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1.
为探究绵羊Cry1基因g.175355119T>C、g.175357583C>T位点与Cry2基因g.74126865C>T位点多态性与绵羊产羔数之间的关系,本实验利用全基因组重测序结合Sequenom MassARRAY?SNP技术对常年发情绵羊品种(小尾寒羊、湖羊和策勒黑羊)和季节性发情绵羊品种(滩羊、苏尼特羊和草原型藏羊)Cry1基因与Cry2基因共3个多态位点多态性进行检测,并与小尾寒羊产羔数进行关联分析。结果表明:Cry1基因g.175355119T>C位点存在CC、CT和TT 3种基因型,g.175357583C>T位点存在TT、TC和CC 3种基因型;Cry2基因g.74126865C>T位点存在CC、CT和TT 3种基因型。群体遗传学分析表明,Cry1基因g.175355119T>C位点与Cry2基因g.74126865C>T位点的基因型频率和等位基因频率在2种发情模式绵羊品种间的差异均达到极显著水平。在6个绵羊品种中,Cry1基因g.175355119T>C位点与g.175357583C>T位点均表现为中度多态(0.25T位点均表现为低度多态(PIC<0.25)。卡方适合性检验表明,Cry1基因g.175355119T>C位点在6个绵羊品种中均处于哈代温伯格平衡状态(P>0.05),g.175357583C>T位点在苏尼特羊中处于哈代温伯格不平衡状态(P<0.05),Cry2基因g.74126865C>T位点在滩羊和草原型藏羊中处于哈代温伯格不平衡状态(P<0.05)。关联分析表明,3个多态位点与小尾寒羊第1、第2以及第3胎产羔数均无显著关联(P>0.05)。综上,Cry1基因g.175355119T>C、g.175357583C>T位点与Cry2基因g.74126865C>T位点均不适用于小尾寒羊产羔数选育。  相似文献   
2.
试验旨在探究SPP1基因g.36651870T>C位点多态性、PLCB3基因g.41871219T>C位点多态性与绵羊产羔数之间的关系,以期寻找绵羊产羔数性状相关的分子标记。利用全基因组重测序结合Sequenom MassARRAY誖SNP技术对多羔羊(小尾寒羊、湖羊、策勒黑羊)和单羔羊(滩羊、苏尼特羊、萨福克羊和草原型藏羊)7个绵羊品种SPP1、PLCB3基因的2个位点进行多态性检测,并与小尾寒羊产羔数进行关联分析。结果表明:2个位点均存在TT、TC和CC三种基因型。SPP1基因g.36651870T>C位点的基因型频率和等位基因频率在两类绵羊品种间差异极显著(P<0.01);PLCB3基因g.41871219T>C位点基因型频率在两类绵羊品种间差异不显著(P>0.05),等位基因频率差异显著(P<0.05)。群体遗传学分析表明,SPP1基因g.36651870T>C位点在小尾寒羊、苏尼特羊、萨福克羊和湖羊中均表现为中度多态(0.25≤PIC<0.5),在滩羊、策勒黑羊和草原型藏羊中表现为低度多态(PIC<0.25);PLCB3基因g.41871219T>C位点在滩羊中表现为中度多态(0.25≤PIC<0.5),在其余6个绵羊品种中均表现为低度多态(PIC<0.25)。卡方适合性检验表明,SPP1基因g.36651870T>C位点在7个绵羊品种中均处于哈代-温伯格平衡状态(P>0.05);PLCB3基因g.41871219T>C位点在小尾寒羊、滩羊、苏尼特羊、策勒黑羊、草原型藏羊5个品种中处于哈代-温伯格平衡状态(P>0.05)。关联分析表明,PLCB3基因g.41871219T>C位点多态性与小尾寒羊第1胎产羔数有显著关联(P<0.05),TT基因型个体产羔数显著高于CC基因型个体;SPP1基因g.36651870T>C位点多态性与小尾寒羊不同胎次产羔数之间无显著关联(P>0.05)。综上,PLCB3基因g.41871219T>C位点对小尾寒羊产羔数性状选育具有一定的参考意义,SPP1基因g.36651870T>C位点不适用于小尾寒羊产羔数性状选育。  相似文献   
3.
We developed 178 recombinant inbred lines from a southern‐by‐spring oat population designated as “TxH.” These lines were genotyped to generate a high‐quality linkage map that resolved 6,902 markers into 21 linkage groups that matched closely with the latest hexaploid oat consensus map. Three major quantitative trait loci (QTLs) affecting heading date were found in locations that are consistent with known QTLs and candidate genes, and two other QTLs affecting heading date were found in novel locations. Five QTLs affecting plant height were found. Both sets of QTLs are responsible for transgressive segregation observed for these two traits. Four QTLs affecting resistance to crown rust, caused by the pathogen Puccinia coronata f. sp. avenae, were identified. Two of these QTLs are consistent with known clusters of rust resistance genes, while two may represent new locations of novel rust resistance genes. A complete set of SNP sequences suitable for generating markers for molecular selection is provided.  相似文献   
4.
5.
Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey.  相似文献   
6.
Soybean is the most important oilseed and protein crop worldwide, but in Europe, the acreage is comparably low. Thus, Europe strongly depends on imports of soy products and consequently recent efforts aim at expanding the acreage of soybean, particularly in Central Europe. The aim of this study was, therefore, to assist these breeding efforts by characterizing Central European soybean germplasm, employing a genotyping‐by‐sequencing approach yielding 7741 genomewide distributed markers. Our analysis on genetic diversity and population structure revealed that the Central European lines are most closely related to Swiss and Canadian lines and somewhat more distant from the investigated Chinese and US lines. In addition, we analysed patterns of allelic diversity and the extent of linkage disequilibrium. Collectively, our results can assist breeding of Central European soybean and suggest that further progress can be made by crosses among adapted material but a long‐term success also requires introgression of alleles from non‐European germplasm to further broaden the genetic diversity and incorporate novel traits.  相似文献   
7.
A collection of 96 Polish isolates of Phytophthora infestans sampled in the years 2006, 2008 and 2009 were analysed using phenotypic and genotypic markers. Mating type, virulence, resistance to metalaxyl, mitochondrial haplotype and polymorphism at 12 simple sequence repeat (SSR) loci were determined. The majority of isolates were of the A1 mating type, mitochondrial haplotype Ia and sensitive to metalaxyl. Virulence factors against potato R genes R1, R3, R4, R7, R10 and R11 were present in most isolates. Genotyping using SSR markers revealed high genetic diversity within the Polish P. infestans population. Amongst the 96 isolates 66 unique genotypes were identified, 49 of which were observed only in single isolates. Eight isolates of the genotype 13_A2 lineage that has been reported in other parts of Europe were also found in Poland. The implications of these results are discussed.  相似文献   
8.
Insight into pathogen population dynamics provides a key input for effective disease management of the potato late blight pathogen Phytophthora infestans. Phytophthora infestans populations vary from genetically complex to more simple with a few clonal lineages. The presence or absence of certain strains of P. infestans may impact the efficacy of fungicides or host resistance. Current evidence indicates that genetically, the Irish populations of P. infestans are relatively simple with a few clonal lineages. In this study, P. infestans populations were genetically characterized based on samples collected at the national centre for potato breeding during the period 2012–16. The dominance of clonal lineages within this P. infestans population was confirmed and the potential selection pressure of fungicide treatment (2013–15) and host resistance (2016) on this clonal P. infestans population was then investigated. It was found that fungicide products did not notably affect the genetic structure of sampled populations relative to samples from untreated control plants. In contrast, samples taken from several resistant potato genotypes were found to be more often of the EU_13_A2 lineage than those taken from control King Edward plants or potato genotypes with low resistance ratings. Resistant potato varieties Sarpo Mira and Bionica, containing characterized R genes, were found to strongly select for EU_13_A2 strains.  相似文献   
9.
Erythrocyte pyruvate kinase (PK) deficiency is an inherited glycolytic erythroenzymopathy caused by mutations of the PKLR gene. A causative mutation of the feline PKLR gene was originally identified in Abyssinian and Somali cats in the U.S.A. In the present study, a TaqMan probe-based real-time PCR genotyping assay was developed and evaluated for rapid genotyping and large-scale screening for this mutation. Furthermore, a genotyping survey was carried out in a population of four popular purebred cats in Japan to determine the current mutant allele frequency. The assay clearly displayed all genotypes of feline PK deficiency, indicating its suitability for large-scale survey as well as diagnosis. The survey demonstrated that the mutant allele frequency in Abyssinian and Somali cats was high enough to warrant measures to control and prevent the disease. The mutant allele frequency was relatively low in Bengal and American Shorthair cats; however, the testing should still be carried out to prevent the spread of the disease. In addition, PK deficiency should always be considered in the differential diagnosis of anemia in purebred cats in Japan as well as worldwide.  相似文献   
10.
[目的]探讨采用基因分型方法对非典型布鲁菌鉴定的实用性,为非典型菌株的鉴别提供参考。[方法]采用常规鉴定方法和VITEK 2.0全自动细菌鉴定分析系统对菌株进行初步鉴定,利用AMOS-PCR进行种型鉴定,应用多位点可变数目串联重复序列分析方法(MLVA)确定菌株的基因型。[结果]常规鉴定结果显示试验菌株为疑似布鲁菌;VITEK 2.0全自动细菌鉴定系统显示3株试验菌株均为布鲁菌;AMOS-PCR扩增表明试验菌株均为羊种菌,MLVA聚类分析表明试验菌株与羊种2型布鲁菌紧密地聚为一类,属东地中海基因型,并在Panel 2B中发现了新的基因型(4-4-3-7-5),命名为CN2B-45。[结论]MLVA基因分型方法对非典型布鲁菌具有极高的分辨力,是非典型布鲁菌分型鉴别的最佳策略。  相似文献   
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