Abstract
Chromosome morphology and number in 28 species of Sinosenecio, two of Tephroseris and one of Nemosenecio (Senecioneae-Asteraceae) from China were investigated. Sinosenecio is revealed to have four basic chromosome numbers: x = 13, 24, 29, and 30, with 24 and 30 being predominant and 13 and 29 each occurring in one species only. The incidence of polyploidy is low in the genus. The karyotypes are all rather symmetrical and generally quite uniform in the species of similar chromosome number in respect of chromosome constitution, albeit with some variation in chromosome size among species. The pattern of basic chromosome numbers is largely congruent with results of floral micromorphological and molecular phylogenetic studies, and strongly indicates that Sinosenecio as currently construed is a polyphyletic group, badly needing a taxonomic re-circumscription at the generic level. We propose that only those Sinosenecio species with x = 30 should be retained in the newly defined genus, whereas those with x = 24 (rarely 13) (except for S. newcombei and S. koreanus which may find a home in Tephroseris) may be described as a new genus or preferably transferred to the genus Nemosenecio, and that S. hainanensis, the only Sinosenecio species having x = 29 and a suite of unique morphological and palynological characters, should be described as a new monospecific genus, Hainanecio, possibly positioned in the subtribe Senecioninae. When Sinosenecio is re-circumscribed in this way, not only does the genus Sinosenecio itself tend to be monophyletic, but the subtribe Tephroseridinae, which is composed of Nemosenecio, Sinosenecio, and Tephroseris, also may consequently become a better characterized and thus more acceptable group.
Similar content being viewed by others
References
Arano H (1962) Cytological studies in subfamily Carduoideae (Compositae) of Japan VIII. The karyotype analysis in tribe Senecioneae. Bot Mag (Tokyo) 75:401–410
Arano H (1964) Cytological studies in subfamily Carduoideae (Compositae) of Japan XVI. The karyotype analysis in tribe Senecioneae. Bot Mag (Tokyo) 77:59–65
Arano H (1968) The karyotypes and the geographical distribution in some groups of subfamily Carduoideae (Compositae) of Japan. Kromosomo 72–73:2371–2388
Arano H (1970) The cytological studies in subfamily Carduoideae of Compositae of Japan. XXIII. The somatic chromosome number in fifty species, four subspecies and six varieties. J Saitama Univ Nat Sci 18:93–107
Arano H (1975) Cytogenetic studies in subfamily Carduoideae of Japanese Compositae XXVIII. The karyotypes and speciation in the Japanese Senecioneae. J Saitama Univ Nat Sci 24:15–29
Bremer K (1994) Asteraceae: cladistics and classification. Timber Press, Portland
Chang CC, Tseng YC (1974) Senecio. In: Anonymous (ed) Flora Hainanica 3. Science Press, Beijing, p 585
Chen YL (1988) Eight new species of the tribe Senecioneae (Compositae) from China. Acta Phytotaxon Sin 26:50–57
Chen YL (1995) The new species of the tribe Senecioneae (Compositae) from China. Acta Phytotaxon Sin 33:76–85
Chen YL (1999) Compositae-Senecioneae. In: Chen YL (ed) Flora Reipublicae Popularis Sinicae 77 (1). Science Press, Beijing, pp 1–358
Choudry SA, Tanaka R, Taniguchi K, Oginuma K (1980) Karyomorphology of Senecio nikoensis. Chromosome Inform Serv 29:8–10
Golden JL, Kim YD, Bain JF (2001) A re-evaluation of North American Tephroseris and Sinosenecio (Asteraceae: Senecioneae) based on molecular and micromorphological data. Canad J Bot 79:1195–1201
Ishikawa M (1916) A list of the number of chromosomes. Bot Mag (Tokyo) 30:404–448
Janovec JP, Barkley TM (1996) Sinosenecio newcombei (Asteraceae: Senecioneae): a new combination for a North American plant in an Asiatic genus. Novon 6:265–267
Jeffrey C (1992) The tribe Senecioneae (Compositae) in the Mascarene Islands with an annotated world check-list of the genera of the tribe. Notes on Compositae: VI. Kew Bull 47:49–109
Jeffrey C, Chen YL (1984) Taxonomic studies on the tribe Senecioneae (Compositae) of Eastern Asia. Kew Bull 39:205–446
Kochjarova J (1997) Náčrt taxonomickej problematiky rodu Tephroseris v Západných Karpatoch. Preslia 69:71–93
Koyama H (1965) On the chromosome number of Senecio nikoensis. Acta Phytotaxon Geobot 21:132
Koyama H (1966) Chromosome numbers on some species of Compositae. Acta Phytotaxon Geobot 22:80
Krahulcova A (1990) Selected chromosome counts of the Czechoslovak flora II. Folia Geobot Phytotaxon 25:381–388
Lee YN (1969) Chromosome number of flowering plants in Korea (2). J Kor Res Inst Bett Liv 2:141–145
Levan A, Fredga K, Sandberg AA (1964) Nomenclature for centromeric position on chromosomes. Hereditas 52:201–220
Liu JQ (1999) Systematics of the tribe Senecioneae subtribe Tussilagininae (Asteraceae) of the Eastern Asia. Dissertation, Institute of Botany, Chinese Academy of Sciences
Liu JQ (2000) A new species of Sinosenecio B. Nord. (Asteraceae, Senecioneae). Acta Phytotaxon Sin 38:192–194
Liu JQ (2004) Uniformity of karyotypes in Ligularia (Asteraceae: Senecioneae), a highly diversified genus of the eastern Qinghai-Tibet Plateau highlands and adjacent areas. Bot J Linn Soc 144:329–342
Liu Y, Yang QE (2010) Sinosenecio yilingii (Asteraceae), a new species from Sichuan, China. Bot Stud 51:269–275
Liu Y, Yang QE (2011) Hainanecio, a new genus of the Senecioneae, Asteraceae from China. Bot Stud 52 (1) (in press)
Liu Y, Chen GX, Yang QE (2009) Sinosenecio baojingensis (Asteraceae), a new species from Hunan, China. Bot Stud 50:107–113
Liu Y, Zhang DG, Yang QE (2010) Sinosenecio hupingshanensis (Asteraceae), a new species from Hunan and Hubei, China. Bot Stud 51:387–394
Löve Á, Löve D (1975) IOPB chromosome number reports XLVIII. Taxon 24:367–372
Lövkvist B, Hultgård UM (1999) Chromosome numbers in south Swedish vascular plants. Oper Bot 137:1–42
Murin A, Majovsky J (1978) IOPB chromosome number reports LXI. Taxon 27:375–392
Nordenstam B (1978) Taxonomic studies on the tribe Senecioneae (Compositae). Oper Bot 44:1–84
Nordenstam B (2007) Tribe Senecioneae. In: Kadereit JW, Jeffrey C (eds) The families and genera of vascular plants, vol 8. Springer, Berlin, pp 208–241
Nordenstam B, Pelser PB, Kadereit JW, Watson LE (2009) Senecioneae. In: Funk VA, Susanna A, Stuessy TF, Bayer RJ (eds) Systematics, evolution, and biogeography of Compositae. International Association for Plant Taxonomy, Vienna, pp 503–525
Pelser PB, Nordenstam B, Kadereit JW, Watson LE (2007) An ITS phylogeny of tribe Senecioneae (Asteraceae) and a new delimitation of Senecio L. Taxon 56:1077–1104
Robinson H, Carr GD, King RM, Powell AM (1997) Chromosome numbers in Compositae, XVII: Senecioneae III. Ann Missouri Bot Gard 84:893–906
Romero Zarco C (1986) A new method for estimating karyotype asymmetry. Taxon 35:526–530
Stebbins GL (1971) Chromosomal evolution in higher plants. Edward Arnold, London
Uhrikova A, Majovsky J (1980) IOPB chromosome number reports LXIX. Taxon 29:725–727
Wang LY, Pelser PB, Nordenstam B, Liu JQ (2009) Strong incongruence between the ITS phylogeny and generic delimitation in the Nemosenecio–Sinosenecio–Tephroseris assemblage. Bot Stud 51:435–442
Watanabe K, King RM, Yahara T, Ito M, Yokoyama J, Suzuki T, Crawford DJ (1995) Chromosome cytology and evolution in Eupatorieae (Asteraceae). Ann Missouri Bot Gard 82:581–592
Watanabe K, Short PS, Denda T, Suzuki Y, Ito M, Yahara T, Kosuge K (1999a) Chromosome numbers and karyotypes in the Australian Gnaphalieae and Plucheeae (Asteraceae). Austral Syst Bot 12:781–802
Watanabe K, Yahara T, Denda T, Kosuge K (1999b) Chromosomal evolution in the genus Brachyscome (Asteraceae, Astereae): statistical tests regarding correlations between changes in karyotype and habit using phylogenetic information. J Plant Res 112:145–161
Watanabe K, Yahara T, Hashimoto G, Nagatani Y, Soejima A, Kawahara T, Nakazawa M (2007) Chromosome numbers and karyotypes in Asteraceae. Ann Missouri Bot Gard 94:643–654
Zhang DG, Liu Y, Yang QE (2008) Sinosenecio jishouensis (Compositae), a new species from north-west Hunan, China. Bot Stud 49:287–294
Acknowledgments
We thank two anonymous reviewers for their invaluable comments on the manuscript, and Dr Qiong Yuan and Mr Tao Deng for their help during our field work. This work was supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-YW-415, KSCX2-YW-Z-0918) and National Natural Science Foundation of China (grant no. 30970183).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Liu, Y., Yang, QE. Cytology and its systematic implications in Sinosenecio (Senecioneae-Asteraceae) and two closely related genera. Plant Syst Evol 291, 7–24 (2011). https://doi.org/10.1007/s00606-010-0365-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00606-010-0365-3