Cytogenetic study of the genus Cousinia (Asteraceae, section Serratuloideae) in Iran

Masoud Sheidai,Kazem Mehdigholi,Ahmad Ghahreman,Farideh Attar

doi:10.1590/s1415-47572006000100022

Masoud Sheidai, Kazem Mehdigholi + Show 2 more

Open Access

https://doi.org/10.1590/s1415-47572006000100022

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Abstract

Meiotic studies of ploidy level, chromosome paring and chiasma frequency were performed on 11 Cousinia (Asteraceae) species of the section Serratuloideae. The diploid number of the species studied was 2n = 2x = 24 and 26 so these species possess two different basic numbers (x = 12 or 13), a phenomenon common to other sections of the genus. The chromosome numbers of 9 species are reported here for the first time. When the 2n = 24 and 2n = 26 species were subjected to cluster analysis based on relative meiotic characters two different clusters were formed indicating their distinctness. Our data support the results obtained from morphometry, anatomy, pollen morphology and molecular studies of the genus Cousinia.

Highlights

The genus Cousinia (Asteraceae) is of worldwide distribution and comprises approximately 672 species, of which about 235 occur in central, western, eastern and southeastern Iran
Cytological studies were performed on 11 Cousinia species (Table 1), vouchers specimens are being deposited in the Herbarium of Tehran University (HTU), Iran
In order to determine any significant difference in chiasma frequency and distribution among the species with either chromosome number (n) = 13 or n = 12 we performed analysis of variance (ANOVA) by the least significant differences (LSD) method (Sokal and Rolf, 1995; Sheidai et al, 2002)

Summary

Introduction

The genus Cousinia (Asteraceae) is of worldwide distribution and comprises approximately 672 species, of which about 235 occur in central, western, eastern and southeastern Iran. According to Boissier (1875) the Serratuloideae section contains 9 species while Rechinger (1970) in Flora Iranica considers 11 species for this section. Earlier reports on Iranian Cousinia are have been confined mainly to taxonomic studies (Ghahreman et al, 1999; Attar and Ghahreman, 2000; 2002) and a few chromosome number reports (Ghaffari and Djavadi, 1998; Ghaffari et al, 2000). Our study reported in this paper was the first cytological analysis of 11 Iranian species of the section Serratuloideae. We discuss the cytological changes which play a role in the species diversification of this section

Materials and Methods

Results and Discussion

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