Abstract: Cytological irregularities was observed during meiosis in hybrid F1 of crossing common wheat "Chinese Spring" ph1b mutant with octoploid or hexaploid triticale. More univalents, heteromorphic bivalents and multivalents were observed in PMCⅠ, and lagging chromosomes, chromosomal fragments and micronuclei in anaphaseⅠ and telophaseⅠ. The disorder of chromosome synapsis resulted in homoeologue pairing and exchanging, leading to translocation and recombination between nonhomologous chromosomes.

Key words: Wheat, ph1b mutant, Triticale, Homoeologous chromosomes