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971.
972.
陕西大豆资源遗传多样性及变异特点研究 总被引:2,自引:0,他引:2
利用42个PAPD引物对75份陕西大豆种质进行遗传多样性分析,共扩增出310个条带,平均每个引物扩增7.3个条带,多态性比率为96%;田间试验考察了13个农艺性状。陕西大豆的遗传多样性在秦岭南、北两个地区有所不同,秦岭北品种遗传多样性指数较高的性状数目和性状遗传多样性指数都大于秦岭南品种,RAPD分子标记遗传多样性指数也是秦岭北品种大于秦岭南品种,但秦岭南品种RAPD分子标记的遗传多样性指数较高的个数大于秦岭北品种。聚类分析将参试大豆材料分为三大类,基本上反映了材料的地理来源。主成分分析结果显示,前两个主成分反映了10.95%的遗传变异,基于前两个主成分值的二维散点图可以将两个地区的材料基本区分开来。AMOVA分析显示,陕西大豆品种个体间的遗传变异占总变异的92.06%,地区间的遗传变异占总变异的7.94%,二者都达到了极显著水平。研究结果表明,陕西大豆资源存在丰富的遗传多样性,秦岭北品种遗传多样性较高,但秦岭南品种有着广泛的微小变异。 相似文献
973.
谷子地方品种和育成品种的遗传多样性研究 总被引:5,自引:1,他引:4
田伯红 《植物遗传资源学报》2010,11(2):224-228
对河南、河北和山东等地的482份谷子地方品种和近30年培育的谷子品种的11个形态性状和农艺性状进行种植观察,研究两类品种的遗传多样性。与地方品种相比,育成品种形态性状的多样性指数大多低于地方品种,育成品种的株高比地方品种显著降低,稳重、穗粒重和出谷率等性状显著提高。地方品种的广泛变异类型是现代谷子育种的重要遗传资源。 相似文献
974.
Bandamaravuri Kishore Babu S. S. Reddy Mukesh K. Yadav M. Sukumar Vijendra Mishra A. K. Saxena Dilip K. Arora 《Indian journal of microbiology》2010,50(2):199-204
Genetic diversity analysis of Macrophomina phaseolina isolates obtained from different host range and diverse geographical locations in India was carried out using RAPD fingerprinting.
Of the thirteen 10-mer random primers used, primer OPB-08 gave the maximum polymorphism and the UPGMA clustering could separate
50 isolates in to ten groups at more than 65% similarity level. The ten clusters correlated well with the geographical locations
with exceptions for isolates obtained from Eastern and Western Ghats. There was a segregation of isolates from these two geographical
locations in to two clusters thus, distributing 10 genotypes in to eight geographical locations. All the isolates M. phaseolina irrespective of their host and geographical origin, exhibited two representative monomorphic bands at 250 bp and 1 kb, presence
of these bands suggests that isolates might have evolved from a common ancestor but due to geographical isolation fallowed
by natural selection and genetic drift might have segregated in to subpopulations. Genetic similarity in the pathogenic population
reflects the dispersal of single lineage in all locations in India. 相似文献
975.
Jean-Jacques Kupiec 《Progress in biophysics and molecular biology》2010,102(1):45-52
It is now widely recognized that gene expression and cellular processes include a probabilistic component. However, this does not essentially modify the theory of genetic programming. This stochastic aspect, which is called noise, is usually conceived as a margin of fluctuation in the way the genetic program functions and the latter remains understood as a specific mechanism guided by genetic information. In contrast, recent data show that proteins do not possess a high level of specificity. They can interact with numerous molecular partners. As a consequence molecular interactions are not simply “noisy”. Because they are subject to large combinatorial interaction possibilities, they are also intrinsically stochastic and must be sorted out by the cell structure. This contradicts the genetic programming theory which is based on the idea that protein interactions are directed by their stereospecificity and genetic information. Taking into account the lack of protein specificity leads to a new theory. Natural selection acts not only in evolution but also in ontogenesis by sorting stochastic molecular interactions. In this frame, the making up of an organism, instead of being a simple bottom-top process in which information flows from genes to phenotypes, is both a bottom-top and top-bottom process. Genes provide proteins, but their stochastic interactions are sorted by selective constraints arising from the cell and multi-cellular structures, which are themselves subject to the action of natural selection. 相似文献
976.
A. Castillo H. Budak A.C. Martín G. Dorado A. Börner M. Röder P. Hernandez 《The Annals of applied biology》2010,156(3):347-356
A selection of 147 wheat D-genome and 130 barley genomic simple sequence repeat (gSSR) markers were screened for their utility in Hordeum chilense, as an alien donor genome for cereal breeding. Fifty-eight wheat D-genome and 71 barley PCR primer pairs consistently amplified products from H. chilense. Nineteen wheat D-genome and 20 barley gSSR markers were polymorphic and allowed wide genome coverage of the H. chilense genome. Twenty-three of the wheat D-genome and 11 barley PCR primer pairs were suitable for studying the introgressions of H. chilense into wheat, amplifying H. chilense products of distinct size. In 88% of the markers tested, H. chilense products were maintained in the expected homeologous linkage group, as revealed by the analysis of wheat/H. chilense addition lines. Twenty-nine microsatellite markers (eight gSSRs and 21 expressed sequence tags-SSRs) uniformly distributed across the genome were tested for their utility in genetic diversity analysis within the species. Three genetic clusters are reported, in accordance with previous morphological and amplified fragment length polymorphism data. These results show that it is possible to discriminate the three previously established germplasm groups with microsatellite markers. The reported markers represent a valuable resource for the genetic characterisation of H. chilense, for the analysis of its genetic variability, and as a tool for wheat introgression. This is the first intraspecific study in a collection of H. chilense germplasm using microsatellite markers. 相似文献
977.
El-Armouche A Wahab A Wittköpper K Schulze T Böttcher F Pohlmann L King SB DuMond JF Gerloff C Böger RH Eschenhagen T Carrier L Donzelli S 《Biochemical and biophysical research communications》2010,397(2):340-344
Haplotype, which is the sequence of SNPs in a specific chromosome, plays an important role in disease association studies. However, current sequencing techniques can detect the presence of SNP sites, but they cannot tell which copy of a pair of chromosomes the alleles belong to. Moreover, sequencing errors that occurred in sequencing SNP fragments make it difficult to determine a pair of haplotypes from SNP fragments. To help overcome this difficulty, the haplotype assembly problem is defined from the viewpoint of computation, and several models are suggested to tackle this problem. However, there are no freely available web-based tools to overcome this problem as far as we are aware. In this paper, we present a web-based application based on the genetic algorithm, named HapAssembler, for assembling a pair of haplotypes from SNP fragments. Numerical results on real biological data show that the correct rate of the proposed application in this paper is greater than 95% in most cases. HapAssembler is freely available at http://alex.chonnam.ac.kr/~drminor/hapHome.htm. Users can choose any model among four models for their purpose and determine haplotypes from their input data. 相似文献
978.
Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 (1): 57-64 2010]. 相似文献
979.
980.