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21.
长江水系中华绒螯蟹线粒体DNA的遗传多样性研究 总被引:3,自引:0,他引:3
本文对长江水系南京和江都地区中华绒螯蟹共61个个体的线粒体COI基因进行了限制性片段长度多态性(RFLP)分析。应用PCR技术扩增了中华绒螯蟹线粒体COI基因,选用8种能识别4碱基的限制性内切酶对该基因片段进行RFLP分析。在两个群体中共检测出8种复合单倍型,其中复合单倍型AAAAAAAA和BBBBBAAB为两个群体所共有,它的个体数所占的百分比在两个群体(南京和江都)中分别为87.9%、12.1%和50.0%、25.0%。在南京群体中,复合单倍型间的遗传距离为0.077,而在江都群体中,复合单倍型间的遗传距离为0.004~0.077;南京和江都群体的线粒体COI基因多态度(或称核苷酸多样性指数)π值分别为0.008和0.019。结果说明长江水系中华绒螯蟹具有一定的群体内遗传多样性。 相似文献
22.
浅色黄姑鱼线粒体16S rRNA基因片段序列特征分析 总被引:1,自引:0,他引:1
PCR扩增100个浅色黄姑鱼个体的线粒体16SrRNA基因片段序列,得到大约620bp的扩增产物。将其中5个个体的扩增产物进行测序和同源比对,得到468bp可供比对分析的片段。比对结果表明,5条序列包括两个单倍型,两个单倍型之间有1个碱基突变。PCR-RFLP分析结果显示,两个种群的100个样品中98%的个体为其中一种单倍型,只有2%的个体呈另一种单倍型,表明这两个种群的遗传多样性较低。两个单倍型平均碱基组成为:T22.0%,C26.3%,A29.8%,G21.9%,GC含量平均为48.2%。与GenBank中石首鱼科7属9种的11条同源序列比对,得到429个比对位点,其中包括69个简约信息位点、55个单突变子和16个插入/缺失位点。聚类分析显示,浅色黄姑鱼与黄姑鱼亲缘关系较近,与形态分类相符。 相似文献
23.
分子标记在植物上的应用 总被引:4,自引:0,他引:4
综述分子标记技术RFLP、RAPD、AFLP的基本原理、优缺点及其在植物研究中的应用情况。 相似文献
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Molecular mapping of an aluminum tolerance locus on chromosome 4D of Chinese Spring wheat 总被引:13,自引:0,他引:13
Summary The tolerance of aluminum (Al) of disomic substitution lines having the chromosomes of the D genome of Triticum aestivum L. cv. Chinese Spring individually substituted for their homoeologues in T. turgidum L. cv. Langdon was investigated by the hematoxylin method. The disomic substitution lines involving chromosome 4D were more Al tolerant than Langdon. The tolerance was found to be controlled by a single dominant gene, designated Alt2, that is in the proximal region of the long arm of chromosome 4D. The locus was mapped relative to molecular markers utilizing a population of recombinant chromosomes from homoeologous recombination between Chinese Spring chromosome 4D and T. turgidum chromosome 4B. Comparison of the location of Alt2 in this map with a consensus map of chromosomes 4B and 4D based on homologous recombination indicated that Alt2 is in a vicinity of a 4 cM interval delineated by markers Xpsr914 and Xpsr1051. The Alt2 locus is distal to marker Xpsr39 and proximal to XksuC2. The Altw locus is also proximal to the Knal locus on chromosome 4D that controls K+/Na+ selectivity and salt tolerance. In two lines, Alt 2 and Knal were transferred on a single 4D segment into the long arm of T. turgidum chromosome 4B. 相似文献
28.
M. J. gilpin R. A. pickering A. G. fautrier D. L. mcneil G. szigat A. M. Hill R. G. Kynast 《Plant Breeding》1997,116(6):505-510
Anther culture (AC) was carried out on a fertile triploid hybrid between Hordeum vulgare L. (cultivated barley) and H. bulbosum L, (bulbous barley grass) to determine whether AC-derived regenerants differed from progeny obtained through selfing and backcrossing. Chromosome counts were carried out on all plants and DNA was extracted from them to prepare Southern blots for molecular analysis. To identify true recombinants, the blots were probed with rye repetitive sequence probes (pSc119.1 and pScl19.2). which hybridize strongly and specifically to H. bulbosum DNA. Twenty probes that detect single- or low-copy sequences were hybridized with Southern blots containing restricted DNA extracted from 25 AC-derived plants, 11 selfed and six backcrossed progeny that showed hybridizations with pScll9. Although restriction fragment length polymorphisms (RFLPs) were only observed using probes that map to four of the possible 14 chromosome arms, an introgression associated with chromosome 6HS was frequently observed among plants derived from AC. selfing and backcrossing. Plants from AC differed from selfed and backcrossed progeny in their chromosome number; unique RFLP bands that were occasionally observed may indicate chromosomal rearrangements. 相似文献
29.
Summary A study was undertaken to evaluate the breeding behaviour and to identify a spontaneously produced putative chromosomal deletion in the winter wheat (Triticum aestivum L. em. Thell.) cv Norstar. Male and female transmission studies of plants heterozygous for the deletion chromosome indicated 9.5% and 48.8% transmission through the pollen and the egg, respectively. Meiotic analyses of progeny from deletion heterozygotes indicated that the deletion chromosome was eliminated from half of the plants, which agreed with the male and female transmission frequencies. Testcrosses of the deletion chromosome with telocentrics and nullisomic-tetrasomic combinations suggested that the deletion involved the long arm of chromosome 5D. This was confirmed by restriction fragment length polymorphism (RFLP) analysis. Also, monosomic plants obtained in progeny of deletion heterozygotes were shown to be monosomic for 5D. Studies of plants homozygous for the deletion showed relatively normal pairing between the deletion chromosomes, and with the short arm (5DS), but not the long arm (5DL). Deletion homozygotes were self-sterile, and morphologically similar to plants nullisomic for 5D, but plants that also contained 5DL, or a homoeologous chromosome were self-fertile and had normal morphology. Studies of chromosome morphology indicated that the deletion chromosome was metacentric, and the length of the long arm was reduced by approximately 60%. RFLP studies showed that, in terms of genetic distance, 90% of the arm was missing. 相似文献
30.
Genetic diversity within Australian wheat breeding programs based on molecular and pedigree data 总被引:8,自引:0,他引:8
124 wheat cultivars and breeding lines were screened with 19 microsatellite (SSR) loci generating 160 scorable bands which
were used to construct a genetic distance (GD) matrix. A distance matrix based on coefficient of parentage (COP) scores was
also generated for the cultivars for which good pedigree records were available. The SSR and COP data for 101 of the wheat
cultivars were compared with genetic distance scores obtained using1898 scorable restriction fragment length polymorphism
(RFLP) bands previously generated. Phylograms were generated based on the SSR, RFLP,combined SSR and RFLP and COP data. The
standardised Mantel's Z test showed that the distance matrices generated from all of the data sets were significantly correlated.
Bootstrap analysis showed that, although the SSR and RFLP data were correlated, a large number of SSR loci are required for
determining robust genetic relationships between large numbers of cultivars. In addition, accurate pedigree records are needed
to determine genetic relatedness using COP. The molecular data were also used to determine the level of genetic variability
within breeding programs and to assess the impact of the introduction of semidwarf and other germplasm. The results showed
that the level of genetic diversity in Australian wheat cultivars has increased over time and that in particular, the introduction
of semidwarf germplasm resulted in an increase in the overall diversity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献