ISSN:
1432-2242
Keywords:
Key wordsAegilops
;
Allotetraploid
;
Diploidization
;
Pairing control
;
Synaptonemal complex
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Chromosome pairing behaviour of the allotetraploid Aegilops species sharing the D genome, Ae. crassa (DDMM), Ae. cylindrica (DDCC) and Ae. ventricosa (DDNN), was analyzed by electron microscopy in surface-spread prophase-I nuclei. Synaptonemal-complex analysis at zygotene and pachytene revealed that synapsis in the allotetraploids was mostly between homologous chromosomes, although a few multivalents were also formed. Only homologous bivalents were observed at metaphase-I. It is concluded that the mechanism controlling bivalent formation in these species acts mainly at zygotene by restricting pairing to homologous chromosomes, but also acts at pachytene by preventing chiasma formation in homoeologous associations. These observations are discussed in relation to mechanisms of diploidization of polyploid meiosis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001220050353
Permalink
