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选用草原红牛30头作为试验牛群体,经过牛血液基因组DNA的提取、8对微卫星引物的PCR扩增、扩增产物的聚丙烯酰胺电泳分型、计算机凝胶成像分析系统分析各位点等位基因及全部个体的标记基因型、PPAP3.0软件计算基因频率、多态信息含量(PIC)和杂合度等步骤从分子水平上分析了草原红牛在8个位点的遗传多态性。结果表明,IDVGA2、IDVGA46、TGLA44、BM1824、ETH225、BM2113、IDVGA44和IDVGA55等位基因数分别为6、6、6、4、4、2、6和4,多态信息含量分别为0.722 3、0.749 3、0.671 3、0.584 9、0.671 5、0.508 9、0.761 2和0.596 5,这8个位点均为高度多态位点。8个位点作为遗传标记应用于草原红牛遗传育种研究是可行的。 相似文献
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采用磁珠富集法分离刺参Apostichopus japonicus的微卫星分子标记,共获得阳性克隆123个,其中106个含微卫星DNA序列。分析结果表明:完美型有48个,占45.28%,非完美型有39个,占36.79%,复合型有19个,占17.92%;重复碱基数以双核苷酸重复最常见,占84.91%,双核苷酸中又以CA/GT重复所占比例最大;在重复次数方面,以重复数为3~10次、11~18次和≥35次最为常见,各占39.62%、26.42%和16.98%,重复数达100次以上的有5个,最多的达到148次,有28个微卫星序列微卫星含量丰富。筛选的22对引物中,可产生出扩增产物的有17对,其中16对引物的产物带在预测区域内出现;有7对引物在中国、俄罗斯刺参模板中表现出多态性。文中还对刺参微卫星的特点进行分析,对刺参微卫星引物的PCR筛选结果进行了探讨。 相似文献
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Ravindra DONDE Jitendra KUMAR Gayatri GOUDA Manoj Kumar GUPTA Mitadru MUKHERJEE Sk Yasin BAKSH Pradosh MAHADANI Khirod Kumar SAHOO Lambodar BEHERA Sushanta Kumar DASH 《水稻科学》2019,26(4):239-247
The introgression of wild chromosomal segments into popular rice varieties is one of the potential approaches for developing varieties for drought stress condition. Sixteen genotypes, including nine indica, two tropical japonica and five chromosome segments substitution lines(CSSLs) with different levels of tolerance/susceptibility to drought stress, were selected for diversity study. Sixty-three microsatellite markers were utilized for assessing genetic diversity. A total of 95 alleles were amplified, and out of them, 60 were polymorphic. Six unique alleles, amplified by the microsatellite loci RM276, RM472,RM488, RM537, RM541 and RM28089, were identified in six genotypes, namely FR13A, Brahamanakhi,RUF44, Swarna-sub1, Brahamanakhi and Satyabhama. The highest genetic similarity was found among CSSLs. Polymorphism information content(PIC) value varied from 0 to 1.00 with an average of 0.66 per locus. Twenty-eight microsatellites were found to be polymorphic, which could be used in marker-assisted selection programme. All the sixteen genotypes were grouped into two major clusters at genetic similarity of 0.64. In the cluster I, five CSSLs identified as diverse genotypes had wild ancestor segments responsible for drought tolerance, and hence they could be utilized as potential donors. The popular Indian varieties, Swarna-sub1 and IR64-sub1, could be used as recurrent parents in the future breeding program for developing varieties for abiotic stresses such as submergence and drought. 相似文献
47.
Abderrazek Jilal Stefania Grando Robert J. Henry L. Slade Lee Nicole Rice Helen Hill Michael Baum Salvatore Ceccarelli 《Genetic Resources and Crop Evolution》2008,55(8):1221-1230
Twenty genic- and genomic SSR markers were used to study genetic diversity and geographical differentiation of barley from 29 countries through analysis of a worldwide collection of 304 ICARDA’s barley landraces. Of these, 19 loci were highly polymorphic in the material studied. Based on Nei-distance matrix, Principal Component Analysis (PCoA) and cluster analysis using UPGMA associated with AMOVA the data revealed countries’ grouping within regions. Three distinct germplasm pools were identified in the landraces. The first of these was from Eastern Africa (Eritrea and Ethiopia) and South America (Ecuador, Peru and Chile) suggesting that barley introduced to South America might have originated specifically from East Africa or that they share a common genetic basis for adaptation. The second was the Caucasus (Armenia and Georgia) and the third included the remaining regions of Central Asia, Near East, Northern Africa and Eastern Asia. Genetic diversity of barley subspecies (Six-rowed barley, Two-rowed barley, H. spontaneum C. Koch and H. agriocrithon Åberg) also discriminates them into three groups: cultivated barleys (Six-rowed barley and Two-rowed barley), wild barley H. spontaneum and subspecies H. agriocrithon. These results associated with parsimony analysis demonstrate that H. agriocrithon and H. spontaneum might be distinct and do not support a hybrid origin for H. agriocrithon suggesting further investigation of the basis of more intense sampling of the two subspecies H. spontaneum and H. agriocrithon. 相似文献
48.
3微卫星标记的应用自微卫星被发现以来就受到了家畜遗传育种家们的高度重视,并且充分认识到了把它作为畜种的基因组变异研究所具有的巨大的潜在价值。现在它已被十分成功地作为富含信息、又容易获得的基因标记,广泛用于构建物种的遗传连锁图,基因鉴定(基因诊断)、物... 相似文献
49.
Wei Song Hao Xie Qing Liu Chaojie Xie Zhongfu Ni Tsomin Yang Qixin Sun Zhiyong Liu 《Euphytica》2007,156(1-2):95-102
The traditional process of obtaining maize hybrids involves the generation of inbred lines through successive generations
of selfing and subsequent testcrosses in order to identify the best combining ability by allelic complementation. A fast alternative
to obtain inbred lines is to induce the formation of haploids followed by chromosome doubling. However, even with the aid
of haploid-inducing genetic sources, this strategy has not been widely used in maize breeding programs, partly due to difficulties
inherent to haploid generation and identification. In order to evaluate the possibility of using dihaploids to generate homozygous
maize tropical lines, we used the androgenetic haploid inducer line W23 as a female parent in crosses with the tropical single-cross
hybrid BRS1010. Within the progeny of these crosses, 462 seeds were phenotypically selected as putative haploids by the purple-colored
endosperm and colorless embryo conditioned by the R1-nj gene. Among these, only four individuals were confirmed as being haploids using SSR markers, chromosome counting and flow
cytometry, showing that the phenotypic marker was not efficient in detecting haploids in the tropical maize genotype used.
All four haploids as well as some diploid plants presented reduced size, corroborating the difficulties for haploid identification
by phenotypic evaluation. Genetic diversity analysis revealed by SSR markers divided the haploids in two groups represented
by flint and dent maize inbred lines, which could be helpful in identifying complementary dihaploid lines. The present article
demonstrates that a combination of haploid production and SSR fingerprinting is a feasible strategy for maize hybrid development
in tropical germplasm. 相似文献
50.
棉花微卫星DNA扩增产物检测方法的优化研究 总被引:1,自引:0,他引:1
以棉花两个多标记基因系F582和F586及其后代为材料,对微卫星DNA的PCR扩增产物检测方法进行了优化研究。结果表明:检测微卫星DNA,聚丙烯酰胺银染灵敏度高于琼脂糖EB染色;聚丙烯酰胺凝胶的浓度需随着待测SSR序列的片段大小而作适当调整,一般情况下聚丙烯酰胺凝胶的浓度以6%为宜,但当待检测的DNA片段小到100bp~250bp的区域范围时,凝胶的浓度需提高到8%。胶板样品上样量以3μl为宜。在显色液预冷(约10℃)的前提下,显色的时间应控制在4min之内,以便得到的胶板DNA条带强度适中、对比度好。 相似文献