中文摘要：

主基因加多基因混合遗传模型是用于分析数量性状表型数据的统计分析方法, 该方法便于育种工作者利用杂种分离世代的数据对育种性状的遗传组成初步判断,制定相应的育种策略,也可用于校验QTL定位所揭示的数量性状的性状遗传组成。回交自交系（BIL）群体是永久性群体，可以进行有重复的比较试验，适用于受环境影响较大的复杂性状的遗传研究。本研究以BIL群体为对象构建了４对主基因、主基因加多基因分离分析方法的遗传模型，包括2类11个遗传模型。利用基于IECM （iterative expectation conditional maximization）算法的极大似然分析方法估算各个混合遗传模型中的分布参数，用AIC值和一组适合性测验结果选取最优模型，并从入选模型的分布参数通过最小二乘法估计遗传参数。由1个模拟的随机区组试验对模型进行验证，模拟群体中遗传参数的估计值与设定值之间具有很好的一致性。利用本文建立的模型重新分析大豆回交自交系群体（Essex×ZDD2315）及其亲本对胞囊线虫（Heterodera glycines Ichinohe） 1号生理小种的抗性数据后发现4对主基因模型优于原报道的3对主基因模型，说明本方法的有效性和正确性。

英文摘要：

The segregation analysis of major genes plus polygenes is a statistical method for genetic analysis of quantitative traits. The method is particularly valuable for plant breeders to use their data accumulated from segregation populations to estimate the genetic system of target traits, which is necessary for designing breeding strategies and also useful for validating the results of QTL mapping. The backcross inbred line （BIL） population is one of the permanent populations, which is suitable for genetic analysis of complex traits and can be used in replicated experiments. For BIL population, the analytical procedures of three and less major genes plus polygenes mixed inheritance models have been established. The objective of the present study was to establish the analytical procedures of segregation analysis for four major genes plus polygenes mixed inheritance models in BIL population. Eleven genetic models with four additive and （or） epistatic major genes including those without and with polygenes were established. The component distribution parameters were solved and estimated by using maximum likelihood method based on IECM （Iterative Expectation Conditional Maximization） algorithm. Among the possible models, the best one was chosen according to Akaike’s Information Criterion （AIC） and a set of tests for goodness of fit. Then the genetic parameters of the optimal model were estimated through the least square method. For demonstration of the established procedures, a simulated data set of a randomized block experiment with three replications was analyzed and the estimated genetic parameters showed a relatively high consistency with those fixed for the model. To validate the usefulness of the established genetic models, the data of resistance to race of Cyst Nematode （Heterodera glycines Ichinohe） in soybeans from a BIL population derived from Essex×ZDD2315 along with their P1 and P2 were analyzed. The results show that the four major genes genetic model is better than three major genes g