Chromosome studies in New Zealand species of Brachyscome (Asteraceae)

Abstract Chromosome numbers were determined for plants of five species and seven additional entities of uncertain taxonomic status of Brachyscome . We confirmed the chromosome numbers of several species but found new numbers in plants related to B. humilis , B. montana and B. radicata . Karyotype analysis showed a common karyotype in the diploids and suggested that the polyploids are autopolyploids. There is some evidence of aneuploidy in plants related to B. sinclairii and B. radicata. Karyotype analysis suggests that structural chromosome changes may have accompanied polyploidy in tetraploid B. humilis.