ISSN:
1615-6110
Keywords:
Angiosperms
;
Caryophyllaceae
;
Petrorhagia prolifera
;
P. velutina
;
P. glumacea
;
P. nanteuilii
;
Chromosome numbers
;
karyotype
;
meiotic behaviour
;
polyploidy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Cytogenetic investigations have been made in the fourPetrorhagia species and hybrids of the sectionKohlrauschia. The three diploid species show close similarities in chromosome number, size and morphology, with the exception ofP. velutina, where one pair of metacentric chromosomes is represented by a pair of telocentrics. Meiotic studies in hybrids indicate close genomic homology between the diploid species and also between the two floral forms ofP. prolifera. The tetraploidP. nanteuilii behaves as an allotetraploid forming only bivalents at meiosis and results suggest thatP. velutina andP. prolifera are the diploid progenitors of this species. Since meiosis in diploid and triploid hybrids results in extensive intergenomic pairing it is concluded that the natural tetraploid has a bivalent promoting mechanism that prevents pairing between the genomes of its diploid progenitors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00989005
