AFLP,SSR在黄瓜黑星病抗感材料上的多态性比较

用AFLP和SSR 2种分子标记技术对黄瓜抗感黑星病材料Q6和Q12,及其F2极性集团和F2群体进行了分析,比较了它们的多态性。结果表明,AFLP和SSR 2种分子标记的多态性比率分别为36.5%,9.6%;阳性比率分别为22%,0。在F2群体中找到了1个AFLP标记E20/M64,与目的基因的遗传距离是4.83 cM;1个SSR标记CSWCT02B,与目的基因的遗传距离是28.7 cM。AFLP的多态性比率要比SSR的多态性比率高。分析探讨了2种分子标记技术的优缺点及其在目的基因连锁标记筛选、基因定位等研究中的应用。     

小麦合成种M53抗白粉病基因的RAPD和SSR标记

运用RAPD和SSR技术，采用分离群体分组分析法(BSA)进行了小麦合成种M53抗白粉病基因连锁的分子标记研究。结果表明，M53的抗白粉病基因由显性单基因控制，RAPD标记OPL09-1700与抗病基因连锁，遗传距离为16.8cM。SSR标记Xgwm205也与抗白粉病基因连锁，遗传距离为9.3cM，通过SSR标记将该基因定位于5DS，标记与基因间的排列顺序     

陆地棉亚红株突变体基因的初步定位

陆地棉亚红株突变体PD-17与GK19杂交F₁代表现出良好的光合作用效率,具有较高的超亲优势,是潜在的优良种质资源。寻找与该突变基因Rs连锁的分子标记并进行染色体定位,对于该基因的进一步精细定位或克隆具有重要的意义。以亚红株突变体PD-17与GK19配置的BC1群体为作图群体,选用覆盖棉花所有已鉴定染色体及大多数连锁群的419对SSR引物,利用BSA（bulked segregation analysis）法筛选有多态性差异引物,然后根据群体单株基因型进行作图分析。结果显示,位于第7条染色体上的5个分子标记与Rs基因相连锁,SSR标记BNL2634与Rs基因的遗传距离较小,约为10.3 cM,SSR标记CIR393位于Rs基因另一侧,与Rs基因的遗传距离约为29.1 cM,由此,可将Rs基因定位于第7染色体上。     

陆地棉高秆突变体的激素变化与Tp基因的染色体定位

以高秆突变体高秆1号为试验材料,常规品种N099为对照,利用酶联免疫法测定突变体种子浸泡24 h后种胚中激素含量。结果表明,高秆1号的3种激素GA3、ZR、IAA的含量均高于对照,其中GA3的含量显著高于对照。杂交F1表现为:GA3含量显著高于两亲本,但ZR、IAA含量比正常株高亲本还要低。这暗示高秆1号是一种GA3富集型突变体;而与ZR、IAA关联不大。采用陆陆杂交群体对高秆基因进行染色体定位,有4个SSR分子标记与Tp基因连锁,分别是NAU2083、NAU4045、NAU2419和NAU4044,位于Tp基因两侧的分子标记为NAU4045和NAU2419,其遗传距离分别为7.4 c M和41.2 c M。由此,将陆地棉的一个高秆突变体基因Tp定位在棉花Chr.1上。     

小麦抗麦红吸浆虫的抗性研究利用及展望

该文综合阐述了二十世纪80年代以来,国内外关于麦红吸浆虫抗虫鉴定筛选、抗虫机制、抗性基因遗传以及抗虫基因定位、分子标记等方面的研究进展及展望。并结合笔者研究结果采用SSR分子标记在7B染色体上找到了与冀麦24小麦品种抗麦红吸浆虫抗性基因连锁的标记Wms400,遗传距离为5cM。以期为小麦抗虫育种的应用提供参考,为抗虫基因的克隆和基因转化技术研究打下基础,并促进小麦生产的持续发展     

利用海岛棉染色体片段导入系定位衣分和籽指QTL

以染色体片段导入系IL-15-5和IL-15-5-1构建的F2和F2:3分离群体,利用SSR标记对数量性状衣分和籽指QTL进行了定位。应用复合区间作图法分析两个组合的774个F2单株和F2:3家系衣分和籽指,检测到2个衣分的QTL,1个籽指的QTL。衣分QTLqLP-15-1在两世代中都被检测到,位于相同的分子标记置信区间JESPR152～NAU3040,置信的遗传距离分别为5.40cM和3.20cM;qLP-15-2只在F2:3中被检测到,位于分子标记NAU5302～NAU2901之间,置信的遗传距离为0.08cM。籽指QTLqSI-15-1在F2和F2:3中都被检测到,分别位于分子标记NAU2814～NAU3040和JESPR152～NAU3040,置信的遗传距离分别为6.70cM和5.70cM。利用染色体片段导入系能准确地定位产量组分的QTL,为棉花产量的分子设计育种奠定基础。     

小麦花粉致死基因Ki的SSR标记分析

小麦雄性不育主要是通过花粉的败育表现,其不育材料对小麦杂种优势的利用研究具有重要意义和价值,国外研究表明,某些特定普通小麦品种间杂交F₁表现的花粉部分不育现象,受控于核基因组花粉致死基因Ki,为了筛选小麦花粉致死基因Ki的连锁标记,利用现代分子生物学技术通过定位该基因,克隆出花粉致死基因连锁标记片段,为小麦雄性不育种质材料的转育提供有效的选择标记。对小麦花粉致死基因Ki进行了分子标记定位,以‘中国春’和澳大利亚春小麦品种的BC₁F₁代作为定位群体,利用分离群体分组分析法(BSA)对位于小麦6B染色体上85对SSR引物进行多态性筛选,具有多态性的引物再通过BC₁F₁定位群体进行验证,从中筛选出与目的基因连锁的2个SSR标记Xgwm626和Xgpw4138。运用Mapmaker 3.0软件进行连锁分析。结果表明,Xgwm626和Xgpw4138与Ki基因的遗传距离分别为9.2 cM和6.9 cM,且2个SSR标记位于目的基因两侧,并将Ki定位于小麦6BL染色体上。研究结果为Ki基因的分子标记辅助选择和进一步精细定位奠定了基础。     

陆地棉5个突变基因的标记与定位

本文以3个陆地棉突变体材料T582、T586、ml分别与海7124杂交获得的F2作为标记群体，对红株（R1）、花粉颜色（P1）、芽黄（v1）、花瓣叶（ml）、丛生铃（cl1）这5个表型性状进行基因定位，用Mapmaker／Exp3．0b进行连锁分析，将红茎基因（R1）定位于第16条染色体的NAU751和NAU450标记之间，与它们的遗传距离分别是5．3cM，11．3cM；黄花粉基因（P1）定位在第5条染色体的NAU569c和CIR253b之间，与它们的遗传距离分别是5．2cM，5．5cM；芽黄基因（v1）定位在第20条染色体上，与CIR094a的遗传距离为10．3cM；花瓣叶基因（ml）定位在第4条染色体上，与SSR标记位点NAU2623a的距离为0．6cM；丛生铃基因（cl1）定位在第16条染色体上，与BNL1694a的遗传距离为0．1cM，并且cl1和R1，的遗传距离为45．9cM。     

一个抗赤星病基因的SSR标记连锁群

为筛选到与抗赤星病基因连锁更加紧密的SSR标记,并绘制出抗病基因的SSR标记连锁图。本研究以一个位于M号连锁群上且与净叶黄抗赤星病基因有连锁关系的SSR标记为基础,将高密度遗传连锁图谱中位于M号连锁群上的130对SSR引物进行合成及扩增筛选,通过数据分析,获得了一个抗赤星病基因的SSR标记连锁群。该连锁群包括12个标记,全长181.5cM,平均间距15.1cM,抗性基因被定位在标记J4与J9之间,其中与J9的遗传距离仅为4cM,为下一步抗性基因的精细定位奠定了良好的基础。     

转基因抗虫棉Bt基因的遗传连锁分析

对中美两国所获得的转基因抗虫棉品种GK— 1 2、新棉 33B分别进行了 Bt基因的连锁测验。分析表明两个品种的试验结果相似 ,Bt基因未整合在棉花第 I、II、III、IV、V、VI、VII、IX、X、XI、XII、XIII、XVII连锁群及 cu、pg、gl1等基因所涉及的染色体上。阐明了 Bt基因染色体图谱定位的复杂性 ,并提出以原位杂交技术实现 Bt基因在棉花染色体组上的物理标图     

Analysis of Genetic Polymorphic SSR Markers in Germplasm Resources of the Natural Colored Cotton

Short sequence repeats (microsatellite,SSR) and expressed sequence tags-SSR (EST-SSR) markers were employed to analyze the genetic diversity of natural colored cotton varieties.About 490 pairs of SSR markers spanning the 26 chromosomes were selected from the cotton microsatellite database,they were composed of the NAU,BNL,MUSS,and CIR markers,and there was one marker every 5 cM on average.     

2005-2020年转Bt基因棉花抗虫性变化及其与产量性状的相关性分析

为了给转Bt基因棉花在科研和生产上多世代可持续利用提供依据，以转Bt基因棉花品种银山8号为试验材料，从2005年开始，连续16年进行跟踪研究。结果表明，随种植世代的增加，生物测定银山8号第2～4代棉铃虫幼虫校正死亡率、铃期叶片和铃期小铃杀虫蛋白表达量均有不同程度的线性上升趋势，同时皮棉产量线性回归也呈增长趋势；苗期叶片、蕾期叶片和蕾期小蕾杀虫蛋白表达量呈线性下降趋势。相关性分析表明，抗虫棉的抗虫性与皮棉产量间均呈正相关，株铃数和衣分是构成皮棉产量的重要因子，与皮棉产量的相关性分别达到极显著和显著水平。外源Bt基因转入棉花后能稳定遗传给后代，通过卡那霉素鉴定和系统选择可以持续保持转Bt基因棉花多世代的抗虫性，甚至通过提纯复壮逐年优选，可实现转Bt基因抗虫棉特定生育时期或部分棉花器官抗虫性的提高。     

利用染色体片段代换系定位棉花抗黄萎病QTL

通过陆地棉与海岛棉杂交并与陆地棉回交,获得1个染色体片段代换系苏VR043,抗江苏非落叶型黄萎病菌系BP2。分子检测表明,苏VR043兼有陆地棉苏棉8号的遗传背景和海7124的D4染色体片段。以苏VR043和苏棉8号为亲本构建包含176个单株的F2群体,通过标记分析和F2:3家系抗病鉴定,发现抗病性状与标记NAU3392连锁,p值为2.3×10-12。根据棉花D组染色体测序结果,参照置换区段的基因组序列,合成92对SSR引物;PCR扩增分析发现,有5对引物在苏棉8号和苏VR043之间表现多态性,并将抗病主效QTL定位在标记ZHX32和NAU3392之间,标记间遗传距离为3.2 c M,QTL解释表型变异64.8%。同时参照棉花D组测序结果,提取对应的置换区段序列,预测包含63个基因,基因聚类分析表明7个基因参与抗逆反应,其中1个基因与抗病相关。     

Molecular mapping of genic male-sterile genes ms15, ms5 and ms6 in tetraploid cotton

Two genic male sterile (GMS) lines, Lang-A conditioned by ms ₁₅ and Zhongkang-A conditioned by ms ₅ ms ₆ duplicate recessive genes in Gossypium hirsutum L., were chosen to map GMS genes. These two lines were crossed with Gossypium barbadense cv. 'Hai7124' to produce segregating populations. The ms ₁₅ gene was mapped on chromosome 12, and was flanked by two simple sequence repeat (SSR) markers, NAU2176 and NAU1278, with a genetic distance of 0.8 and 1.9 cM respectively. The ms ₅ and ms ₆ genes were mapped to one pair of homoeologous chromosomes, ms ₅ on chromosome 12 flanked by three SSR markers, NAU3561, NAU2176 and NAU2096, with genetic distances of 1.4, 1.8 and 1.8 cM, respectively, and ms ₆ on chromosome 26 flanked by two SSR markers, BNL1227 and NAU460, with a genetic distance of 1.4 and 1.7 cM respectively. These tightly linked markers with the ms ₁₅ , ms ₅ and ms ₆ genes can be used in the marker-assisted selection among segregating populations in a breeding programme, and provide the foundation for gene isolation by map-based cloning for these three genes.     

Fine mapping of the uniform immature fruit color gene u in cucumber (Cucumis sativus L.)

Mottled/uniform color at the flower end of immature fruit is a highly important external quality trait that affects the market value of cucumber. Genetic analysis of different F₂ and backcross populations revealed that one single recessive gene, u (uniform immature fruit color), determines the uniform immature fruit color trait in cucumber. Based on earlier studies, the u locus is located on chromosome 5 (Chr. 5). By combining bulked segregant analysis using 60 published molecular markers on Chr. 5, we found that eight markers are polymorphic and are linked to the u locus. In addition, we developed five new relevant polymorphic simple sequence repeat (SSR) markers between markers SSR16203 and SSR15818. Subsequently, the F₂ population (477 individuals) from the cross of S06 (uniform fruit color line) × S94 (mottled fruit color line) was used for fine mapping of the u gene. The u gene was mapped to a 313.2-kb region between markers SSR10 and SSR27, at a genetic distance of 0.8 and 0.5 cM, respectively. Moreover, validity analysis of the codominant markers SSR10 and SSR27 was performed using 50 lines with mottled/uniform fruit color, demonstrating that these two SSR markers can be used for marker-assisted selection of the mottled/uniform fruit color trait in cucumber breeding. The results of this study will facilitate the cloning of the u gene.     

Effects of Leaf Position of Transgenic Cotton on the Population Growth of Spodoptera exigua in the Early Growth Stage

[Objective] Cotton has recently become one of the main hosts of Spodoptera exigua (Hübner), a moth species that damages the leaves of plants. With the widespread application and popularization of transgenic insect-resistant cotton, it is essential to understand the significance of leaf position on the population growth of S. exigua to effectively manage this pest. Leaf position was determined by the preference of this pest for the upper and middle leaves of cotton. [Method] To study the effects of different leaf positions on S. exigua population growth, we used three different kinds of transgenic cotton (transgenic cry1A cotton GK12, transgenic cry1Ac cotton Nu COTN 33B, and transgenic cry1A+CpTI cotton SGK321). We tested these three transgenic cotton varieties alongside their corresponding parental non-Bt transgenic cotton varieties (Simian 3, DP5415, and Shiyuan 321) as controls, respectively. We describe our results in the form of a population life table. [Result] (1) GK12 and SGK321 had an inhibitory effect on S. exigua, which exhibited some differences with the change of feeding position. The population trend index was substantially larger than 1. (2) Although there was an influence on the growth and reproduction of S. exigua after feeding on different leaf positions of the same transgenic cotton, the results show no apparent trend of change among leaf positions. (3) The population index of S. exigua that fed on Nu COTN 33B and SGK321 showed a lower tendency than that on conventional cotton varieties, but there was no significant difference between the population index for the S. exigua that fed on GK12 and Simian 3. [Conclusion] The population growth of the S. exigua that fed at different leaf positions on the three varieties of transgenic cotton increased throughout the experiment. This continuous population growth indicates that the transgenic cotton crops require additional management actions to control of the pest species, S. exigua.     

基于简化基因组的甜叶菊分子标记开发

本研究旨在筛选和开发具有多态性的甜叶菊基因组分子标记。选取4个甜叶菊品种为材料,利用简化基因组测序技术(RAD-seq)开发SSR和SNP标记。开发并验证了149对多态性丰富、重复性好、特异性高的简单重复序列(SSR)和4组功能性的SNP标记,开发的多态性基因组分子标记中包含了甜叶菊糖苷合成途径关键基因的新标记StKASPSNP-7。验证了基于KASP技术开发甜叶菊功能SNP标记的可行性,为甜叶菊遗传图谱构建、分子鉴定奠定了基础。本研究开发的SSR和SNP标记可应用于甜叶菊的遗传图谱分析、品种真实性的高效快速鉴定以及高糖苷含量新品种的开发。