Mechanisms of Transition of Chromosomes from a Mitosis to Meiosis and Prevention of Conjugation of Homoeolog at an Allohexaploidny Type of Wheat

The work presents the results of a cytology analysis of the nature of behavior of a univalent in anaphase I in a full series of monosomny lines of a grade of spring-sown soft field Milturum 553. On the basis of results of the research conducted and the available published data, it is established that the trigger of transition of chromosomes from a mitosis to meiosis are early spiraling of chromosomes and the subsequent co-orientation of centromeres in a zone of an initial pole of one haploid set of chromosomes. Prevention of conjugation of homoeologs is reached by spatial cultivation of chromosomes. In critical situations, there is a replacement of co-orientation of centromers in a zone of an initial pole of one homolog on another.