Chromosome Pairing in a Nulli-5b Di-5d Wheat Haploid
نویسندگان
چکیده
منابع مشابه
Substitution of rye chromosome 5r for chromosome 5b of wheat and its effect on chromosome pairing.
HEXAPLOID wheat normally exhibits homologous pairing, forming only bivalents at meiosis. However, in the absence of chromosome 5B, homoeologous as well as homologous pairing occurs ( SEARS and OKAMOTO 1958; RILEY and CHAPMAN 1958; RILEY and KEMPANNA 1963). In 5Bdeficient hybrids between wheat and related genera, the level of chromosome pairing is increaesd (RILEY, CHAPMAN and KIMBER 1959). In w...
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Bread wheat is a hexaploid (AABBDD, 2n=6x=42) containing three related ancestral genomes, each having 7 chromosomes, giving 42 chromosomes in diploid cells. During meiosis true homologues are correctly associated in wild-type wheat, but a degree of association of related chromosomes (homoeologues) occurs in a mutant (ph1b). We show that the centromeres are associated in non-homologous pairs in ...
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Meiotic chromosome pairing in Triticum aestivum is controlled by genetic systems promoting and reducing pairing. The pairing of homoeologous chromosomes is prevented principally by the activity of a single locus (Ph) distally located on the long arm of chromosome 5B. In certain hybrids, supernumerary chromosomes (B chromosomes) from Aegilops species can compensate for the absence of chromosome ...
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In tetraploid rye with single-substitution wheat chromosomes - 1A, 2A, 5A, 6A, 7A, 3B, 5B, 7B - chromosome pairing was analysed at metaphase I in PMCs with the C-banding method. The frequency of univalents of chromosome 1A was considerably higher than that of the other four wheat chromosomes of genome A (6A, 5A, 7A and 2A). Among chromosomes of genome B, the lowest mean frequency of univalents ...
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ژورنال
عنوان ژورنال: Australian Journal of Biological Sciences
سال: 1968
ISSN: 0004-9417
DOI: 10.1071/bi9680161