Abstract
1. Karyogenetical researches were carried out on trigeneric F1 hybrids raised from Triticum×Haynaldia F1 crossed with Secale.
2. Hybridization was successful to have trigeneric F1 in crossing Triticum× Haynaldia F1 with Secale, but it was failed in crossing Triticum×Secale F1 with Haynaldia.
3. The number of somatic chromosomes of the trigeneric F1 hybrids, T. dicoccum var. atratum×H. villosa F1×S. cereale (TdicHRF1), T. persicum×H. villosa F1×S. cereale (TperHRF1) and T. turgidum×H. villosa F1×S. cereale (TturHRF1), were 27 (TdicHRF1-1) 28 (TdicHRF1-2, TturHRF1-) and 29 (TperHRF1-2) respectively.
4. In two individuals of TdicHRF1 hybrid, the number of bivalents at heterotypic metaphase of PMCs is given in Table 3. Ring-shaped bivalents were occasionally observed besides stick-shaped ones (65.33% in No. 2 and 59.88% in No. 1). In both cases 3 of them seem to pair in autosyndesis of AB genome hromosomes of T. dicoccum. But it seems more probable that the bivalents of the two individuals may have been produced by conjugation of partial homologous chromosomes by translocation between the chromosomes of AB genomes or between the chromosomes of AB and R or V genomes. For in these individuals abundant ring-shaped bivalents were observed and also the number of bivalents was more numerous than expected, although the chromosomes were less than those of eu-tri-generic hybrid.
5. However the number of bivalents in heterotypic metaphase of PMCs TperHRF1 hybrid was at most 4. The bivalents may be due to autosyndesis of chromosomes of AB genomes of T. persicum. Ring-shaped bivalents, besides stickshaped, were rarely observed (6.06%).
