排序方式: 共有74条查询结果,搜索用时 15 毫秒
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核桃BES-SSR的开发及在遗传多样性分析中的应用 总被引:3,自引:2,他引:1
从NCBI 数据库全部已知核桃MboI 基因组BAC 文库克隆中下载22 740 条末端序列(BAC end sequences,
BES)。应用MISA 软件搜索获得SSR 位点4 732 个,平均每2.8 kb 出现1 个SSR。在含有单个SSR 的BES 中,1 ~3
个核苷酸重复的类型占SSR 总数的96.86%,A/ T、AT/ AT、ATT/ AAT 分别为最丰富的单核苷酸、2 核苷酸和3 核苷
酸重复。选择不同类型和重复次数的SSR 设计合成50 对引物,从中筛选出多态性引物33 对,其中19 对引物扩增
出1 或2 个等位基因,无非特异扩增产物。应用这19 对引物对20 份核桃属不同种的基因型进行SSR 分析,结果表
明,每对引物检测到2 ~9 个多态性位点,平均多态性位点5.4 个;其中17 个位点的多态信息含量高于0.5,总平均
值为0.662,多态性较高。聚类分析显示,不同基因型按照种属分类及地理起源分组。因此,BES-SSR 是一类多态
性高,可用于核桃属植物遗传分析的新SSR 引物。 相似文献
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苹果叶片再生的改进及抗虫基因植株的获得 总被引:5,自引:0,他引:5
用分别含有全部改造和部分改造的Bt基因植物表达载体pB48.7和pB48.6的土壤农杆菌转化苹果优良品种(红富士、早生富士、辽伏)的叶片外植体,经过对MS培养基成分调整,在Nt保持不变的条件下以(NH4):SO4取代NH4NO3,使得转化后再生频率大增,现已获得232株转化再生植株,这些植株可以在合50mg·L-1的卡那霉素培养基上生长,选出部分植株作PCR检测,表明Bt基因已被导入这些苹果品种中。 相似文献
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'Liaoning 2' is a dwarf walnut variety bred by Chinese scientists through artificial hybridization, but little is known about its dwarfing mechanism. In this study, the dwarfing mechanism of 'Liaoning 2' is discussed through the comparison of biological characteristics, genomics and the expression of growth-related gene JrGAI,with a growth normally, closely related(half-sib families) variety of 'Liaoning 1' as control. By observing the phenology and tree phenotypes, it was found that there was no significant difference in phenological phase between 'Liaoning 1' and 'Liaoning 2', but 'Liaoning 2' was obviously dwarf, the height, crown and trunk diameter were smaller, the average length of internode reduced significantly, but there was no significant difference in the number of development branch internode. The dwarf phenotype of 'Liaoning 2' is mainly caused by inter-shortening. The qRT-PCR technique was performed to analyze the expression of GA negative regulation gene JrGAI and the results showed that during the shoot development, the expression of JrGAI gene exhibited decreasing expression in the shoot rapid growing period in both varieties and the decline in 'Liaoning 1' was remarkably reduced. The SSR analysis with 25 pairs of primers showed that SSR loci of two varieties were different, especially the homozygosity of 'Liaoning 2' SSR loci was higher. It is concluded that different expressions of JrGAI gene and homozygosity of SSR loci could be important internal reasons of dwarf phenotype of 'Liaoning 2'. 相似文献
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核桃砧木新品种‘中宁强’ 总被引:1,自引:0,他引:1
核桃砧木新品种‘中宁强’是由美国引进的魁核桃(Juglans major)与河南省洛宁县核桃(Juglans regia L.)杂交选育而成。具有树干通直,根系发达,分枝力强,生长速度快,抗干旱,耐瘠薄,嫁接亲合力高等特点,年胸径生长量1.7 cm,为核桃的1.7倍。嫩枝扦插生根率85%,作砧木嫁接核桃品种的枝接成活率90%以上,芽接成活率95%,嫁接的核桃品种表现出生长势旺盛,坚果仁更加香甜。适宜在华北、西北、华东和西南核桃主产区应用。 相似文献
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用RAPD分析麻核桃起源与分类地位 总被引:16,自引:1,他引:15
利用随机扩增多态性DNA(RAPD)方法对麻核桃、核桃楸、核桃、奇异核桃和核桃×核桃楸的人工杂种进行了基因组多态性分析。选用28个10bp随机引物扩增出332个DNA片断,片断大小在259bp~3054bp之间,其中243个DNA片断呈现多态性,占总扩增片断的732%。依据扩增结果进行相似性系数和遗传距离分析,据此构建聚类树状图。研究结果表明:核桃楸×核桃的天然杂交是麻核桃形成的主要机制;在麻核桃形成过程中,核桃楸的遗传贡献率大于核桃;在胡桃属分类中,麻核桃应归为核桃楸组,这与传统分类学的结果一致。 相似文献