Chromosome numbers in Bolboschoenus (Cyperaceae) correspond to main morphotypes at a worldwide scale
摘要
Great progress in cytotaxonomic research during the last decades indicated an importance of relationships between morphological features, geographical distribution of plants, and chromosome counts. This study is aimed to fill the gaps in our knowledge on Bolboschoenus chromosome numbers related to morphological differentiation of plants and their distribution worldwide. We counted gametophytic chromosome numbers in meiotic phase of plants, collected from localities worldwide during the period 1980–2013, and cultivated in an experimental garden in Průhonice. The chromosome numbers of seven species (Bolboschoenus affinis, B. caldwellii, B. grandispicus, B. medianus, B. novae-angliae, B. robustus and B. schmidii) were counted for the first time. All the studied Bolboschoenus taxa were divided into groups according to chromosome numbers, which were found to correspond to morphotypes formerly described. We have improved the taxonomic classification of some species. The relationship between chromosome counts and morphotypes appeared to be identical within some continents, and may indicate parallel evolution within the genus.