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71.
为明确小麦品种西农979对赤霉病的抗性遗传基础,以西农979和苏麦3号构建的F2代群体以及西农979的主要供体亲本为材料,利用与苏麦3号3BS染色体上Fhb1基因紧密连锁的2对SSR引物及其共分离特异性标记引物UMN10进行检测,并调查西农979大田赤霉病抗性。结果表明,引物Xgwm533、Xgwm493及UMN10对西农979、苏麦3号及西农979/苏麦3号构建的F2群体(510个单株)扩增结果均为单态,表明西农979具有苏麦3号3BS上的Fhb1基因位点。对西农979的主要供体亲本的分子标记及亲缘关系分析,进一步表明西农979具有苏麦3号的抗赤霉病基因,其Fhb1基因位点来源于西农881,这可能是西农979对小麦赤霉病表现为中抗或中感且抗性较为稳定的遗传基础。 相似文献
72.
传统的叶绿体基因分子标记在茶组植物分类系统研究中的应用价值相对有限,为了筛选可用于茶树鉴别与母系溯源的SNP(单核苷酸多态性)位点组合,将18个已报道的茶组植物叶绿体全基因组序列进行比对,通过设计通用引物,在169个茶树品种/品系中进行候选分子标记扩增与一代测序分析,筛选出16对引物,共含25个SNP位点可用于茶树品种母系溯源与鉴别分析。另外,将SNP位点组成的DNA指纹图谱结合茶树品种资源基本信息进行数字编码,最终形成由30位数字组成的茶树品种资源分子身份证,并构建相应的条形码和二维码用于品种识别。本研究数据为茶树品种的母本溯源与鉴别提供新的思路。 相似文献
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LIU Ze-guang YAO Wei-yuan SHEN Xue-xue CHAO Kai-xiang FAN Yu LI Min-zhou WANG Bao-tong LI Qiang JING Jin-xue 《中国农业科学(英文版)》2014,(12):2577-2583
Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating diseases of wheat throughout the world. H9020-1-6-8-3 is a translocation line originally developed from interspeciifc hybridization between wheat line 7182 and Psathyrostachys huashanica Keng and is resistant to most Pst races in China. To identify the resistance gene(s) in the translocation line, H9020-1-6-8-3 was crossed with susceptible cultivar Mingxian 169, and seedlings of the parents, F1, F2, F3, and BC1 generations were tested with prevalent Chinese Pst race CYR32 under controlled greenhouse conditions. The results indicated that there is a single dominant gene, temporarily designated as YrH9020a, conferring resistance to CYR32. The resistance gene was mapped by the F2 population from Mingxian 169/H9020-1-6-8-3. It was linked to six microsatellite markers, including Xbarc196, Xbarc202, Xbarc96, Xgpw4372, Xbarc21, and Xgdm141, lfanked by Xbarc96 and Xbarc202 with at 4.5 and 8.3 cM, respectively. Based on the chromosomal locations of these markers and the test of Chinese Spring (CS) nullitetrasomic and ditelosomic lines, the gene was assigned to chromosome 6D. According to the origin and the chromosomal location, YrH9020a might be a new resistance gene to stripe rust. The lfanking markers linked to YrH9020a could be useful for marker-assisted selection in breeding programs. 相似文献
76.
[目的]通过降低试验药剂、减少PCR循环时间、提高琼脂糖利用指数等,建立经济、快速、低污染的杂交水稻纯度鉴定体系。[方法]将杂交水稻万优481、亲本万3A和万恢481在光照培养箱内温度发芽(30℃,长到5 cm左右),用CTAB法提取DNA;按优化的PCR体系和电泳方法,用亲本万3A和万恢481的DNA从24对引物中筛选出多态性好的引物P18,用引物P18对杂交水稻万优481样本进行纯度鉴定。[结果]利用优化的SSR分子标记技术准确鉴定出万优481的纯度为98.5%,与田间鉴定结果相符,凝胶电泳成像带谱清晰,同时,与常用方法相比,酶等试验药品使用量减少20%~25%,试验所用时间较常用方法减少了50%以上。[结论]利用优化的SSR分子标记技术体系鉴定杂交水稻种子纯度,经济、快速且鉴定的结果清晰、可靠,同时大大减少琼脂糖等试验残渣的产生,降低了对环境污染,值得推广、应用。 相似文献
77.
SSR分子标记在玉米品种真实性鉴定上的应用 总被引:1,自引:0,他引:1
跟田间种植鉴定相比,SSR 分子标记鉴定品种真实性具有快速、准确、不受环境影响等特点,是打击套
牌侵权、维护品种权人合法权益的有效途径。利用20 对核心引物对玉米品种进行真实性鉴定,有9 对核心引物扩增
产物出现明显差异,11 对核心引物扩增产物没差异,表明利用SSR 分子标记鉴定玉米品种真实性是可行的。 相似文献
78.
Marta Novo Ana Almodóvar Rosa M. Fernández Mónica Gutiérrez Darío J. Díaz Cosín 《Pedobiologia》2010,53(6):375-379
Endogeic earthworms are difficult study subjects due to the cryptic medium in which they live; thus, only the behaviour of epigeic and anecic earthworms has been studied before. We used microsatellite markers as a tool to elucidate the mate choice processes of Hormogaster elisae, an endogeic earthworm. It was shown to normally mate with two partners, preferably of the same size that are found in close proximity thereby eliminating the need for long-distance dispersion, which could explain the previously observed high genetic differentiation between populations. The genetic analyses of the sperm within each of its four spermathecae showed a uniform distribution with no signs of differential storage of sperm from different partners. 相似文献
79.
Chemical taxonomy based upon the composition of lipids is widely applied to investigate microbial communities and fatty acids have recently been employed to connect soil microbial and faunal food webs as well as to elucidate functional groups at higher trophic levels. The additional use of compound-specific isotopic analysis of 13C/12C ratios in fatty acids allows assessing specific trophic links and belowground carbon fluxes. In this review systematic patterns and processes underlying variations in the composition of fatty acids and their 13C/12C ratio are described. The emphasis is on biomarker fatty acids, their incorporation and modification, effects of pool size, and analytical methods. Further development of the application of fatty acid profiling to soil ecology should include both advances in experimental research and growth of theory. Accordingly, areas in which future experimentation can lead to progress in soil food web analysis are identified. Overall, combining fatty acid biomarker and their isotopic ratios will allow detailed insight into belowground trophic interactions. 相似文献
80.
Immunohistochemical characterization of canine prostatic carcinoma and correlation with castration status and castration time 总被引:2,自引:0,他引:2
K. U. Sorenmo M. Goldschmidt F. Shofer C. Goldkamp J. Ferracone 《Veterinary and comparative oncology》2003,1(1):48-56
The purpose of this study was to characterize canine prostate cancer using immunohistochemical staining specific for acinar and urothelial/ductal tissue and correlate these results with the dogs' castration status/castration time. Seventy dogs with prostate cancer were included, 71% were castrated and 29% were intact. Compared with an age‐matched control population, castrated dogs were at increased risk of prostate cancer, odds ratio 3.9. Immunohistochemical staining was performed on 58 cases. Forty‐six of the 58 stained positive for cytokeratin 7 (CK 7) (ductal/urothelial origin) and one of the 58 stained positive for prostate‐specific antigen. Dogs with CK 7‐positive tumours were younger when castrated than dogs with CK 7‐negative tumours, 2 versus 7 years (P = 0.03); dogs castrated at ≤2 years of age were more likely to be CK 7‐positive (P = 0.009). These results show that most canine prostatic carcinomas are of ductal/urothelial, androgen‐independent origin. This is consistent with the epidemiological findings, showing increased risk in castrated dogs. Canine prostate cancer may, therefore, not be a realistic model for the human disease. 相似文献