对14个玉米自交系及其双列杂交组合(未反交)进行了试验。以杂种产量的中亲优势值和自交系间的遗传距离为指标,对亲本进行了聚类分析。结果表明,利用中亲优势值可将参试自交系分为四个优势群,其聚类结果与自交系的亲缘关系和育种实践吻合;各优势群间具有较大的产量杂种优势,而在优势群内的自交群系间,生育日数、株高、产量等性状的配合力存在较大差异;自交系间的遗传距离与产量杂种优势无相关性,在进行种质聚类时应慎重使用。本文还提出了育种上利用优势群的途径和策略。 Fourteen maize inbred lines and their double crosses (non-crossed) were tested. The parents were analyzed by cluster analysis based on the heterosis value of heterosis and the genetic distance between inbred lines. The results showed that the inbred lines could be divided into four dominant groups by using the pro-dominant value. The clustering results were in good agreement with the breeding practices and inbred lines. The heterotic groups had greater yield heterosis, However, there was a great difference in the combining ability between the inbred lines within the dominant group, the days with fertility, the plant height, the yield and other traits. The genetic distance between inbred lines had no correlation with yield heterosis, Should be used with caution. This paper also put forward the ways and tactics of utilizing dominant groups in breeding.