Cytogenetic characteristics of wheat lines with modified 1RS.1BL rye-wheat translocation

The higher frequency (almost 90%) of inheritance through pollen of heterozygous hybrids has been shown for the modified 1RS.1BL translocation compared with the 1BL telocentric, and, as a result, the segregations at the Gli-B1 and Glu-B1 loci strongly deviated from the expected values. The distance between the Glu-B1 locus and the centromere was 15.7-24.4 cM. Products of the 1RS(m).1BL translocation "misdivision" were observed at a frequency of 0.05%. Both the Pavon MA1 lines and the winter wheat line with the 1RS(m).1BL (al) translocation have shown a significant decrease in the level of homologous chromosome pairing, causing aneuploidy. These lines did not contain any reciprocal translocations with respect to the Kuyal'nik cultivar. A "hybrid desynapsis" has been observed in F-1 hybrids (Kuyal'nik x Pavon MA1) in contrast to analogous hybrids from a winter line by the 1RS(m).1BL (al) type. No single case of the 21(Closed) (II) formation has been observed among the studied 693 pollen mother cells (PMCs), which would have indicated the presence of pairing between the short arms of the 1RS(m).1BL translocations and the intact chromosome 1B.