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61.
吕晶  刘凡  宗梅  韩硕  王幼平  王桂香 《园艺学报》2014,41(3):456-468
 以花椰菜—黑芥体细胞杂种自交及回交后代为材料,结合形态学特征,分子标记和荧光原 位杂交(FISH)等群体分析技术,在16 份高代回交及自交材料中筛选获得了花椰菜类型渐渗系材料12 份,偏花椰菜类型异附加系材料4 份。形态学调查及FISH 分析表明:12 份渐渗系材料除茎、叶等营养器 官特征与花椰菜近似外,已具有较正常的花球形成,染色体数为18 条,均来源于花椰菜;植株花粉母细 胞减数分裂行为基本正常。SSR 和AFLP 分子标记检测表明,渐渗系材料除扩增到数量不等的黑芥多态 性位点外,还扩增到埃塞俄比亚芥特异的多态性位点和少量新位点,另外发现渐渗系材料有丢失亲本花 椰菜多态性位点的现象。FISH 分析4 份异附加系材料的染色体组成,结果显示:PFCN29BC2S1-4 为9 条 花椰菜染色体附加8 条黑芥染色体;PFCN15-2S1BC5-6-2 和PFCN29BC4-37-7 为16 条花椰菜染色体分别 附加7 条和14 条黑芥染色体;PFCN29BC4-38-5 为花椰菜染色体附加了5 ~ 7 条黑芥染色体。  相似文献   
62.
FISH 技术在芸薹属作物基因组研究中的应用进展   总被引:1,自引:0,他引:1  
 FISH 技术是进行基因和重复DNA 序列在染色体上可视化作图的精确有效方法,已广泛应用于特异核苷酸序列的物理作图、基因组或染色体的识别、DNA 序列的定量分析以及着丝粒、染色质空间结构分析等方面。综述了FISH 技术在芸薹属作物基因组研究中的重要进展,并讨论了其应用前景。  相似文献   
63.
本文报导了对茶树鱼叶生理功能研究的初步结果。研究证明:鱼叶比同枝邻位真叶,光合作用功能无明显差异;鱼叶的呼吸强度低于真叶;新梢采摘后留下的鱼叶和邻位叶比,其光合值显著高于真叶。鱼叶的生化内含物除多酚类外,氨基酸、咖啡碱均高于真叶。鱼叶的气孔开张度低于真叶,最大开启度在下午16时,而真叶在上午10时。表明:鱼叶不是非正常叶,而是一种生理功能叶。  相似文献   
64.
Peanut diseases seriously threaten peanut production, creating disease-resistant materials via interspecific hybridization is an effective way to deal with this problem. In this study, the embryo of an interspecific F_1 hybrid was obtained by crossing the Silihong(Slh) cultivar with Arachis duranensis(ZW55), a diploid wild species. Seedlings were generated by embryo rescue and tissue culture. A true interspecific hybrid was then confirmed by cytological methods and molecular markers. After treating seedlings with colchicine during in vitro multiplication, the established interspecific F_1 hybrid produced seeds which were named as Am1210. With oligonucleotide fluorescence in situ hybridization(Oligo FISH), molecular marker evaluations, morphological and web blotch resistance characterization, we found that: 1) Am1210 was an allohexaploid between Slh and ZW55; 2) the traits of spreading lateral branches, single-seeded or double-seeded pods and red seed coats were observed to be dominant compared to the erect type, multiple-seeded pods and brown seed coats; 3) the web blotch resistance of Am1210 was significantly improved than that of Slh, indicating the contribution of the web blotch resistance from the wild parent A. duranensis. In addition, 69 dominant and co-dominant molecular markers were developed which could be both used to verify the hybrid in this study and to identify translocation or introgression lines with A. duranensis chromosome fragments in future studies as well.  相似文献   
65.
中国水仙3个特异种质的分子细胞遗传学分析   总被引:1,自引:0,他引:1  
 应用荧光原位杂交技术进行rDNA在黄花水仙和两色花水仙染色体上的定位研究,并分析了两色花水仙的基因组成。结果表明:不同材料的NOR位点表现出多态性,即黄花水仙上具3个45S rDNA位点,两色花水仙具有5个位点;5S rDNA在位点和数量上表现出一致性。基因组荧光原位杂交结果表明两色花水仙的染色体有10条来自于黄花水仙,22条来自于白花水仙。根据rDNA在这些种质资源上的分布,结合GISH技术的分析,证实两色花水仙是黄花水仙和白花水仙的天然杂交种。  相似文献   
66.
Gastric Helicobacter spp. are associated with chronic inflammation and neoplastic transformation in humans as well as domestic and laboratory species. The present study examined the association of Helicobacter heilmannii (Hhe) infection in pet cats with feline gastric mucosa associated lymphoid tissue (MALT) lymphoma. Tissues were collected via gastric biopsy or at necropsy from 47 pet cats with clinical signs of gastrointestinal disease, including vomiting and inappetance, and classified as gastritis (14/47), lymphoma (31/37), or normal (2/47). Tissues positive for argyrophilic organisms with Warthin–Starry stain (29/47) were assessed by fluorescent in situ hybridization (FISH) for the presence of Hhe strains 1–4 as well as with a fifth probe that detected Helicobacter salomonis, Helicobacter bizzozeronii, or Helicobacter felis. A significant association of positive Warthin–Starry status with Hhe infection was found in cases of sick cats (22/29; p < 0.05 by Chi-square; χ2 = 7.034). Interestingly, a significant association between Hhe status and a diagnosis of lymphoblastic or lymphocytic lymphoma was observed as well in a subset of 24 Warthin–Starry positive lymphoma cases: of lymphoblastic lymphoma cases, 13/17 were positive for Hhe (p < 0.05; χ2 = 4.854). Hhe strains 2 and 4 were most commonly found (18/29 and 17/29, respectively) among sick cats, although a higher than expected number of cats was also positive for Hhe1, which initial reports have described as rare in cats and common in humans. The association found between a positive Hhe status with the presence of feline gastric lymphoma, especially lymphoblastic lymphoma, argues for the need to conduct prospective studies to better identify the frequency and strain distribution of Hhe infection in both healthy and clinically ill cats, particularly those cats with gastric lymphoma.  相似文献   
67.
In this study, multicolor fluorescence in situ hybridization (FISH) analysis on metaphase chromosomes of spinach with biotin-labeled 25S rDNA, DIG-labeled telomere sequences and biotin-labeled and DIG-labeled 5S rDNA was performed. There were six 25S rDNA loci located on the satellites of the third, the fifth and the sixth chromosomes, and four 5S rDNA loci located on the long arms of the third and the fifth chromosomes. The telomere loci were located on the end of the sixth chromosome and also on both the end and centromeric regions of other chromosomes. This study is an important complement to both traditional karyotype analysis and FISH karyotype analysis in spinach. __________ Translated from Hereditas (Beijing), 2007, 29(11): 1405–1408 [译自: 遗传(北京)]  相似文献   
68.
This report concerns the cytogenetic analysis, using both C‐banding and fluorescence in situ hybridisation techniques, of a sterile mare. Results obtained revealed a 2n = 65, XXX condition with no sign of mosaicism. The work supports the suggestion that X trisomy, rare in horse, causes infertility in mares and is not associated to other clearly visible phenotypic features.  相似文献   
69.
采用化学和萌发两种预处理方法,对多粘芽孢杆菌SQR21芽孢进行荧光原位杂交(FISH),结合扫描电镜比较不同预处理芽孢表面结构和形态变化。结果表明,两种预处理均可在2 h内完成SQR21芽孢的荧光原位杂交,且萌发预处理比化学预处理杂交效率高,荧光信号强。扫描电镜结果显示,萌发预处理芽孢无裂解,而化学预处理芽孢有不同程度的裂解。将萌发预处理荧光原位杂交用于检测猪粪有机肥中二次发酵的SQR21芽孢,发现在37℃,含水量50%的条件下,2 h后芽孢开始生长,4 h后营养体细胞出现,12 h后营养体细胞有显著优势。本研究建立的芽孢荧光原位杂交检测技术,比平板计数更能准确反映多粘芽孢杆菌芽孢的数量和生长动态,在生物有机肥中芽孢杆菌的检测方面有良好的应用前景。  相似文献   
70.
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