Chromosome pairing with the synaptonemal complex in allohexaploid wheat, Triticum aestivum cv. Chinese Spring, has been investigated by serial section series through seventeen pollen mother cell nucleic at the zygotene stage using improved fixation and staining techniques. Homologous chromosomes are not aligned prior to synapsis and exchange of pairing partners and interlocking of chromosomes and bivalents occur at early zygotene. Chromosome knots, the distribution of centromeres and the change in chromatin condensation throughout zygotene are described with particular emphasis on their possible relationship to the resolution of interlockings and multivalents in accordance with the two-phase pairing pattern previously described in Bombyx and wheat.
- synaptonemal complex, interlocking, multivalent, centromere, telomere, prealignment, allopolyploidy, chromatin, zygotene, reconstruction