西葫芦熟性性状主基因-多基因遗传分析

以西葫芦自交系配制q-1×23-4G（组合1）和q-1×A-7（组合2）杂交组合，构建6个联合世代（P1、P2、F1、BC1、BC2和F2）群体，应用植物数量性状主基因-多基因混合遗传模型对西葫芦熟性性状进行遗传分析。结果表明：2个组合的第1雌花节位为D-2模型，始花期性状遗传为加性-显性-上位性两对主基因（B-1）遗传模型；2个组合的第1雌花节位均以主基因的加性效应为主，而始花期以加性效应和加性×显性上位性互作效应为主，组合1以第2对主基因加性效应为主；由于环境因素对西葫芦F2第1雌花节位和始花期有较大的影响，因此对第1雌花节位的选育定向选择会有较好的效果，在育种中对始花期性状的选择宜在高世代进行。

Analysis on Major Gene and Polygene Inheritance of Maturity Traits in Summer Squash

Six generations（P1, P2, F1, BC1, BC2 and F2）derived from 2 crosses q-1×23-4G（cross 1）and q-1×A-7（cross 2）were used to investigate inheritance of the 1st node female flower and early flowering date in the summer squash（Cucurbita pepo L.）by using major gene and polygene mixed inheritance model. The results showed that the 1st node female flower was controlled by D-2 model and the early flowering date was controlled by B-1 model. Genetic effects of the 1st node female flower of 2 crosses were mainly additive effect of major gene. But additive effect and additive × dominant epitasis effect mainly played role on early flowering date of 2 crosses. Early flowering date of cross 1 was mainly controlled by additive effect of the second major gene. Heritability values of environmental effect were relatively higher on the 1st node female flower and the early flowering date. These results indicated that directional selection should be effective on the 1st node female flower, but selection for early flowering date characteristics should be carried out on high separated generations.