玉米雄穗分枝性状的数量遗传分析

Quantitative Genetic Analysis of Tassel Branch Number Traits in Maize(Zea mays L.)

以2个株型不同的玉米自交系自330和PH4CV构成的6世代群体为材料,目测计数玉米不同群体雄穗分枝数量。通过P1、P2、F1、F2、B1和B2共6个世代联合分析法,以玉米雄穗分枝数为性状,研究控制玉米雄穗分枝性状的基因遗传分离规律。结果表明:该性状在F2分离世代群体呈双峰分布,B1和B2群体分离世代呈多峰分布,说明玉米雄穗分枝性状遗传为多基因数量性状控制,且符合加性-显性-上位性多基因遗传模型(即C模型)。显性效应起主要作用,多基因遗传力较高,在74.83%～80.42%之间,若选择雄穗分枝较少的自交系必须从基础材料入手。这一研究结果为玉米雄穗分枝选择提供方法和理论依据。

Six generations of different plant type maize inbred lines Zi330 and PH4CV were used in the study,the tassel branch number was counted by eyeballing.P1,P2,F1,F2,B1 and B2 were used to study the inheritance of maize tassel branch number with joint analysis of multiple generations.The results were as follows： maize tassel branch number trait presented a two peak distribution in the F2 population,and a multi-peak distribution in the B1 and B2 populations,indicating that the trait was quantitative in nature and controlled by polygene.The inheritance of maize tassel branch number trait fitted the model of additive-dominance-epitasis polygene（C Model）.The dominance played the leading role.The polygene heritability was higher between 74.83% and 80.42%.If less tassel branch number inbred line was choosen basic materials must be started.The effects of polygene heritability were important on maize tassel branch number inheritance,and should be paid more attention in maize breeding.