作物杂种后代基因型值和杂种优良的预测方法

本文提出了利用作物亲本和Ｆ１预测杂种后代基因型值和杂种优势的统计分析方法。该方法运用加性－显性遗传模型,分析双列杂交试验资料,用ＭＩＮＱＵＥ（１）法估算方差分量以及预测遗传效应值。由加性和显笥效应预测值可进一步预测Ｆ１,Ｆ２,ＢＣ１,ＢＣ２,等不同世代的基因型值,在预测Ｆ１群体平均优势和 群丛超亲优势的基础上,可以推导出其它各世代的杂种优势。提出了预测杂种后代保持超亲优热世代数的简单公式,根据杂交组合Ｆ１群体平均优势和双亲相对遗传差异,便可预测该组合能的生产上直接利用的世代数。以棉花六个品种完全双列杂交试验资料为例,分析了各组合Ｆ１和Ｆ２的 基因型值、超亲优势和保持５％超亲优势的世代数。     

三交组合农艺性状的遗传模型及杂种优势预测方法

本文根据广义遗传模型的建模原理,按照三交组合方式的交配设计,提出了分析作物三交组合数量性状的加性-显性-上位性模型(ADAA模型),给出了不同环境下各世代群体的遗传效应分量,介绍了相应的统计分析方法,并推导了根据基因型值进一步预测三交组合后代杂种优势的一般公式.     

作物品种间杂种优势遗传分析的新方法

本文提出了分析双列杂交试验资料的两个遗传模型。第一个模型包括加性、显性和母体效应;第二个模型只包括简单的加性和显性效应。还介绍了分析杂种优势、估算遗传方差分量以及预测遗传效应值的相应统计分析方法。用所介绍的遗传模型和分析方法以及常用的Griffing配合力分析方法,分析了棉花6个品种双列杂交的产量性状,并进一步比较了不同方法的分析结果。采用本文所介绍的遗传模型和分析方法,可以克服用Griffing的配合力模型及其方法分析杂种优势和配合力遗传表现所存在的局限性。     

基因型值多次聚类法构建作物种质资源核心库

采用合适的遗传模型无偏预测基因型值,用基因型值进行聚类分析,采用马氏距离计算遗传材料间的遗传距离,并用不加权类平均法（ＵＰＧＭＡ）进行聚类,根据树型图,从遗传变异相似的每组二个遗传材料中随机选取一个遗传材料,如组内只有一个遗传材料,则选取该遗传材料,对所取的所有遗传材料再次聚类、取样,直至所取遗传材料的数量为总遗传的２０％￣３０％,这些遗传材料作迷为核心聚类。用方差同质性测验、均值ｔ测验评核心资源     

应用分子标记差异性预测作物杂种优势的研究进展

应用分子标记差异性预测作物杂种优势的研究进展李春丽①（中国水稻研究所生物工程系,杭州３１０００６）ＴｈｅＰｒｏｇｒｅｓｓｉｎＰｒｅｄｉｃｔｉｏｎｏｆＰｌａｎｔＨｅｔｅｒｏｓｉｓＵｓｉｎｇＭｏｌｅｃｕｌａｒＭａｒｋｅｒＬｉＣｈｕｎｌｉ②（Ｄｅｐａｒｔｍ...     

数量性状的基因型值计算

提出了在数量遗传中基因具有固定的量值—基因值的假设;假设认为基因值由基因的分子结构所决定而与所在的杂交组合无关．由此推导出以双亲的基因值向量为变量,数量性状的基因型值为结果的新的数量遗传模型．并给出了具体的计算方法和应用举例．     

二棱大麦熟期性状的遗传研究

以甘木二条等7个二棱大麦品种进行不完全双列杂交,对其亲本、F1和F2的抽穗期,灌浆期和成熟期三个性状以1992和1995年（播种年份）的两年资料,采用加性-显性-上位性（ADAA）模型进行遗传分析．遗传方差分量的比率估算表明,三个性状都存在上位性作用．除灌浆期外,其余二性状还受显性和加性效应的作用,并以加性为主．显性效应和加性效应与环境的互作均达显著水平,基因效应的预测值表明采用P3（黔浙1号）和P4（浙农大3号）较易获得早熟后代．     

综合性状及其分量的多元条件分析

提出基于混合线性模型的多元条件分析方法,用于分析复杂综合性状的分量对其目标性状的贡献。定义了贡献率和贡献遗传效应两个概念,贡献率测定给定分量性状的遗传变异对目标性状的贡献比率,贡献遗传效应衡量给定分量性状的遗传效应对目标性状的贡献值。运用所提出的新方法分析了棉花籽棉产量的3个分量对产量的贡献。     

小麦亲本间遗传距离预测杂种优势可行性的研究

本文通过10个小麦品种和按双列杂交配制的45个组合为材料,研究亲本间遗传距离预测杂种优势的可行性。结果表明：93.02％的样本实测值落在预测区间。     

加性-显性-母体效应及GE互作效应遗传模型的模拟比较

运用蒙特卡罗方法比较了8个亲本正反应的加性－显性－母体效应的全模型及缩减模型,当σ^2M和σ^2ME存在时,检测各项遗传方差分量的功效高达97％以上,如何存在σ^2M和σ^2ME而缩减模型未包括这两项效应时,除显性效应以外的各项方差分量都被高估。对于加性－显性模型,如果忽略了基因型与环境互作,σ^2ε和σ^2A将被高估。当母体效应和基因型与环境互作被忽略时,将显著地增加遗传效应预测值的方差。     

Models to estimate maternally controlled genetic variation in quantitative seed characters

Summary Estimating quantitative contributions to specific traits can be accomplished from a variety of genetic models (Mather 1949; Mather and Jinks 1971; Falconer 1981). Residual genetic effects, those beyond main and interaction effects of the embryo genotype, are often pooled under a single classification, termed maternal effects. Maternal contributions to seed-related traits can originate from various maternal sources (e.g., endosperm, testa and cytoplasm). Quantitative contributions of a maternal nature are not predictable from parental performance and effects are largely non-persistent over generations (Jinks et al. 1972). The methods used to determine maternal effects in quantitative traits often do not measure quantitative genetic parameters, while those that do are either complex or partially resolve potential contributions of individual sources of maternal effects. We present simple genetic models for estimating quantitative genetic parameters which take into account maternal effects expressed in the major seed tissues of higher plants.     

二棱大麦茎杆特性的ADAA模型的遗传研究

以二棱大麦(Hordeum,distichum L.)甘木二条等7个品种进行半双列杂交,对1992年和1997年的亲本、F     

Mean, genetic variance, and usefulness of selfing progenies from intra- and inter-pool crosses in faba beans (Vicia faba L.) and their prediction from parental parameters

 Determining the genetic potential of a base population from the properties of their parental lines would improve the efficiency of a breeding program. In the present study, we investigated whether the means of the parents and the genetic distance determined from RAPD data (GD) or multivariate analysis (Mahalanobis D²), mid-parent heterosis (MPH), and the absolute difference between means of the parents (∣P₁−P₂∣) can be used for predicting the means and genetic variances (σ^² _g ) of F_3:4 lines derived from different crosses in faba beans. The material comprised 18 intra- and 18 inter-pool crosses among lines from the Minor, Major, and Mediterranean germplasm pools. Fifty F_3:4 lines from each cross were evaluated for days to anthesis, plant height, seeds per plant, and seed yield in German (GE) and Mediterranean (ME) environments. GD estimates between parent lines ranged from 0.38 to 0.58, while D² ranged from 45.5 to 134.7. Correlations between means of the parents and F_3:4 lines were highly significant for most traits. Estimates of σ² _g for all traits showed non-significant correlations with MPH, GD, D². In one ME, ∣P₁−P₂∣ had significant associations with σ^² _g for seed yield and days to anthesis. The predicted usefulness of crosses, defined as the sum of the population mean and selection responses, was most closely associated with the means of F_3:4 lines. We conclude from this study that the means of F_3:4 lines can be predicted from the means of the parents, whereas the prediction of genetic variance is still an unsolved problem Received: 12 December 1997 / Accepted: 13 July 1998     

Relative family performance and variance structure of open-pollinated Douglas-fir seedlings grown in three competitive environments

Summary Open-pollinated Douglas-fir (Pseudotsuga menziesii var menziesii (Mirb.) Franco) families were tested in three contrasting competitive environments to test the hypothesis that relative performance as measured by total seedling dry weight is dependent upon distance or genotype of neighbors. The three competitive environmnts included (1) a mixture of individuals from all families planted at close spacing, (2) single (pure) family blocks planted at close spacing, and (3) individuals from all families planted at a wide, non-competitive spacing. Despite occasional large changes in rank between competitive environments and only moderate correlations of family means between competitive environments, the family x competitive environment interaction was non-significant. Furthermore, families did not differ significantly in competitive ability or density tolerance. The competitive environment in which seedlings were grown, however, had a large effect on estimates of variance components, which in turn led to large differences in estimates of heritability and genetic gain. Evaluation of families in mixture resulted in the largest estimates of heritability, while evaluation in pure family blocks resulted in the lowest. Analysis of correlated response to selection indicated that testing and selection in mixture result in the largest estimated gain, even if progeny of selected individuals are subsequently grown in a pure or non-competitive environment.Paper No. 2659 of the Forest Research Laboratory, Oregon State University