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生物性状遗传标记研究进展 总被引：1，自引：0，他引：1
赵荣乐 《喀什师范学院学报》2003,24(3):62-65,83
遗传标记技术是生物优良品种培育中筛选原始育种材料的关键技术，近二十年来，此项技术取得了快速发展，在生物性状的遗传标记的研究方面取得了许多成果。 相似文献
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食用型甘薯数量性状遗传参数对单株鲜薯产量选择效果的研究 总被引：4，自引：0，他引：4
估算了食用型甘薯7个数量性状的主要遗传参数。结果表明，性状之间遗传力存在较大差异。应据此掌握不同性状的选择标准。单株大中薯率遗传力高，与鲜薯产量遗传相关密切，由该性状参与的指数方程选择效率高，是相关选择的关键性状，对鲜薯产量的直接选择也给予足够重视。食用型甘薯育种应用选择指数方法进行综合选择，比直接选择鲜薯产量相对效率提高3．19－192．65个百分点，具有较高的应用价值。 相似文献
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玉米自交系的主要数量性状配合力效应分析 总被引：2，自引：0，他引：2
试验将Ｇｒｉｆｆｉｎｇ方法４。研究了玉米自交系１０个主要数量性状的配合力参数。结果表明：基因性效应在杂种后代的遗传中占有较大的遗传份量；在杂交种配制时应选择以亲的一般配合力都高，或者亲本之一的一般配合力较设期获得较高产量的杂交种；配合力总产应是产量育 决定性因素。 相似文献
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黄中文 《河南科技学院学报》2006,34(2):8-11
随着分子生物学理论与技术的进步，对杂种优势的遗传机理近年开展很多研究。本文综述了杂种优势研究的遗传基础的国内外最新研究进展。应用分子标记研究已经为经典的显性和超显性假说找到新的证据。植物数量性状的上位性研究也为揭示杂种优势表达的遗传机理提供了卓有成效和证据。 相似文献
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介绍了生物分子标记技术的概念及其分类，以及在植物遗传多样研究、亲缘关系分析、数量性状的基因定位与遗传图谱构建、品种改良及分子标记辅助育种等研究中的应用与现状，提出了当前分子生物学技术在植物资源保存、繁殖、利用研究应用中存在的问题及解决途径． 相似文献
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在高中遗传内容学习过程中，许多学生错误地认为：只要是常染色体遗传，杂交后代性状分离比就一定与性别无关；只要杂交后代性状分离比与性别无关，就一定是常染色体遗传。其实，常染色体遗传的杂交后代性状分离比不一定与性别无关，杂交后代性状分离比与性别无关的遗传也不一定是常染色体遗传。现分别加以说明。 相似文献
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估算了食用型甘薯7个数量性状的主要遗传参数.结果表明,性状之间遗传力存在较大差异,应据此掌握不同性状的选择标准.单株大中薯率遗传力高,与鲜薯产量遗传相关密切,由该性状参与的指数方程选择效率高,是相关选择的关键性状.对鲜薯产量的直接选择也应给予足够重视.食用型甘薯育种应用选择指数方法进行综合选择,比直接选择鲜薯产量相对效率提高3.19～192.65个百分点,具有较高的应用价值. 相似文献
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张伟伟 《廊坊师范学院学报(自然科学版)》2010,10(4)
人类群体遗传学着重于实际调查,即对各个人群的各种性状与遗传标记进行调查,调查一般以取样方式进行.文章对滨州学院在校学生的拇指类型、食环指类型、通贯纹、卷舌、耳垂五对性状进行了抽样调查,研究分析其遗传方式. 相似文献
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MIXED LINEAR MODEL APPROACHES FOR ANALYZING GENETIC MODELS OF COMPLEX QUANTITATIVE TRAITS 总被引：2，自引：0，他引：2
ＩＮＴＲＯＤＵＣＴＩＯＮＭａｎｙｇｅｎｅｔｉｃｍｏｄｅｌｓｂａｓｅｄｏｎｔｈｅａｐｐｒｏａｃｈｏｆＡＮＯＶＡ (ａｎａｌｙｓｉｓｏｆｖａｒｉａｎｃｅ)ｗｅｒｅｄｅｖｅｌ ｏｐｅｄｂｙＦｉｓｈｅｒ(1 92 5) .Ｓｏｍｅｏｆｔｈｅｓｅｍｏｄｅｌｓ,ｅ.ｇ .ＮＣｄｅｓｉｇｎＩａｎｄＩＩ(Ｃｏｍｓｔｏｃｋｅｔａｌ.,1 952 ;Ｈａｌｌａｕｅｒｅｔａｌ.,1 981 ) ,ｄｉａｌｌｅｌｍｏｄｅｌｓ(Ｙａｔｅｓ,1 94 7;Ｇｒｉｆｆｉｎｇ,1 956;ＧａｒｄｎｅｒａｎｄＥ ｂｅｒｈａｒｔ,1 966) ,ａｒｅｓｔｉｌｌｗｉｄｅｌｙｕｓｅｄｂｙｐｌａ… 相似文献
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Zhu Jun 《浙江大学学报(A卷英文版)》2000,1(1):78-90
New approaches based on general mixed linear models were presented for analyzing complex quantitative traits in animal models,
seed models and QTL (quantitative trait locus) mapping models. Variances and covariances can be appropriately estimated by
MINQUE (minimum norm quadratic unbiased estimation) approaches. Random genetic effects can be predicted without bias by LUP
(linear unbiased prediction) or AUP (adjusted unbiased prediction) methods. Mixed-model based composite interval mapping (MCIM)
methods are suitable for efficiently searching QTLs along the whole genome. Bayesian methods and Markov Chain Monte Carlo
(MCMC) methods can be applied in analyzing parameters of random effects as well as their variances.
Projects supported by NSFC (39670390, 39893350) and the NIH Grant GM32518 相似文献
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Rao CG Seshagiri SV Ramesh C Ibrahim Basha K Nagaraju H Chandrashekaraiah 《Journal of Zhejiang University. Science. B》2006,7(3):215-220
In the present study, polyvoltine germplasm stock ofAndhra Pradesh State Sericulture Research and Development, Institute （APSSRDI） was evaluated for its performance based on quantitative and qualitative traits. Twenty-one oval and 10 peanut cocoon shaped lines were reared in different seasons of the year. Since the polyvoltines are non-diapausing, six generations were reared and evaluated for various economically important traits based on evaluation index and sub-ordinate function statistical methods. Ten top ranked lines obtained by using both the methods were identified as potential parental strains. Among oval lines, APMI4, APMI 1, APMIS, APMW9, and APMI9, and among peanut lines APMD5, APMDI, APMD3, APMD9 and APMD8 were selected as base material. The identified high yielding lines will be used in various breeding programmes as initial parents for the synthesis of superior polyvoltine breeds/hybrids. 相似文献
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WOMBAT A tool for mixed model analyses in quantitative genetics by restricted maximum likelihood （REML） 总被引：31，自引：0，他引：31
Meyer K 《Journal of Zhejiang University. Science. B》2007,8(11):815-821
WOMBAT is a software package for quantitative genetic analyses of continuous traits, fitting a linear, mixed model; estimates of covariance components and the resulting genetic parameters are obtained by restricted maximum likelihood. A wide range of models, comprising numerous traits, multiple fixed and random effects, selected genetic covariance structures, random regression models and reduced rank estimation are accommodated. WOMBAT employs up-to-date numerical and computational methods. Together with the use of efficient compilers, this generates fast executable programs, suitable for large scale analyses. Use of WOMBAT is illustrated for a bivariate analysis. The package consists of the executable program, available for LINUX and WINDOWS environments, manual and a set of worked example, and can be downloaded free of charge from http://agbu. une.edu.au/~kmeyer/wombat.html 相似文献
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Effect of the scale of quantitative trait data on the representativeness of a cotton germplasm sub-core collection 总被引：1，自引：0，他引：1
Jian-cheng WANG Jin HU Ya-jing GUAN Yan-fang ZHU 《Journal of Zhejiang University. Science. B》2013,14(2):162-170
A cotton germplasm collection with data for 20 quantitative traits was used to investigate the effect of the scale of quantitative trait data on the representativeness of plant sub-core collections.The relationship between the representativeness of a sub-core collection and two influencing factors,the number of traits and the sampling percentage,was studied.A mixed linear model approach was used to eliminate environmental errors and predict genotypic values of accessions.Sub-core collections were constructed using a least distance stepwise sampling(LDSS) method combining standardized Euclidean distance and an unweighted pair-group method with arithmetic means(UPGMA) cluster method.The mean difference percentage(MD),variance difference percentage(VD),coincidence rate of range(CR),and variable rate of coefficient of variation(VR) served as evaluation parameters.Monte Carlo simulation was conducted to study the relationship among the number of traits,the sampling percentage,and the four evaluation parameters.The results showed that the representativeness of a sub-core collection was affected greatly by the number of traits and the sampling percentage,and that these two influencing factors were closely connected.Increasing the number of traits improved the representativeness of a sub-core collection when the data of genotypic values were used.The change in the genetic diversity of sub-core collections with different sampling percentages showed a linear tendency when the number of traits was small,and a logarithmic tendency when the number of traits was large.However,the change in the genetic diversity of sub-core collections with different numbers of traits always showed a strong logarithmic tendency when the sampling percentage was changing.A CR threshold method based on Monte Carlo simulation is proposed to determine the rational number of traits for a relevant sampling percentage of a sub-core collection. 相似文献
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Richard Lamb Leonard Annetta David Vallett Jonah Firestone Maureen Schmitter-Edgecombe Heather Walker 《The Journal of educational research》2018,111(4):446-458
Attention on P-20 science, technology, engineering, and mathematics (STEM) education has increased tremendously in recent years. Many efforts are underway to promote STEM major and career selection across the nation; specifically, in engineering and computer science. The authors' purpose was to examine an underlying profile combinations of latent traits that influence student STEM career selection while designing serious educational games (SEGs). The authors combine a number of quantitative analysis methods in an effort to develop a rich understanding of how a profile combination of traits interact with one another to effect selection of STEM careers and majors. Study participants were 585 students enrolled in a full-time traditional high school. The addition of SEG design experiences into the student profile increases the probability of STEM career selection by 5.1 times. 相似文献
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Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 总被引：5，自引：0，他引：5
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits （fruit length and fruit perimeter） in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage （1-12 d after flowering） for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage （13-60 datter flowering）. The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 相似文献
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Xie JK Kong XL Chen J Hu BL Wen P Zhuang JY Bao JS 《Journal of Zhejiang University. Science. B》2011,12(7):518-526
Rice straw is always regarded as a by-product of rice production, but it could be a significant energy source for ruminant
animals. Knowledge of the genetic variation and genetic architecture of cell wall traits will facilitate rice breeders by
improving relevant traits through selective breeding and genetic engineering. The common wild rice, Oryza rufipogon Griff., which is considered to be the progenitor of Oryza sativa, has been widely utilized for the identification of genes of agronomic importance for rice genetic improvement. In the present
study, the mapping of quantitative trait loci (QTLs) for acid detergent fiber (ADF), neutral detergent fiber (NDF), acid detergent
lignin (ADL), and ADL/NDF ratio was carried out in two environments using a backcrossed inbred line (BIL) population derived
from a cross between the recurrent parent Xieqingzao B (XB) and an accession of Dongxiang wild rice (DWR). The results indicated
that all four traits tested were continuously distributed among the BILs, but many BILs showed transgressive segregation.
A total of 16 QTLs were identified for the four traits, but no QTLs were in common in two environments, suggesting that environment
has dramatic effects on fiber and lignin syntheses. Compared to the QTL positions for grain yield-related traits, there were
no unfavorable correlations between grain yield components and cell wall traits in this population. The QTLs identified in
this study are useful for the development of dual-purpose rice varieties that are high in grain yield and are also high in
straw quality. 相似文献
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Raphael Falk 《Science & Education》2014,23(2):273-284
Life sciences became Biology, a formal scientific discipline, at the turn of the nineteenth century, when it adopted the methods of reductive physics and chemistry. Mendel’s hypothesis of inheritance of discrete factors further introduced a quantitative reductionist dimension into biology. In 1910 Johannsen differentiated between the phenotype, which defines traits, and their genotype, the hereditary essence of such traits and their entities—the genes. The efforts to characterize these entities culminated in 1953, in Watson–Crick’s physico-chemical double helix model of DNA, the hereditary matter. However, the more molecular biology advanced the less real were its entities: Genes became generic units of heredity. The increasing role of science in society, and the mutual interdependence of the two on each other augmented the urge of the public at large to find in science icons of authority; the generic nature of the gene concept allowed scientists to offer it as the bait, even though advances in research made it clear that a distinction must be maintained between advances in reductive methodologies and the progress of systems’ conceptions. Genes out of context are meaningless. There are no “genes for” a trait: even if a specific change in a site on the DNA sequence may end in a conspicuous change in a trait, it must be realized that many sites in the DNA, in the cell, and in the organism as a complex integrated system in its environment, determine or rather, condition traits. The role of science is asking questions by putting up hypotheses and suggesting methods of testing them rather than in providing definite answers. 相似文献