ISSN:
1573-6849
Keywords:
computer-aided karyotyping
;
FISH
;
Giemsa banding
;
Helianthus
;
nucleolar organizing region
;
rDNA
;
5S rRNA genes
;
silver staining
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The karyotype of H. annuus was analysed by computer-aided image processing with respect to the chromosome length, arm ratio, occurrence and chromosomal position of intercalary heterochromatin and the location of 18S/25S and 5S ribosomal RNA genes. The karyotype was subdivided into a group of four acrocentric chromosome pairs, of which two were distinguishable by HKG (HCl, KOH, Giemsa) banding and a group of 13 meta- to submetacentric pairs. The latter could be subdivided into seven pairs with one and six pairs with two HKG bands. Three pairs of submetacentric satellite chromosomes revealed 18S/25S rDNA loci after fluorescence in situ hybridization (FISH) and silver staining . A fourth, smaller and possibly inactive, locus occurred in the terminal position on a metacentric pair. One submetacentric satellite chromosome pair revealed a 5S rRNA gene locus in the pericentromeric position; a second locus marked a submetacentric pair with one HKG band. The C-banding technique marks exclusively centromeric heterochromatin. Measurements of chromosomes in combination with Giemsa banding and FISH enabled the discrimination of most chromosome pairs of the sunflower.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018412912790
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