遗传效应

The results showed that:(1) we can mapping quantitative trait locus while estimating the variance component of QTL;(2) granddaughter design is better than daughter design when mapping QTL;(3) it is easy to map a QTL for trait with a high heriability and a large QTL variance contribution;(4) we can estimate the variance component of a QTL by TM-BLUP based on ML method whether the QTL has only 2 alleles or QTL has normal distributed alleles effects;(5) the estimation accuracy of variance component contributed by QTL was improved by using of grand daughter design;(6) the higher the heritability and the QTL variance contribution was, the more accurate estimation of QTL variance component.

结果表明：（1）采用随机QTL效应模型和最大似然法，在估计QTL方差组分的同时，能够定位QTL；（2）孙女设计与女儿设计相比，在其它因素相同时，容易检出QTL；（3）遗传力高，QTL方差贡献较大的性状，QTL检出的效果优于遗传力低，QTL方差贡献较小的性状；（4）无论QTL上有2个等位基因，还是QTL上等位基因的效应服从正态分布，都可将其看作随机效应，采用基于TM-BLUP的ML法，估计其方差组分和定位QTL；（5）QTL方差组分估计的准确性，孙女设计高于女儿设计；（6）遗传力高的性状，QTL方差贡献大的QTL，QTL方差组分估计的准确性高。

There are 2 alleles at a marker locus and they are codominant. We assumed that the sires used were heterozygous at all marker loci with known linkage phases and were mated to females which are randomly sampled from a population being in HardyWeinberg equilibrium.For further understanding of the values of treating QTL effect as random effect and the importance of estimating the variance component of QTL, we estimated the additive QTL effect under several factors combinations assuming that the QTL vanance component to be known.

为了进一步明确将QTL效应作为随机效应处理，并估计其方差组分的重要意义，本文在方差组分真值给定的前提下，采用随机QTL效应模型和单标记及侧翼标记信息，研究了不同试验设计、不同群体结构、不同QTL等位基因类型、不同遗传力和不同QTL方差贡献等因素组合下，TM-BLUP种畜遗传评定的效果。

The results showed the resistance was controlled by at least two pairs of genes, and was incompletely recessive. Effect of backcross was very significant and that of reciprocal cross was not. Resistance was dominated by nuclear genes, narrow inheritability was comparatively high. The resistance was in keeping with additive-dominance model, and dominance was dominating, and showed a quantitative character.

结果表明：苦瓜对白粉病的抗性受两对以上基因控制，两对主基因抗病相对感病为不完全隐性，回交效应极显著，正反交效应差异不显著，抗病性主要受核基因控制，两对主基因的狭义遗传力较高，符合加性－显性模型，加性效应较大，抗性效应在亲本和F1间存在极显著正相关，表现为数量性状遗传的特点。

In order to reduce calculation error, the frequency distribution of average values is used to compute the mixed distribution's digital features of each component distribution, thereinto, the number of the component distribution is determined by AIC, choose the number that meets the minimum value of AIC as the component number of mixed distribution, and the other parameters are estimated by EM algorithm; Secondly, because each component distribution is corresponding to a kind of major gene genotype, according to the values of the average and variance of the each component distribution, we can use the limit error of the normal distribution to plot each individual into the correspondent component distribution, namely into correspondent major gene genotype. Then we regard each major gene genotype as a treatment level of one-way analysis of variances, and the one-way multivariate analysis of variance is carried out to calculate the covariance matrix of major gene effect, covariance matrix of polygene effect, covariance matrix of environment effect and so on; At last, combining the weights of the each component distribution of mixed distribution, we can calculate the variance of major gene effect, the variance of polygene effect, environmental variance and the genetic gain of the quantitative trait.

为减小计算误差，本研究采用均值的频数分布来计算各成分分布的数字特征，其中成分分布个数根据AIC准则，选择使AIC值达到最小的成分分布个数作为混合分布的成分分布数，分布中其它参数的确定利用EM算法来估计；其次，每个成分分布对应一种主基因基因型，根据各个成分分布的均值和方差，利用正态分布的极限误差将每个个体划分到相应的成分分布中，即相应的主基因基因型中，将每种主基因型作为单因素方差分析的一个处理水平，对其进行单因素的多元方差分析，分别计算主基因效应协方差阵、多基因效应协方差阵、环境协方差阵等参数；最后结合混合分布中各成分分布的权重即各主基因基因型的分离比例，计算主基因效应方差，多基因效应方差和环境方差，以及遗传力等参数，进而计算该数量性状的遗传进展。

The major gene heritability and polygene heritability were 64.17% and 14.76% respectively, which showed major genes played major role in seed setting rate.

在主基因作用的效应中，加性效应和显性效应各占主基因效应的50％；主基因的遗传率较高，分别为56.97％和44.26％；多基因的遗传率很低，分别为1.24％和3.05％；环境对结实率的影响显著，其方差占总表型方差的43.07％和52.99％。

The relative efficiency of pre-selection of young bulls before progeny-testing with marker-assisted BLUP over conventional progeny-testing(i.e.random selection before progeny-testing)for five generations was studied using Monte Carlo simulation.

在主基因-多基因混合遗传模型的框架内模拟研究了种畜遗传评定的相对效率，比较了常规BLUP与标记辅助BLUP进行个体遗传评定的效果，模型中将与标记紧密连锁的QTL效应看作随机效应。

The unconditional and conditional analyses of genetic models and the corresponding statistic methods, including endospermic, cytoplasmic, and maternal plant genetic systems, were used to analyze the genetic relationships between protein content and the appearance quality traits of indica rice (Oryza sativa L.).

应用包括胚乳、细胞质和母体植株基因的遗传主效应以及基因型×环境互作效应的数量性状遗传模型及非条件和条件分析方法，研究了籼稻稻米蛋白质含量与外观品质性状间的遗传相关性，进一步揭示了籼稻糙米重、稻米直链淀粉含量对稻米蛋白质含量与外观品质性状间遗传相关性的影响。

Genetic models including genetic effects and genotype × environment intera ction effects for quantitative traits of triploid endosperms in cereal crops were used to analyze miling quality traits of indica rice in different environments.

采用包括遗传主效应和基因型与环境互作效应的种子三倍体遗传模型，分析了不同环境条件下籼稻稻米碾磨品质的遗传特性。

The result indicated that crude protein content was controlled by additive and no-additive effects, and crude fat, crude fiber and nitrogen-free extract were controlled by dominant effects, whereas crude ash was controlled additive and dominant effects.

结果表明，粗蛋白的遗传受加性、显性和上位性及环境效应控制，粗纤维、粗脂肪和无氮浸出物的遗传主要受显性效应控制，粗灰分的遗传受加性和显性效应共同控制。

A software for QTL mapping—QTLMapper 2. 0 written by C/C++ language was developed. The sotftware could analyze populations of DH, RIL, F〓 and permanent F〓, and could provide unbiased estimation for all genetic main effects and/or unbiased prediction for all QE interaction effects. The software could also predict heteroses of single-cross offspring based on QTL genetic main effects and/or QE interaction effects obtained in QTL analysis of F〓 or permanent F〓 population.

用C／C++语言编写了适于分析DH群体、RIL群体、F〓群体和永久F〓群体的QTL作图软件QTLMapper 2.0，能够提供对各项遗传主效应的无偏估计和／或对QE互作效应的无偏预测，还能基于F〓群体或永久F〓群体估计的QTL遗传主效应和／或QE互作效应预测单交后代杂种优势。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。