Karyomorphological study of nine Tanacetum taxa (Asteraceae, Anthemideae) from Iran

Abstract

Chromosome number and morphology in nine taxa belonging to 10 populations of Tanacetum L. (Asteraceae) were investigated using karyological techniques. The chromosome number found in eight species was 2n = 18 (T. balsamita, T. budjnurdense, T. sonbolii, T. archibaldii, T. persicum, T. parthenium and T. canescens) while T. polycephalum subsp. duderanum and T. polycephalum subsp. azerbaidjanicum had 2n = 36. Six records are new while four records confirmed the previous data. At mitotic metaphase, all chromosomes had median point (M), median region (m), submedian (sm) or subterminal (st) centromeres. The karyotypes are classified in types 2A or 2B, showing the presence of a primitive symmetrical karyotype in the genus Tanacetum. An updated checklist of karyological data of the genus is also presented.

Keywords:

• chromosome number
• karyotype
• polyploidy
• Compositae
• Tanacetum

Acknowledgements

Financial support is acknowledged from the Research and Technology Council of Shahid Beheshti University. Appreciation is expressed to three anonymous referees with helpful comments.

The authors are thankful to Prof. Dr. Joan Vallès and Dr. Sonia Garcia from Barcelona University for their kind comments.

Appendix. List of chromosome numbers of Tanacetum taxa retrieved from published data.

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