A Cytogenetic Analysis of the Hybrid Secale Cereale L. x Secale Montanum Guss. and Its Progeny.

ITHIN the genus Secale L. hybrids between various perennial forms have all shown regular meiotic chromosome behavior as have hybrids between different annual strains belonging to S. cereale L. In all hybrids between S. cereale and perennial forms, however, a translocation figure has been observed a t metaphase I in the PMC’s. The maximum association is apparently a ring-of-six, but this is seldom observed, which probably accounts for the earlier reports (SCHIEMANN and NURNBERG-KRUGER 1952; PRICE 1955) of a chain-of-six as the maximum association. Observations on recurring diakinesis configurations in the hybrid S. cereale L. X S. montanum Guss. have permitted identification of each of the chromosomes within the translocation figure together with the determination of the relative size and position of the translocated segments. New homologies evident in the Fz segregants from this hybrid have made possible additional interpretations of the structural relationships of the two species.