Abstract: A double hap loid (DH ) population and six generations ( P1、P2、F1、B1、B2 and F2 )derived from a broccoli combination of 86101 and 90196 were used to investigate the inheritance of head2leaf trait in the B rassica oleracea L. var. italica Planch by usingmixed major gene p lus polygene inheritance model. The results showed that the head-leaf trait was controlled by linked two additive-additive additive-epitasis major genes plus polygene (E-220 model) in DH population and by two additive-dominant-epitasismajor genes plus additive-dominant-epitasis polygene ( E model) in the joint analysis of the six generations, and the major gene heritability were 70.80% , 73.59%, 57.70% and 87.07% in the DH, B₁ , B₂ and F₂ populations, respectively. The above results showed that the head-leaf traitwas controlled by two major genes plus polygene, and the major gene heritability was relatively high.

Key words: broccoli, head-leaf, major gene plus polygene, genetic analysis