Forty-nine morphological characters were scored or measured on 44 populations (376 individuals) o... more Forty-nine morphological characters were scored or measured on 44 populations (376 individuals) of Viola subsect. Viola from the West Carpathians and adjacent areas (Slovakia, Czech Republic, Austria and Hungary). The presence of six species, namely V. alba (represented by subsp. alba), V. ambigua, V. collina, V. hirta, V. odorata and V. suavis s.l. was revealed based on pollen fertility, cytological
Solidago ×niederederi Khek (1905: 22) is a hybrid between North-American S. canadensis Linnaeus (... more Solidago ×niederederi Khek (1905: 22) is a hybrid between North-American S. canadensis Linnaeus (1753: 878) and European native S. virgaurea Linnaeus (1753: 880). Solidago canadensis was introduced to Europe in the 17th century (Kowarik 2003). It has spread invasively throughout Europe since the second half of the 19th century (Weber 1998), reaching, besides sites disturbed by human activity, also (semi)natural biotopes, as forest edges, abandoned meadows and field margins which are often inhabited by native S. virgaurea. Their hybrid was discovered for the first time in nature by a local schoolmaster Franz Niedereder in the area of Vorderstoder village (Austria). Niedereder sent a plant material of the assumed hybrid to Eugen Johan Khek (born in 1861, Neuhaus/Jindřichov Hradec; died in 1927, Vienna), the pharmacist and botanist who lived in Vienna since 1889 (Anonymous 1916). Khek described the hybrid species under the name S. ×niederederi in honour of his discoverer (Khek 1905). The protologue indicates that the relevant communication between Niedereder and Khek was going on between July 1900 (when they met for the first time) and February 1905 (when the hybrid’s description was published). Before its description, Khek studied the hybrid for four years and he saw a herbarium material from Niedereder as well as a living material. In the protologue, no particular herbarium specimens or illustrations had been indicated or associated with S. ×niederederi (Khek 1905).
Human alteration of watercourses is global phenomenon that has had significant impacts on local e... more Human alteration of watercourses is global phenomenon that has had significant impacts on local ecosystems and the services they provide. Monitoring of abiotic and biotic changes is essential to mitigating long-lasting effects, and the 23-year dataset from the Gabčíkovo Waterworks provided a rare opportunity to assess the impact of groundwater regimes on vegetation. The main aim of this study was to describe the effect of the Gabčíkovo Waterworks on vegetation structure and species composition of the adjacent riparian floodplain forests over the past 23 years. The results are based on studies of three permanent monitoring plots (PMPs) located in the Danube inland delta – two outside (PMP 1 and 3) and one (PMP 2) fully under the influence of the artificial supply system. Our results demonstrate that the Danube inland delta was negatively affected by the Gabčíkovo construction, particularly for sites outside of the artificial supply system. There was a significant decrease in soil moi...
ABSTRACT Five cytotypes have been reported for Jacobaea vulgaris (syn.: Senecio jacobaea); three ... more ABSTRACT Five cytotypes have been reported for Jacobaea vulgaris (syn.: Senecio jacobaea); three of them with euploid (tetraploid, hexaploid, and octoploid; 2n = 40, 60, and 80) and one with aneuploid (2n = 32) chromosome numbers. Among them, only tetra- and octoploid cytotypes are regularly found, the other two are very rare. In this study we re-evaluated the origin and systematic position of J. vulgaris octoploids. DNA ploidy levels, morphological, and genetic (AFLP, amplified fragment length polymorphism) data were generated for 38 populations of J. vulgaris from Central and Eastern Europe, and adjacent parts of North-Western Europe. Genetic dataset was upplemented with 16 populations of five closely related species: J. alpina, J. aquatica, J. erratica, J. erucifolia, and J. subalpina. The octoploid cytotype of J. vulgaris, known thus far only from Pannonia and Ukrainian Podillya regions, has also been found on two Baltic islands, O¨ land and Gotland. AFLP analyses showed clear genetic differences between tetra- and octoploid cytotypes and revealed that all octoploid plants are most likely of autopolyploid origin. The AFLP data also indicate that octoploids form two separate allopatric and monophyletic lineages, one represented by Pannonian and O¨ land populations, and the other represented by the populations from Podillya and Gotland. The octoploids from Gotland correspond to the previously recognized subspecies J. vulgaris subsp. gotlandica. The octoploids distributed in Pannonia are described here as a new subspecies, J. vulgaris subsp. pannonica.
Forty-nine morphological characters were scored or measured on 44 populations (376 individuals) o... more Forty-nine morphological characters were scored or measured on 44 populations (376 individuals) of Viola subsect. Viola from the West Carpathians and adjacent areas (Slovakia, Czech Republic, Austria and Hungary). The presence of six species, namely V. alba (represented by subsp. alba), V. ambigua, V. collina, V. hirta, V. odorata and V. suavis s.l. was revealed based on pollen fertility, cytological
Solidago ×niederederi Khek (1905: 22) is a hybrid between North-American S. canadensis Linnaeus (... more Solidago ×niederederi Khek (1905: 22) is a hybrid between North-American S. canadensis Linnaeus (1753: 878) and European native S. virgaurea Linnaeus (1753: 880). Solidago canadensis was introduced to Europe in the 17th century (Kowarik 2003). It has spread invasively throughout Europe since the second half of the 19th century (Weber 1998), reaching, besides sites disturbed by human activity, also (semi)natural biotopes, as forest edges, abandoned meadows and field margins which are often inhabited by native S. virgaurea. Their hybrid was discovered for the first time in nature by a local schoolmaster Franz Niedereder in the area of Vorderstoder village (Austria). Niedereder sent a plant material of the assumed hybrid to Eugen Johan Khek (born in 1861, Neuhaus/Jindřichov Hradec; died in 1927, Vienna), the pharmacist and botanist who lived in Vienna since 1889 (Anonymous 1916). Khek described the hybrid species under the name S. ×niederederi in honour of his discoverer (Khek 1905). The protologue indicates that the relevant communication between Niedereder and Khek was going on between July 1900 (when they met for the first time) and February 1905 (when the hybrid’s description was published). Before its description, Khek studied the hybrid for four years and he saw a herbarium material from Niedereder as well as a living material. In the protologue, no particular herbarium specimens or illustrations had been indicated or associated with S. ×niederederi (Khek 1905).
Human alteration of watercourses is global phenomenon that has had significant impacts on local e... more Human alteration of watercourses is global phenomenon that has had significant impacts on local ecosystems and the services they provide. Monitoring of abiotic and biotic changes is essential to mitigating long-lasting effects, and the 23-year dataset from the Gabčíkovo Waterworks provided a rare opportunity to assess the impact of groundwater regimes on vegetation. The main aim of this study was to describe the effect of the Gabčíkovo Waterworks on vegetation structure and species composition of the adjacent riparian floodplain forests over the past 23 years. The results are based on studies of three permanent monitoring plots (PMPs) located in the Danube inland delta – two outside (PMP 1 and 3) and one (PMP 2) fully under the influence of the artificial supply system. Our results demonstrate that the Danube inland delta was negatively affected by the Gabčíkovo construction, particularly for sites outside of the artificial supply system. There was a significant decrease in soil moi...
ABSTRACT Five cytotypes have been reported for Jacobaea vulgaris (syn.: Senecio jacobaea); three ... more ABSTRACT Five cytotypes have been reported for Jacobaea vulgaris (syn.: Senecio jacobaea); three of them with euploid (tetraploid, hexaploid, and octoploid; 2n = 40, 60, and 80) and one with aneuploid (2n = 32) chromosome numbers. Among them, only tetra- and octoploid cytotypes are regularly found, the other two are very rare. In this study we re-evaluated the origin and systematic position of J. vulgaris octoploids. DNA ploidy levels, morphological, and genetic (AFLP, amplified fragment length polymorphism) data were generated for 38 populations of J. vulgaris from Central and Eastern Europe, and adjacent parts of North-Western Europe. Genetic dataset was upplemented with 16 populations of five closely related species: J. alpina, J. aquatica, J. erratica, J. erucifolia, and J. subalpina. The octoploid cytotype of J. vulgaris, known thus far only from Pannonia and Ukrainian Podillya regions, has also been found on two Baltic islands, O¨ land and Gotland. AFLP analyses showed clear genetic differences between tetra- and octoploid cytotypes and revealed that all octoploid plants are most likely of autopolyploid origin. The AFLP data also indicate that octoploids form two separate allopatric and monophyletic lineages, one represented by Pannonian and O¨ land populations, and the other represented by the populations from Podillya and Gotland. The octoploids from Gotland correspond to the previously recognized subspecies J. vulgaris subsp. gotlandica. The octoploids distributed in Pannonia are described here as a new subspecies, J. vulgaris subsp. pannonica.
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