蓝分子连锁图的构建与品质性状的QTL定位

以两个不同生态型甘蓝(Brassica oleracea var．capitata)品种杂交得到的F2代为作图群体,用RAPD标记构建甘蓝分子连锁图。通过对520个随机引物进行筛选,236个引物在两亲本间表现多态性,多态性比例为47．7％。选取111个引物对群体进行分析,构建了一张含有135个标记位点,9个连锁群,覆盖长度为1023．7cM的分子连锁图。利用该图谱对甘蓝叶球紧实度和中心柱长两性状进行了QTL定位分析。检测到3个与叶球紧实度相关的QTL,总贡献率为62．5％;检测到4个与中心柱长相关的QTL,总贡献率为59．1％。     

Preliminary investigation of QTLs associated with seedling resistance to ascochyta blight from <Emphasis Type="Italic">Cicer echinospermum</Emphasis>, a wild relative of chickpea

Accessions from Cicer echinospermum, a wild relative of chickpea (Cicer arietinum L.), contain resistance to the fungal disease ascochyta blight, a devastating disease of chickpea. A linkage map was constructed based on an interspecific F(2) population, derived from a cross between a susceptible chickpea cultivar (Lasseter) and a resistant C. echinospermum accession (PI 527930). The linkage map incorporated 83 molecular markers, that included RAPD, ISSR, STMS and RGA markers; eight markers remained unlinked. The map comprised eight linkage groups and covered a map distance of 570 cM. Six out of the eight linkage groups were correlated to linkage groups from the integrated Cicer map using STMS markers. Quantitative trait loci (QTLs) associated with ascochyta blight resistance were detected using interval mapping and single-point analysis. The F(2) population was evaluated for seedling and stem resistance in glasshouse trials. At least two QTLs were identified for seedling resistance, both of which were located within linkage group 4. Five markers were associated with stem resistance, four of which were also associated with seedling resistance. QTLs from previous studies also mapped to LG 4, suggesting that this linkage group is an important region of the Cicer genome for resistance to ascochyta blight.     

Mapping of quantitative trait loci controlling broomrape (Orobanche crenata Forsk.) resistance in faba bean (Vicia faba L.).

Orobanche crenata Forsk. is a root parasite that produces devastating effects on many crop legumes and has become a limiting factor for faba bean production in the Mediterranean region. The efficacy of available control methods is minimal and breeding for broomrape resistance remains the most promising method of control. Resistance seems to be scarce and complex in nature, being a quantitative characteristic difficult to manage in breeding programmes. To identify and map the QTLs (quantitative trait loci) controlling the trait, 196 F2 plants derived from the cross between a susceptible and a resistant parent were analysed using isozymes, RAPD, seed protein genes, and microsatellites. F2-derived F3 lines were studied for broomrape resistance under field conditions. Of the 130 marker loci segregating in the F2 population, 121 could be mapped into 16 linkage groups. Simple interval mapping (SIM) and composite interval mapping (CIM) were performed using QTL Cartographer. Composite interval mapping using the maximum number of markers as cofactors was clearly the most efficient way to locate putative QTLs. Three QTLs for broomrape resistance were detected. One of the three QTLs explained more than 35% of the phenotypic variance, whereas the others accounted for 11.2 and 25.5%, respectively. This result suggests that broomrape resistance in faba bean can be considered a polygenic trait with major effects of a few single genes.     

Identification of QTLs associated with citrus resistance toPhytophthora gummosis

Citrus gummosis, caused by Phytophthora spp., is an important citrus disease in Brazil. Almost all citrus rootstock varieties are susceptible to it to some degree, whereas resistance is present in Poncirus trifoliata, a closely related species. The objective of this study was to detect QTLs linked to citrus Phytophthora gummosis resistance. Eighty individuals of the F1 progeny, obtained by controlled crosses between Sunki mandarin Citrus sunki (susceptible) and Poncirus trifoliata cv. Rubidoux (resistant), were evaluated. Resistance to Phytophthora parasitica was evaluated by inoculating stems of young plants with a disc of fungal mycelia and measuring lesion lengths a month later. Two QTLs linked to gummosis resistance were detected in linkage groups 1 and 5 of the P. trifoliata map, and one QTL in linkage group 2 of the C. sunki map. The phenotypic variation explained by individual QTLs was 14% for C. sunki and ranged from 16 to 24% for P. trifoliata. The low character heritability (h2 = 18.7%) and the detection of more than one QTL associated with citrus Phytophthora gummosis resistance showed that inheritance of the resistance is quantitative.     

Mapping of quantitative trait loci for partial resistance to<Emphasis Type="Italic"> Mycosphaerella pinodes</Emphasis> in pea (<Emphasis Type="Italic">Pisum sativum</Emphasis> L.), at the seedling and adult plant stages

The inheritance of resistance to Ascochyta blight, an economically important foliar disease of field pea (Pisum sativum L.) worldwide, was investigated. Breeding resistant pea varieties to this disease, caused by Mycosphaerella pinodes, is difficult due to the availability of only partial resistance. We mapped and characterized quantitative trait loci (QTLs) for resistance to M. pinodes in pea. A population of 135 recombinant inbred lines (RILs), derived from the cross between DP (partially resistant) and JI296 (susceptible), was genotyped with morphological, RAPD, SSR and STS markers. A genetic map was elaborated, comprising 206 markers distributed over eight linkage groups and covering 1,061 cM. The RILs were assessed under growth chamber and field conditions at the seedling and adult plant stages, respectively. Six QTLs were detected at the seedling stage, which together explained up to 74% of the variance. Ten QTLs were identified at the adult plant stage in the field, and together these explained 56.6–67.1% of the variance, depending on the resistance criteria and the organ considered. Four QTLs were detected under both growth chamber and field conditions, suggesting they were not plant-stage dependent. Three QTLs for flowering date and three QTLs for plant height were also identified in the RIL population, some of which co-located with QTLs for resistance. The relationship between QTLs for resistance to M. pinodes, plant height and flowering date is discussed.Communicated by H.C. Becker     

Integration genetic linkage map construction and several potential QTLs mapping of Chinese shrimp (Fenneropenaeus chinensis) based on three types of molecular markers

In this study, totally 54 selected polymorphic SSR loci of Chinese shrimp (Fenneropenaeus chinensis), in addition with the previous linkage map of AFLP and RAPD markers, were used in consolidated linkage maps that composed of SSR, AFLP and RAPD markers of female and male construction, respectively. The female linkage map contained 236 segregating markers, which were linked in 44 linkage groups, and the genome coverage was 63.98%. The male linkage map contained 255 segregating markers, which were linked in 50 linkage groups, covering 63.40% of F. chinensis genome. There were nine economically important traits and phenotype characters of F. chinensis were involved in QTL mapping using multiple-QTL mapping strategy. Five potential QTLs associated with standard length (q-standardl-01), with cephalothorax length (q-cephal-01), with cephaloghorax width (q-cephaw-01), with the first segment length (q-firsel-01) and with anti-WSSV (q-antiWSSV-01) were detected on female LG1 and male LG44 respectively with LOD> 2.5. The QTL q-firsel-01 was at 73.603 cM of female LG1. Q-antiWSSV-01 was at 0 cM of male LG44. The variance explained of these five QTLs was from 19.7-33.5% and additive value was from -15.9175 to 7.3675. The closest markers to these QTL were all SSR, which suggested SSR marker was superior to AFLP and RAPD in the QTL mapping.     

Molecular mapping of QTLs conferring stay-green in grain sorghum (Sorghum bicolor L. Moench).

Drought resistance is of enormous importance in crop production. The identification of genetic factors involved in plant response to drought stress provides a strong foundation for improving drought tolerance. Stay-green is a drought resistance trait in sorghum (Sorghum bicolor L. Moench) that gives plants resistance to premature senescence under severe soil moisture stress during the post-flowering stage. The objective of this study was to map quantitative trait loci (QTLs) that control the stay-green and chlorophyll content in sorghum. By using a restriction fragment length polymorphism (RFLP) map, developed from a recombinant inbred line (RIL) population, we identified four stay-green QTLs, located on three linkage groups. The QTLs (Stg1 and Stg2) are on linkage group A, with the other two, Stg3 and Stg4, on linkage groups D and J, respectively. Two stay-green QTLs, Stg1 and Stg2, explaining 13-20% and 20-30% of the phenotypic variability, respectively, were consistently identified in all trials at different locations in two years. Three QTLs for chlorophyll content (Chl1, Chl2, and Chl3), explaining 25-30% of the phenotypic variability were also identified under post-flowering drought stress. All coincided with the three stay-green QTL regions (Stg1, Stg2, and Stg3) accounting for 46% of the phenotypic variation. The Stg1 and Stg2 regions also contain the genes for key photosynthetic enzymes, heat shock proteins, and an abscisic acid (ABA) responsive gene. Such spatial arrangement shows that linkage group A is important for drought- and heat-stress tolerance and yield production in sorghum. High-resolution mapping and cloning of the consistent stay-green QTLs may help to develop drought-resistant hybrids and to understand the mechanism of drought-induced senescence in plants.     

Interval mapping of QTLs controlling yield-related traits and seed protein content in Pisum sativum

A linkage map of garden pea was constructed on the basis of 114 plants (F2 generation) derived from a cross combination Wt10245 x Wt11238. The map, consisting of 204 morphological, isozyme, AFLP, ISSR, STS, CAPS and RAPD markers, was used for interval mapping of quantitative trait loci (QTLs) controlling seed number, pod number, 1000-seed weight, 1000-yield, and seed protein content. Characterization of each QTL included identification of QTL position with reference to the flanking markers, estimation of the part of variance explained by this QTL, and determination of its gene action. The yield-related traits were measured in F2 plants and in F4 recombinant inbred lines (RILs). The interval mapping revealed two to six QTLs per trait, demonstrating linkage to seven pea chromosomes. A total of 37 detected QTLs accounted for 9.1-55.9% of the trait's phenotypic variation and showed different types of gene action. As many as eight and ten QTLs influencing the analysed traits were mapped in linkage groups III and V, respectively, indicating an important role of these regions of the pea genome in the control of yield and seed protein content.     

Identification of quantitative trait loci for bruchid (Caryedon serratus Olivier) resistance components in cultivated groundnut (Arachis hypogaea L.)

Groundnut bruchid (Caryedon serratus Olivier) is a major storage insect pest that significantly lowers the quality and market acceptance of the produce. Screening for resistance against groundnut bruchid in field conditions is difficult due to the variation in environmental factors and possible occurrence of biotypes. Hence, identification of tightly linked markers or quantitative trait loci (QTLs) is needed for selection and pyramiding of resistance genes for durable resistance. A population of recombinant inbred lines derived from a cross between VG 9514 (resistant) and TAG 24 (susceptible) was screened for five component traits of bruchid resistance in 2 years. The same population was genotyped with 221 polymorphic marker loci. A genetic linkage map covering 1,796.7 cM map distance was constructed with 190 marker loci in cultivated groundnut. QTL analysis detected thirteen main QTLs for four components of bruchid resistance in nine linkage groups and 31 epistatic QTLs for total developmental period (TDP). Screening in 2 years for bruchid resistance identified two common main QTLs. The common QTL for TDP, qTDP-b08, explained 57–82 % of phenotypic variation, while the other common QTL for adult emergence, qAE2010/11-a02, explained 13–21 % of phenotypic variation. Additionally, three QTLs for TDP, adult emergence and number of holes and one QTL for pod weight loss were identified which explained 14–39 % of phenotypic variation. This is the first report on identification of multiple main and epistatic loci for bruchid resistance in groundnut.     

Development of an AFLP-based linkage map and localization of QTLs for seed fatty acid content in condiment mustard (Brassica juncea).

A genetic linkage map of Brassica juncea based on AFLP and RAPD markers was constructed using 131 F1-derived doubled-haploid (DH) plants from a cross between two mustard lines. The map included 273 markers (264 AFLP, 9 RAPD) arranged on 18 linkage groups, and covered a total genetic distance of 1641 cM; 18.3% of the AFLP markers showed a segregation distortion (P < 0.01). The markers with biased segregation were clustered on seven linkage groups. QTLs for oil contents, palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), linolenic acid (18:3), eicosenoic acid (20:1), and erucic acid (22:1), were mapped on the AFLP linkage map. Correlation studies among fatty acids in the DH population and the localization of QTLs involved in their control indicated that a major gene located on linkage group (LG) 2 controlled the elongation step of erucic acid.