Abstract
Birches are generally known for their high genetic and morphological variability, which has resulted in the description of many species. Ojców birch was described in 1809 by Willibald Suibert Joseph Gottlieb Besser in Poland. Since then, several studies assessing its taxonomy were conducted. Today, various authors present Ojców birch at different taxonomic ranks. In Czechia, the Ojców birch is classified a critically endangered taxon and confirmed at one locality consisting of several tens of individuals. However, before a strategy for its conservation can be applied, we consider it necessary to assess the taxonomic position of the endangered Czech population and to evaluate its relationship to the original Polish population. This study aimed to evaluate the morphometric and genetic variability between populations of B. ×oycoviensis in Poland and the Czechia and their relationship to regional populations of B. pendula, one of the putative parental species of the Ojców birch. Altogether, 106 individuals were sampled, including the holotype of B. szaferi, the second putative parental species of B. ×oycoviensis, received from the herbarium of W. Szafer, which is deposited at the Institute of Botany in Kraków. Morphological analyses identified differences in leaves between B. ×oycoviensis and B. pendula. However, no significant differences were found in genome size between selected taxa/working units except for B. pendula sampled in Czechia. The identified difference of the Czech population of B. pendula is probably caused by population variability. Genetic variability between all the taxa under comparison, regardless of their origin, was also very low; only the benchmark taxa (B. nana and B. humilis) clearly differed from all samples analyzed. The results indicate minute morphological and negligible genetic variability between the Czech and Polish populations of B. ×oycoviensis. In light of our results, the classification of B. ×oycoviensis as B. pendula var. oycoviensis seems more accurate than all hitherto presented alternatives (e.g. B. ×oycoviensis as a separate species).
Highlights
The genus Betula is generally known for its extensive genetic and morphological variability among taxa [1, 2]
The specimens of B. ×oycoviensis were complemented by samples taken in the Botanical Garden of the Jagiellonian University (BGJU) in Krakow (Poland) and at Chomutov ZOO (Czechia; the sampled trees were transplanted from Volynein the past)
Significant differences between B. pendula and B. ×oycoviensis were identified in several leaf parameters by statistical analyses (Table 2)
Summary
The genus Betula is generally known for its extensive genetic and morphological variability among taxa [1, 2]. One intricate taxon of the genus Betula is the Ojcow birch (Betula ×oycoviensis Besser), which was first described by Besser [12] as B. oycoviensis. Ojcow birch is a diploid taxon (2n = 28) closely related to silver birch (B. pendula). The taxonomic position of the Ojcow birch and the character of its relationship to silver birch, remains unresolved. Several studies focused on determination its origin have been conducted [15,16,17,18] Based on this subsequent research, B. oycoviensis was classified as a hybrid between B. pendula and ‘Betula nova’ [15]. ×oycoviensis (as did, for example, Rutkowski [20]), some authors have recently classified this birch at lower taxonomic ranks, for example as B. pendula var. Throughout the following text, we refer to Oycow birch using the established scientific name B. ×oycoviensis (as did, for example, Rutkowski [20]), some authors have recently classified this birch at lower taxonomic ranks, for example as B. pendula var. oycoviensis [21]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
