The wild type is essentially homozygous. If the wild-type genotype is aa, the broad-leaved tree is dominant mutation, that is, its genotype is Aa (mutant), that is, dominant mutation occurs, and the mutants of the offspring hybridize, that is, character separation occurs.

If the wild-type genotype is aa, the mutant genotype is Aa, and the mutant genotype is AA, the offspring are all broad-leaved.

Multiple broad-leaved progeny selected for stem hybridization.