Multigenic self incompatibility in hexaploid Chrysanthemum

Eleven garden chrysanthemum siblings obtained through two generations of single-plant selfpollination were selfed and crossed in a complete diallel. Outcrosses to unrelated individuals were performed to test for male and female fertility. Since eleven crossing patterns were found inthe diallel, at least three genes must be assumed. Our data suggest independent gene action with intragenic dominance. One inbred, 77-AM3-3, expressed a high level of pseudo-self-compatibility (PSC) by giving some very low cross seed sets along with high self seed set. This inbred also exhibited variable PSC from season to season.