Abstract
In Europe, two North American species, Solidago canadensis and S. gigantea hybridize with native S. virgaurea producing the hybrids: S. ×niederederi, a hybrid between S. canadensis and S. virgaurea, and S. ×snarskisii, a hybrid between S. gigantea and S. virgaurea. The morphological description of both hybrids has been well established in contrast to the data on chromosome numbers which were insufficiently recorded or missing. The diploids of S. ×niederederi have been recently reported from a few localities in Austria and Lithuania. In this study, we evidenced a triploid of S. ×snarskisii from one locality in Lithuania, as well as confirmed diploids in the progenies of S. ×niederederi collected in 23 new localities in Austria, Poland, Lithuania, and Latvia, based on chromosome counting.
References
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<a href="https://doi.org/10.3732/ajb.0800200">https://doi.org/10.3732/ajb.0800200</a>
James, C.M., Wurzell, B.S. & Stace, C.A. (2000) A new hybrid between a European and a Chinese species of Artemisia (Asteraceae). Watsonia 23: 139–147.
Ja?wa, M., J?drzejczak, E., Klichowska, E. & Pliszko, A. (2018) Predicting the potential distribution area of Solidago ×niederederi (Asteraceae). Turkish Journal of Botany 42: 51–56.
<a href="https://doi.org/10.3906/bot-1703-17">https://doi.org/10.3906/bot-1703-17</a>
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<a href="https://doi.org/10.1080/00087114.1978.10796755">https://doi.org/10.1080/00087114.1978.10796755</a>
Karpavi?ien?, B. & Radušien?, J. (2016) Morphological and anatomical characterization of Solidago ×niederederi and other sympatric Solidago species. Weed Science 64: 61–70.
<a href="https://doi.org/10.1614/WS-D-15-00066.1">https://doi.org/10.1614/WS-D-15-00066.1</a>
Khek, E. (1905) Floristisches aus Ober-Oesterreich. Allgemeine Botanische Zeitschrift für Systematik 11: 21–23.
Krahulcová, A., Krahulec, F. & Kirschner, J. (1996) Introgressive hybridization between a native and an introduced species: Viola lutea subsp. sudetica versus V. tricolor. Folia Geobotanica et Phytotaxonomica 31: 219–244.
<a href="https://doi.org/10.1007/BF02812066">https://doi.org/10.1007/BF02812066</a>
Leitch, I.J. & Bennett, M.D. (1997) Polyploidy in angiosperms. Trends in Plant Science 2 (12): 470–476.
<a href="https://doi.org/10.1016/S1360-1385(97)01154-0">https://doi.org/10.1016/S1360-1385(97)01154-0</a>
Linnaeus, C. (1753) Species Plantarum. Impensis Laurentii Salvii, Stockholm, 1200 pp.
López-Caamal, A. & Tovar-Sánchez, E. (2014) Genetic, morphological, and chemical patterns of plant hybridization. Revista Chilena de Historia Natural 87: e16.
<a href="https://doi.org/10.1186/s40693-014-0016-0">https://doi.org/10.1186/s40693-014-0016-0</a>
Marciniuk, P., Musia?, K., Joachimiak, A.J., Marciniuk, J., Oklejewicz, K. & Wolanin, M. (2012) Taraxacum zajacii (Asteraceae), a new species from Poland. Annales Botanici Fennici 49: 387–390.
<a href="https://doi.org/10.5735/085.049.0611">https://doi.org/10.5735/085.049.0611</a>
Marciniuk, J., Marciniuk P. & Musia?, K. (2018) Taraxacum mariae, a new species of T. section Palustria (Asteraceae) from Poland. Phytotaxa 376 (5): 207–213.
<a href="https://doi.org/10.11646/phytotaxa.376.5.3">https://doi.org/10.11646/phytotaxa.376.5.3</a>
Migda?ek, G., Kolczyk, J., Pliszko, A., Ko?ci?ska-Paj?k, M. & S?omka, A. (2014) Reduced pollen viability and achene development in Solidago ×niederederi Khek from Poland. Acta Societatis Botanicorum Poloniae 83: 251–255.
<a href="https://doi.org/10.5586/asbp.2014.025">https://doi.org/10.5586/asbp.2014.025</a>
Morton, J.K., Venn, J. & Semple, J.C. (2017) Chromosome number determination in Solidago (Asteraceae: Astereae). Rhodora 119(980): 341–348.
<a href="https://doi.org/10.3119/17-03">https://doi.org/10.3119/17-03</a>
Morton, J.K., Venn, J. & Semple, J.C. (2019) Chromosome number determinations in Solidago gigantea (Asteraceae: Astereae). Rhodora 121 (988): 347–352.
<a href="https://doi.org/10.3119/0035-4902-121.988.347">https://doi.org/10.3119/0035-4902-121.988.347</a>
Musia?, K. & Szel?g, Z. (2015) Chromosome numbers in Hieracium (Asteraceae) from Central and Southeastern Europe I. Acta Biologica Cracoviensia Series Botanica 57 (2): 115–120.
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