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Start Over Creator Suda, Jan

12. Sorbus milensis, a new hybridogenous species from northwestern Bohemia

Creator:
Lepší, Martin, Vít, Petr, Lepší, Petr, Boublík, Karel, and Suda, Jan
Type:
article and TEXT
Subject:
apoximis, Czech Republic, endemic, hybridization, karyology, multivariate morphometrics, phytosociology, Rosaceae, SSR markers, Sorbus latifolia agg., and taxonomy
Language:
English
Description:
A new apomictic triploid (2n = 3x = 51) species belonging to the Sorbus latifolia group, S. milensis M. Lepší, K. Boublík, P. Lepší et P. Vít, putatively of hybridogenous origin between sexual Sorbus aria s.l. and S. torminalis, is described from the České středohoří Mts (northwestern Bohemia, Czech Republic). Several biosystematic techniques, including molecular (nuclear microsatellite markers), karyological (chromosome counts, genome size) and multivariate morphometrics were used to assess the variation in this species and justify its independent taxonomic status. The only known population of S. milensis consists of 38 adult and 19 juvenile individuals, is phenotypically homogenous and distinct from other Bohemian hybridogenous Sorbus species. All sampled individuals were karyologically uniform and showed little genetic variation. Sorbus milensis is a stenoendemic occurring on Milá hill (situated ca 9.5 km NNW of the town of Louny) where it grows on basaltic rocks, in ravines and on screes. The majority of the individuals grow in scree forests of the Tilio-Acerion alliance; other vegetation types include xeric scrub of the Prunion spinosae alliance and xerothermophilous grassland communities of the Festucion valesiacae alliance. A detailed distribution map for this species is provided as well as photographs of the type specimen.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

13. use of flow cytometry in the biosystematics, ecology and population bilogy of homoploid plants

Creator:
Loureiro, João, Trávníček, Pavel, Rauchová, Jana, Urfus, Tomáš, Vít, Petr, Štech, Milan, Castro, Sílvia, and Suda, Jan
Type:
article and TEXT
Subject:
biosystematics, ecology, flow sytometrry, genome size, homoploid species, hybridization, nuclear DNA content, population biology, and taxonomy
Language:
English
Description:
Over the last decade there has been a tremendous increase in the use of flow cytometry (FCM) in studies on the biosystematics, ecology and population biology of vascular plants. Most studies, however, address questions related to differences in genome copy number, while the value of FCM for studying homoploid plant groups has long been underestimated. This review summarizes recent advances in taxonomic and ecological research on homoploid plants that were made using FCM. A fairly constant amount of nuclear DNA within each evolutionary entity together with the often large differences between species means that genome size is a useful character for taxonomic decision-making. Regardless of the number of chromosomes, genome size can be used to delimit taxa at various taxonomic levels, resolve complex low-level taxonomies, assess the frequency of interspecific hybridization or infer evolutionary relationships in homoploid plant groups. In plant ecology and evolutionary biology, variation in genome size has been used for prediction purposes because genome size is associated with several phenotypic, physiological and/or ecological characteristics. It is likely that in the future the use ofFCM in studies on taxonomy, ecology and population biology of homoploid plants will increase both in scope and frequency. Flow cytometry alone, but especially in combination with other molecular and phenotypic approaches, promises advances in our understanding of the functional significance of variation in genome size in homoploid plants.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

14. Zvonek jemný - přehlížená vzácnost naší květeny

Creator:
Rauchová, Jana and Suda, Jan
Type:
article and TEXT
Language:
Czech
Description:
Okruh zvonku okrouhlolistého (Campanula rotundifolia) zahrnuje několik blízce příbuzných a fenotypově podobných taxonů, které často mají omezenou oblast výskytu. Jeden z opomíjených taxonů české flóry je subendemit zvonek jemný (C. gentilis). Znakem, který jej morfologicky odlišuje od ostatních taxonů, je přítomnost drobných papil na semeníku. Druh je karyologicky variabilní a zahrnuje dva cytotypy (diploidní a tetraploidní). Tento vzácný zvonek se v současnosti vyskytuje na 35 lokalitách ve středních, severních a severozápadních Čechách a na třech místech v Bavorsku. Bohužel počet jeho lokalit stejně jako počet jedinců klesá v důsledku změn ve vegetaci. and The aggregate species Campanula rotundifolia (Harebell) includes several closely related and phenotypically similar taxa which often show a restricted range of distribution. One of the largely neglected taxa of Czech flora is the subendemic species C. gentilis. Its distinct morphological feature is the presence of short papillae on the calyx tube. The species is karyologically polymorphic and encompasses both diploid and tetraploid cytotypes. This rare bluebell has recently been recorded in 35 localities in Central, North and North-West Bohemia and in three localities in Bavaria. However, the number of localities as well as the total number of individual plants have been declining due to changes in vegetation cover.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/