%0 Journal Article
%T Meiosis en mutantes desin¨¢pticos con restituci¨®n cromos¨®mica en Rhoeo spathacea (Commelinaceae)
%A Garc¨ªa-Vel¨¢zquez
%A Armando
%J Acta Agron¨®mica
%D 2008
%I Universidad Nacional de Colombia Sede Palmira
%X this study was carried out with collected material of rhoeo spathacea in the states of veracruz, chiapas, tabasco, yucatan, quintana roo and michoacan, mexico. all material exhibited a diploid chromosome number (2n =12) in mitosis. in meiosis, all individuals showedring and /or chains at metaphase i. exceptionally several desynaptic mutants resulted desynaptic - sdr (dissociation of paired chromosomes). therefore, in meiosis rhoeo did not exhibit synapsis in parallel-fashion instead the chromosomes are united in end-to-end (no chiasmata-) fashion. then, there are not bivalents, no chiasmata-achiasmata- as there are not four chromatids two of which resulted sister-chromatids. but in anaphase i, there is high regular 6:6 disyuction and observed as "rings or donuts". in which short arms are oriented to the center of those figures. from selfed a desynaptic- sdr (gava 1.1) mutant, a progeny of 123 individuals resulted: 90 diploid-ring forming, 1 acrotrisomic (2n=13) equally ring-forming reverts its "meiotic behavior", but 29 diplandrogynous tetraploids (2n=24) and 3 hypertetraploids (2n=25) resulted desynaptics. the cytological behaviour is due to the fact that rhoeo is a dikaryon: diploids-ring forming and the trisomic also and present subgenome a, but polyploids present subgenome b which includes a desynaptic gene in both sister chromatids as result of restitution at second division(2n).
%K no orthodox meiosis
%K no parallel pairing
%K telomere-to-telomere attachment.
%U http://www.scielo.org.co/scielo.php?script=sci_abstract&pid=S0120-28122008000300005&lng=en&nrm=iso&tlng=en