Basic chromosome number in Boronia (Rutaceae)—competing hypotheses examined
- 1 January 2006
- journal article
- research article
- Published by CSIRO Publishing in Australian Journal of Botany
- Vol. 54 (7), 681-689
- https://doi.org/10.1071/bt05050
Abstract
Rutaceae have attracted considerable attention because of the wide chromosome-number variation. Cytoevolution of the genus Boronia, with n = 7–36, has been controversial. The critical issue is whether the base chromosome number is x = 18 or x = 9 in this genus and in the family Rutaceae. Phylogenetic analysis based on random amplified polymorphic DNA (RAPD) markers was used to evaluate the hypothesis. Twenty decamer arbitrary primers were used to produce RAPD markers in 25 accessions of 18 Boronia species and a total of 559 DNA fragments was generated. UPGMA distance analysis and Wagner parsimony analysis on the DNA data produced two phylogenetic trees with very similar topology. The two trees generally supported the present classification of Boronia species. The exception was B. tenuis, which may be better treated as a new section or genus. Chromosome numbers of all the genotypes used in the analysis were counted with n = 7, 8, 9, 11, 16–36. Evolutionary distances between species were determined on the basis of branch length of the Wagner cladogram. Regression analysis indicated that Boronia chromosome number has a significant negative relationship with evolutionary distance. Chromosome number in Boronia evolved from higher to lower. The basic chromosome number for Boronia is suggested to be 18.Keywords
This publication has 28 references indexed in Scilit:
- Karyotype evolution in the genus Boronia (Rutaceae)Botanical Journal of the Linnean Society, 2003
- Cyto-evolution of Boronia genomes revealed by fluorescent in situ hybridization with rDNA probesGenome, 2003
- Meiotic chromosome behaviour and Boronia (Rutaceae) genome reorganisationAustralian Journal of Botany, 2003
- Cytoevolutionary patterns inRutaceaeÖsterreichische botanische Zeitschrift, 1993
- New chromosome numbers for rutaceaeAustralian Systematic Botany, 1992
- Chemosystematics of theRutaceae: Suggestions for a more natural taxonomy and evolutionary interpretation of the familyÖsterreichische botanische Zeitschrift, 1988
- A cladistic analysis of Boronia Sm. and Boronella baill. (Rutaceae)Australian Journal of Botany, 1984
- Periodicities in the Chromosome Numbers of the AngiospermsBotanical Gazette, 1982
- Biotic pollination mechanisms in the Australian flora — a reviewNew Zealand Journal of Botany, 1979
- Chromosome numbers in the Boronieae (Rutaceae) and their bearing on the evolutionary development of the tribe in the Australian floraAustralian Journal of Botany, 1954