Incidence and molecular markers of 2n pollen in Populus tomentosa Carr

Incidence and molecular markers of 2n pollen in Populus tomentosa Carr     

适于家蚕AFLP标记的酶切反应系统

ＡＦＬＰ作为一种新的分子标记技术，其成功的关键依赖于ＤＮＡ的酶解效果，本文使用ＰｓｔＩ、ＴａｑＩ两种限制性内切酶，选用不同的酶切方式与不同的反应离子的组合对家蚕ＢＣ１代基因组ＤＮＡ进行酶切、通过人工接头连接、二次扩增及ＰＡＧＥ电泳、银染检测，结果显示是两酶在２５ｍＭＴｒｉｓ－Ａｃｅｔａｔｅ（ＰＨ７．８）、１００ｍＭＫＡｃ、１０ｍＭＭＧＡｃ２、１ｍＭＤＴＴ反应系统中能得到多态性丰富、重复性好的ＤＮＡ指纹图谱。同时，表明寻求适宜的限制酶缓冲组分是十分重要的。     

AFLP分子标记技术及其在林木遗传育种上的应用

ＡＦＬＰ是以ＰＣＲ扩增为基础的，是扩增片段长度多态性的简称。它是ＲＦＬＰ和ＰＣＲ相结合的一种标记技术，其基本原理是对组ＤＮＡ限制性酶切片断的选择性扩增。ＡＦＬＰ的基本反应过程包括模板ＤＮＡ制备、酶切片段的扩增和扩增产物的凝胶电泳分析３个步聚。ＡＦＬＰ是一种新颖和强大的ＤＮＡ指纹技术，结合了ＲＦＬＰ和ＲＡＰＤ的优点，具有高效、快捷、稳定、可靠的特点。本文将ＡＦＬＰ和ＲＦＬＰ、ＲＡＰＤ、ＳＳＲ等分子标     

适于AFLP分析用的桃成熟叶片DNA提取方法

以多个野生桃秋季成熟叶片为材料,采用改进CTAB法对其基因组总DNA的提取进行了研究,并与其相应幼叶DNA的提取效果进行了比较分析。结果表明,从野生桃成熟叶片提取的DNA除产量低于幼叶外,DNA的纯度和完整性都较好,D260nm/D280nm的比值均为1.8～2.0,无降解现象,RNA去除干净,能被限制性内切酶完全消化;其AFLP分析(引物EcoRI-TA/MseI-CTT)条带清晰,多态性好,说明此方法提取的野生桃成熟叶片基因组总DNA完全适于AFLP分析。     

Population structure,races, and host range of <Emphasis Type="Italic">Aphanomyces euteiches</Emphasis> from alfalfa production fields in the central USA

Aphanomyces euteiches (races 1 and 2) causes root rot of alfalfa; however, its population biology and distribution are poorly understood where alfalfa is a major crop. The objectives of this study were to (1) characterise the distribution and frequency of races of A. euteiches in Illinois alfalfa fields, (2) determine host range of A. euteiches on cultivated and native legumes, and (iii) to describe genetic diversity and population genetic structure of A. euteiches in alfalfa fields. To accomplish this, soil samples (n = 103) were collected from 30 alfalfa fields in 18 Illinois counties. Using the susceptible cv. ‘Saranac’, 148 isolates of A. euteiches were baited from the soil. The virulence phenotype of isolates representing all 18 counties was tested, and 54% were R1 and 46% were R2. Both races were detected in 61% of the counties, whereas only R1 was detected in 22% and R2 in 17%. Thirteen legume hosts for isolates from alfalfa fields were identified based on symptoms and/or production of oospores in roots. In addition to six previously known hosts, seven species were susceptible to infection: kura clover, purple prairie clover, white prairie clover, ladino clover, hairy vetch, Canadian milk vetch, and Illinois tick trefoil. AFLP analysis revealed high levels of genetic diversity among the isolates from different fields and counties and a lack of genetic structuring of populations based on race or geographical origin. The results suggest that populations of A. euteiches in alfalfa fields are diverse, often composed of races 1 and 2, and create risk for alfalfa and to multiple cultivated and native legume species.     

利用AFLP技术对谷子光敏雄性不育基因进行分子标记

利用AFLP技术对谷子光敏雄性不育基因进行了分子标记,对96对引物进行了筛选,通过Kosambi函数计算,P56/M40和P56/M76的引物组合与基因间的连锁距离为10.14,15.46 cM。     

春石斛杂交育种及亲缘关系的AFLP分析

春石斛Dendrobium nobile为亚热带花卉。为了解决种苗依赖进口的问题,从2002年开始,从国内外引进春石斛资源,从中精选符合中国国情的花色品种和单株作为杂交育种材料,从2002-2006年授粉组合共计345个,成功育苗144个,成功率41.74%,所得杂交后代5029号和5041号2个最符合育种目标。对30个引进的品种和杂交获得的品种进行荧光AFLP（扩增片断长度多态性）分析,构建春石斛新品种的DNA指纹图谱,为品种鉴定、评价和品种创新、新品种保护提供可靠方便的技术手段。     

Characterization of avian strains of Pasteurella multocida by restriction endonuclease and amplified fragment length polymorphism

Avian strains of Pasteurella multocida were typed by employing restriction endonuclease analysis (REA) and single enzyme-amplified fragment length polymorphism (AFLP) to evaluate their applicability for epidemiological studies of fowl cholera outbreaks. A total of 72 strains isolated from different avian species (chicken, duck, turkey, quail and goose) belonging to various geographical regions of India were characterized. REA using two different enzymes HhaI and HpaII produced 9 and 18 clusters respectively, whereas Single enzyme-AFLP recognized 32 patterns out of 72 strains typed. The study indicated that REA using HpaII is a simple and resource efficient method, however, further typing with more stringent and rapid method like Single enzyme-AFLP, could drastically enhance investigation in epidemiological studies of fowl cholera outbreaks.     

奶山羊间性个体的遗传鉴定及AFLP指纹图谱分析

【目的】分析奶山羊间性个体的遗传背景,探讨间性个体发生的遗传机制,为山羊性别调控以及性别决定的研究提供参考。【方法】通过核型分析、特异性性别调控基因(Sex-determining region of Y chromosome,SRY)的PCR扩增以及AFLP(Amplified fragment length polymorphism)指纹图谱分析等方法,研究西农萨能羊间性个体的遗传本质。【结果】间性山羊与正常母山羊的核型一致,为58+XX;间性个体基因组中未能扩增出SRY基因;AFLP指纹图谱分析发现,有9对引物扩增出清晰的条带,共1 833条,片段长度为70～500bp,9对引物的扩增结果差异明显,表现出丰富的多态性,共获得611个多态位点,占总扩增条带数的33.3%,但在基因组水平上间性山羊与正常母山羊个体并没有大的差异。【结论】根据试验结果推测,间性山羊的出现并非是由个体基因组发生突变造成的,可能是在性别决定过程中某个因子的调控出现差错,从而导致胚胎在发育过程中偏离雌性轨道而产生间性山羊个体,其具体机制有待进一步研究。     

异子蓬异型种子萌发基因差显的cDNA AFLP技术体系优化

以异子蓬种子为材料,建立并优化其萌发过程中基因表达差显的cDNA-AFLP技术体系。分别以总RNA和mRNA反转录的双链cDNA为模板,对25μL PCR扩增体系中的退火温度、引物量、DNA聚合酶种类及电泳条件进行优化。结果显示,以分离的mRNA为模板可以反转录得到品质较好的双链cDNA;PCR扩增选择较高退火温度(第1轮为56℃,第2轮为65～56℃)、引物量为1μL(10μmol/L)、使用高效PremixLA Taq Hot Start DNA聚合酶、在约800V电压下进行60g/L变性聚丙烯酰胺凝胶电泳,可得到条带清晰、多态性好的cDNA-AFLP结果。