Introduction
Species of the genus Tulipa L. (Liliaceae) have great economic,
horticultural, esthetical, ecological, conservational and taxonomic
importance (Veldkamp and Zonneveld, 2012). They are bulbous monocots,
characterized by a high variability of vegetative and floral characters
which were traditionally used to characterize species. Furthermore, the
vegetative and floral characters appear to be plastic (polythetic),
sometimes even within populations of a species (Christenhusz et al.,
2013; Zonneveld and de Groot, 2012). Because of that, the taxonomy of
this genus is considered to be difficult, despite the existence of a
large body of literature (Eker et al., 2014; Zonneveld, 2009; Zonneveld
and de Groot, 2012). Taking that into consideration, the classification
of Tulipa has been revised several times (Turktas et al., 2013).
The total number of Tulipa species still is not exactly defined
and ranges from 40-150 species according to various researchers (Eker et
al., 2014). In the World Checklist of Selected Plant Families(Govaerts, 2019), 516 names have been listed for Tulipa , but only
102 taxa have been accepted, while in the Plant List (“The Plant
List,” 2013) 499 names have been listed for Tulipa and 120 taxa
have been accepted. According to Christenhusz et al . (2013) only
76 species are accepted. The number of Tulipa species native to
the Balkan Peninsula is much less, varying from 15 (Hayek 1933) to 22
(Govaerts 2010). In Kosovo the genus Tulipa is represented by
eight taxa (six species and two subspecies), belonging to the two
subgenera Eriostemones and Tulipa, respectively. The
subgenus Eriostemones is represented by T. sylvestris ,
which is represented by two subspecies, Tulipa sylvestris subsp.australis (Link) Pamp (accepted subsp.) and Tulipa
sylvestris subsp. sylvestris only accepted by the World
Checklist of Selected Plant Families (Govaerts, 2019). In Kosovo the
subgenus Tulipa is represented by several species: Tulipa
gesneriana L., Sp. Pl.: 306 (1753) (Millaku et al., 2018) has a hybrid
origin derived from T. agenensis, T. armena, T. suaveolens and
others (Govaerts, 2019). Tulipa scardica Bornm. is distributed in
Southern Kosovo and Macedonia (Mayer and Micevski, 1970). In Kosovo, it
is present near the village Krivenik, close to the border of Macedonia.
It is synonymized asTulipa
gesneriana L. (“The Plant List,” 2013; Zonneveld, 2016), accepted as
a species by the World Checklist of Selected Plant Families(Govaerts, 2019), but not accepted by Flora Eurepea (Tutin et al. 1980).Tulipa serbica Tatic & Krivošej is distributed on serpentine
soil in the South of Serbia (community Knjaževac: Mt. Rogozna near Donja
Kamenica) and Northern Kosovo (Beli Laz hill, near Ibar river) (Tatić
and Krivošej, 1997). Tulipa kosovarica Kit Tan, Shuka & Krasniqi
is distributed in Kosovo, in the serpentine area of Mirusha region at
the foot of Mt. Kozniku, between Mrasori and Llapçevë villages (Shuka et
al. 2012), as well as in the localities Guriç, Llapushnik, Qafë – Prush
and Devë (Millaku et al., 2018). Tulipa luanica Millaku is
distributed on limestone substrate on Mt. Pashtriku which is located in
the district of Prizren, Southern Kosovo near the border with Albania
(Millaku and Elezaj, 2015). Tulipa albanica Kit Tan &
Shuka was the first time described as a new species from Albania (Kukësi
district: from Kolshi to Surroj village, on serpentine slopes) (Shuka et
al., 2010), but was recently found in the Kosovar village of Deva too
(Millaku et al., 2018). Tulipa scardica, T. serbica, T. albanica,
T. kosovarica and T. luanica belong to the T. scardicacomplex (Christenhusz et al., 2013) and share many similar morphological
features (Shuka et al., 2010; Shuka and Tan Kit, 2012; Tatić and
Krivošej, 1997). Because of their similarities, these species sometimes
have been synonymized, erroneously identified or misclassified.
To study the taxonomy and relationships of these species, mainly their
morphological characteristics and their geographical distribution has
been used. Additionally, karyological analyses for T. albanica,(Shuka et al., 2010) and T. luanica (Millaku and Elezaj, 2015),
as well as nuclear genome size (DNA 2C-values) for T. albanica,(Osmani, 2018; Shuka et al., 2010), T. scardica (Zonneveld,
2009), T. kosovarica and T. luanica (Osmani, 2018) have
been used. However, DNA content and cytogenetic analyses are not known
for all of the species present in Kosovo in order to provide information
about species relationships.
DNA barcoding is a techniques, which has emerged in the last decades as
powerful tool in plant systematics and became important as an
inexpensive and reliable technique for phylogenetic studies (Kress,
2017). Molecular phylogenetic analysis using sequences from nuclear
ribosomal DNA (nrDNA) and chloroplast DNA (cpDNA) was successfully used
for phylogenetic analysis of the genus Tulipa . Thus,Tulipa DNA sequences from the ITS region (Christenhusz et al.,
2013; Fay et al., 2006; Turktas et al., 2013; Yanagisawa et al., 2012)
and the trnL-trnF region (Peterson et al., 2008) were used for
phylogenetic analyses.
This work aimed to determine the phylogenetic relationships of
wild-growing Tulipa species of Kosovo, employing the plastidtrnL-trnF and nuclear ITS region. To the best of our knowledge,
up to now no studies addressing this DNA barcodes for the KosovarTulipa species were reported.