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0 2B is a duplication deficiency chromosome carrying a duplicated part of chromosome 2D;
1 variety shows also a 1AL.1RS wheat-rye translocation
2 variety shows also a 1BL.1RS wheat-rye translocation
3 variety shows also a 4BS.4BL-5RL wheat-rye translocation
4 variety shows also a ?/2R wheat-rye translocation (60)
5 varietiy shows also a 5R(4A) wheat-rye substitution
6 segregation of chromosomes in a progeny of plants heterozygous for 5B-7B translocation is not random; there is strong selection against genotypes with non balanced chromosome constitution and the lines with translocation significantly prevails in the progeny (147:89), thus, translocated 5B-7B chromosomes are capable of preferential transmission through the pollen; although there is cytogenetic evidences of recombination between normal and translocated chromosomes, the prevalence of, on one hand, recital molecular makers alleles in DH lines containing normal 5B and 7B chromosomes, and, on the other hand, arche alleles in DH lines with translocated 5B-7B chromosomes, indicates that recombination between normal and translocated chromosomes in meiosis of hybrids heterozygous for translocation is significantly reduced
7 the absence of chromosome 7D in the wheat-Thinopyrum ponticum partial amphiploid BE-1 was detected in some studies by multicolor genomic in situ hybridization, sequential FISH (fluorescence in situ hybridization) using repetitive DNA probes, and SSR marker analysis. In the previous cytogenetic and SSR marker analyses were expanded to include 25 other SSR markers assigned to wheat chromosomes 7A and 7D to confirm the presence of a 7A.7D translocation and to specify its composition; an almost complete chromosome 7A and a short chromosome segment derived from the terminal region of 7DL were detected, confirming the presence of a terminal translocation involving the distal regions of 7AL and 7DL; in both cases the position of the translocation breakpoint was different from that of known deletion line; the identification of the 7AL.7DL translocation and its breakpoint position provides a new physical landmark for future physical mapping studies, opening up the possibility of more precise localization of genes or molecular markers within the terminal regions of 7DL and 7AL.
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