LOSS OF NUCLEOLAR-ORGANIZER REGIONS DURING POLYPLOID EVOLUTION IN SCILLA-AUTUMNALIS

Authors
VAUGHAN HE JAMILENA M REJON CR PARKER JS GARRIDORAMOS MA
Citation
He. Vaughan et al., LOSS OF NUCLEOLAR-ORGANIZER REGIONS DURING POLYPLOID EVOLUTION IN SCILLA-AUTUMNALIS, Heredity, 71, 1993, pp. 574-580
Citations number
27
Categorie Soggetti
Genetics & Heredity
Journal title
Heredity → ACNP
ISSN journal
0018067X
Volume
71
Year of publication
1993
Part
6
Pages
574 - 580
Database
ISI
SICI code
0018-067X(1993)71:<574:LONRDP>2.0.ZU;2-7
Abstract
The organization and behaviour of nucleolar-organizer regions (NOR) of Scilla autumnalis were studied in two diploid races, their allotetrap loid and autoallohexaploid derivatives and hybrids between them. The d iploids of genome constitution AA and (BB7)-B-7 each have a pair of nu cleolar-organizer chromosomes while the polyploids AAB(7)B(7) and AAB( 7)B(7)B(7)B(7) only carry visible organizers on the B-7 chromosomes. I n situ hybridization using ribosomal probe pTA71 was used to localize ribosomal cistrons. In polyploids the sites of hybridization are limit ed to the B-7-derived nucleolar-organizer chromosomes and ribosomal ci strons have thus been deleted from the A genome. A NOR-associated C-ba nd has also been deleted.