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31.
Restriction fragment length polymorphisms and genetic improvement of agricultural species 总被引：7，自引：0，他引：7
Evidence is accumulating demonstrating the ubiquity and abundance of a new class of genetic markers, restriction fragment length polymorphisms (RFLPs). These markers should allow the genetic map of agricultural species to be saturated in the near future. This holds great promise for useful applications, including: protection of breeder's rights, and more effective means for the characterization and manipulation of individual genetic loci affecting traits of economic importance.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No 768-E, 1985 series. Supported by the U.S.-Israel Agricultural Research and Development Fund (BARD). 相似文献
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分子探针在稻瘟病流行病学中的应用研究 总被引：14，自引：1，他引：13
】用重复序列探针ＭＧＲ５８６与限制性内切酶ＥｃｏＲ１组合,分别分析了我国１９８０～１９９７年在１７个省市１４６块稻田内外的１８６个不同水稻品种上采集的４４５个水稻分离菌株及２５种不同禾本科植物和杂草上采集的１０８个非水稻分离菌株的限制性片段长度多态性（ＲＦＬＰｓ）,依其ＭＧＲ－ＤＮＡ指纹的相似率,结合病菌的致病性测定,将表现为４８个不同致病型的５５３个菌株区分为５６个谱系。结果表明,稻瘟菌有远距离传播的可能性,并在适宜的气候和人工接种条件下,某些禾本科植物和杂草上的草瘟菌与稻瘟菌可彼此互交。这为稻瘟病的流行和预测提供了新的思路。该文用生物测定和分子生物学相结合的方法,揭示了我国在不同空间和时间的稻瘟菌群体存在着明显的遗传多样性及其流行因素,并对今后的抗病育种及其利用策略进行了讨论。 相似文献
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Stability of cassava plants at the DNA level after retrieval from 10 years of in vitro storage 总被引：2，自引：0，他引：2
Summary Cassava (Manihot esculenta Crantz) germplasm collections are conventionally maintained by continuous vegetative propagation in the field. Tissue culture techniques provide a more convenient way to conserve germplasm. The cassava in vitro gene bank held in trust at CIAT comprises nearly 6000 accessions. A study was carried out to determine whether any DNA rearrangements resulting from in vitro storage under slow growth could be detected by molecular analysis in retrieved plants. RFLPs with homologous probes, RAPDs with twenty primers and DNA fingerprinting with M13 probe were tested to detect variation at DNA level in cassava plants after ten-years in vitro storage. The molecular marker data obtained in this study supports the stability of the cassava germplasm under the in vitro storage conditions described in this work. 相似文献
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Genetic Diversity for RFLPs in European Maize Inbreds 总被引：31，自引：0，他引：31
J. Boppenmaier A. E. Melchinger G. Seiltz H. H. Geiger R. G. Herrmann 《Plant Breeding》1993,111(3):217-226
Restriction fragment length polymorphisms (RFLPs) have been proposed for predicting the yield potential of different types of cross. Their has been evaluated in 15 flint and 12 dent inbreds from the European maize (Zea mays L.) germplasm as well as in 68 F1 crosses (21 flint × flint, 14 dent × dent, and 33 flint × dent) produced between them. The materials were evaluated for F1 performance and midparent heterosis of grain yield, dry matter content (DMC) and plant height in two environments in Germany. Genetic distances (GDs) between parental lines, calculated from RFLP data of 194 clone-enzyme combinations, showed greater means for flint × dent (0.67) than dent × dent (0.62) and flint × flint (0.55) crosses. Cluster analysis based on GDs resulted in a clear separation of flint and dent lines and agreed well with pedigree information. For the complete set of 64 crosses analyzed (excluding 4 crosses between closely related lines) correlations of GD with F1 performance and heterosis were significant for all traits except F1 performance of DMC. When separate calculations were performed for individual subjets of crosses, correlations of GD with Fl performance and heterosis were significantly positive (0.48 ≤ r ≤ 0.80) for all traits in the flint × flint crosses, but not significant for the subsets of flint × dent and dent × dent crosses. Our results confirm those of previous investigations in that the predictive value of RFLP data is restricted to crosses between lines from the same heterotic group, and cannot be applied to crosses between lines from genetically divergent heterotic groups. 相似文献
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猪RYR1基因的检测及其对生产性能的遗传效应 总被引：14，自引：0，他引：14
本研究以PCR-RFLPs检测方法,分析了RYR1基因在山东省引进猪种及其杂交后代各群体中的分布.在纯种猪中,皮特兰猪的n基因的基因频率最高(100%),其次为长白猪(11.44%),再次为约克夏猪(6.68%),杜洛克和汉普夏猪为0;在杂种群体中,杜洛克×皮特兰猪最高(50%),长白×约克夏猪为10.62%,约克夏×长白猪为7.86%,约克夏×长白与长白×约克夏杂交所得的F2代为1.31%,杜洛克×汉普夏和汉普夏×杜洛克猪为0.利用最小二乘模型分析了RYR1基因对生产性能的遗传效应,结果表明RYR1基因对20日龄体重和60日龄体重的影响不显著(P＞0.05),但极显著提高日增重(P＜0.01).RYR1基因可极显著地提高猪的胴体瘦肉率,降低猪肉的肉色评分(P＜0.01).NN、Nn和nn3种基因型对瘦肉率和肉色评分的最小二乘均值分别为64.00%、66.87%、67.87%和2.73、2.57、2.02.在繁殖性状方面,RYR1基因对仔猪出生重影响不显著(P＞0.05),但显著降低繁殖母猪的产活仔数(P＜0.05),NN、Nn和nn3种基因型对产活仔数的最小二乘均值分别为11.16、10.00、8.26头. 相似文献
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Summary RFLPs were used to study the genetic relationships of 31 Portuguese coles (Brassica oleracea L.) representing the different ecotypes or landraces grown in Portugal. Other cole crops such as Jersey kale, Chinese kales, common cabbages, broccolis and cauliflower, two nine-chromosome wild species, and one accession of turnip also were included to determine the evolutionary relationships of Portuguese coles to other related coles. Principal coordinates and cluster analyses were conducted using a package of computer programs and RFLP data from 55 nuclear DNA probes, detecting 291 polymorphic restriction fragments. The results showed that the 48 accessions clustered into five groups: (a) a dispersed group with turnip and the wild brassicas; (b) Chinese kales; (c) broccolis and cauliflower; (d) a disperse group including Algarve and Jersey kales, thousand head kale, cabbages, and savoy cabbage; (e) a large and compact group containing all Portuguese tronchuda cabbages and kales. This unique and closely related group containing Portuguese tronchuda cabbages and kales could be further divided into five subgroups corresponding to the major areas of cultivation. The phenetic groupings of Portuguese tronchuda cabbages and kales based on RFLP data corresponded more with their geographic origins (collecting sites) than with their morphological similarities. A mechanism involving geographic isolation and frequent intercrossing within local areas is proposed to explain genetic relationships among Portuguese tronchuda cabbages and kales. 相似文献
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猪生长激素基因ApaⅠ酶切位点多态性分析 总被引：7，自引：0，他引：7
利用 PCR- RFL P技术 ,分析了大约克猪和长白猪 GH基因的 Apa 酶切位点多态性。结果表明 ,在p GH基因序列中共检测到 5种基因型和 4种等位基因 ;基因型频率和等位基因频率在 2个猪种间分布差异不显著。 相似文献
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Lucia Lioi Francesca Sparvoli Roberto Bollini 《Genetic Resources and Crop Evolution》1999,46(2):175-182
Variation of the lectin and the two lectin-related proteins, AIL (-amylase inhibitor-like) and ARL (arcelin-like) was examined in wild and cultivated accessions of Lima bean (Phaseolus lunatus L.) using electrophoresis of total seed proteins, immunoblot and RFLP analysis of lectin-related genes. Results confirm that divergence of the two major Lima bean gene pools, Andean and Mesoamerican, also apply to this protein family. All three members of the family are present in both gene pools, with differences in size, abundance and composition between gene pools, giving the possibility to distinguish Andean from Mesoamerican lectin pattern types. Both patterns show some variants, such as lack of lectin or its presence as an abundant protein. The observed variation reflects, at least in part, into genomic polymorphism. The presence of arcelin- and -amylase-related proteins in Lima bean could represent a tool to increase our knowledge in the evolution of the lectin family in Phaseolus species. 相似文献