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The document provides an overview of the results of a preliminary guiding vote on proposals to amend the International Code of Nomenclature for algae, fungi, and plants. A total of 433 proposals were submitted to the XX International Botanical Congress in Madrid, Spain. The vote was conducted via email, and 201 completed ballots were received. The results of the vote for each proposal are presented in a table, indicating the number of "yes," "no," "edc" (refer to the Editorial Committee), and "spc" (refer to a Special-purpose Committee) votes. [Extracted from the article]

Recurrent polyploid formation and weak reproductive barriers between independent polyploid lineages generate intricate species complexes with high diversity and reticulate evolutionary history. Uncovering the evolutionary processes that formed their present-day cytotypic and genetic structure is a challenging task. We studied the species complex of Cardamine pratensis , composed of diploid endemics in the European Mediterranean and diploid-polyploid lineages more widely distributed across Europe, focusing on the poorly understood variation in Central Europe. To elucidate the evolution of Central European populations we analyzed ploidy level and genome size variation, genetic patterns inferred from microsatellite markers and target enrichment of low-copy nuclear genes (Hyb-Seq), and environmental niche differentiation. We observed almost continuous variation in chromosome numbers and genome size in C. pratensis s.str., which is caused by the co-occurrence of euploid and dysploid cytotypes, along with aneuploids, and is likely accompanied by inter-cytotype mating. We inferred that the polyploid cytotypes of C. pratensis s.str. are both of single and multiple, spatially and temporally recurrent origins. The tetraploid Cardamine majovskyi evolved at least twice in different regions by autopolyploidy from diploid Cardamine matthioli. The extensive genome size and genetic variation of Cardamine rivularis reflects differentiation induced by the geographic isolation of disjunct populations, establishment of triploids of different origins, and hybridization with sympatric C. matthioli. Geographically structured genetic lineages identified in the species under study, which are also ecologically divergent, are interpreted as descendants from different source populations in multiple glacial refugia. The postglacial range expansion was accompanied by substantial genetic admixture between the lineages of C. pratensis s.str., which is reflected by diffuse borders in their contact zones. In conclusion, we identified an interplay of diverse processes that have driven the evolution of the species studied, including allopatric and ecological divergence, hybridization, multiple polyploid origins, and genetic reshuffling caused by Pleistocene climate-induced range dynamics. [ABSTRACT FROM AUTHOR]

Database of published chromosome numbers and ploidy-level estimates of the tribe Alysseae is presented, together with the revised generic concept and the list of accepted names, to reflect the most recent taxonomic and phylogenetic studies in Alysseae. It is available on-line at . The tribe encompasses 24 genera and 277 species. Chromosome numbers and/or ploidy levels are known for 171 out of 297 recognized taxa. Of these, 95 (55.6 %) taxa are diploids, 43 (25.1 %) are polyploids, and 33 (19.3 %) involve both diploids and polyploids. The most common base chromosome number in the tribe is x = 8 and less frequent is x = 7. The highest variation in base chromosome numbers ( x = 7, 8, 11, 15) is found in the genus Hormathophylla. A key to all genera and descriptions of the two new genera Cuprella and Resetnikia are presented. Many new nomenclatural combinations, mainly in the re-established Odontarrhena (77), are proposed. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY: Contact zones between diploids and their autopolyploid descendants represent a unique evolutionary venue for studying polyploid establishment, cytotype coexistence, and interactions. Here, we examine cytotype coexistence in a diploid--tetraploid contact zone of a perennial herb, Cardamine amara, located north of the Alps by assessing cytotype spatial patterns, ecological divergence, and genetic variation and structure. METHODS: Flow cytometry was applied to screen DNA ploidy levels in 302 populations (3296 individuals) and the genetic variation of a selection of 25 populations was examined using microsatellite and AFLP markers. Environmental (landscape and climatic) data were analyzed to assess ecological differentiation between the cytotypes. KEY RESULTS: A parapatric distribution of the cytotypes with a relatively wide (over 100 km in some regions) secondary contact zone was identified. Mixed-ploidy populations, documented for the first time in this species, as well astriploid individuals were found along the diploid--tetraploid borderline. Different climatic requirements of the two main cytotypes were revealed, mirrored in their altitudinal separation. The tetraploids were genetically differentiated from both the diploids and the modeled, in silico autotetraploid genotypes, in accordance with the assumed polyploid origin and spread linked to past glaciations, and largely independent evolution in allopatry. CONCLUSIONS: The observed spatial and genetic patterns likely reflect the evolutionary and colonization history of the two cytotypes and have been maintained by multiple factors such as ecological divergence, limited gene flow between the cytotypes, and the restricted dispersal capacity. [ABSTRACT FROM AUTHOR]

Five cytotypes have been reported for Jacobaea vulgaris (syn.: Senecio jacobaea); three of them with euploid (tetraploid, hexaploid, and octoploid; 2 n = 40, 60, and 80) and one with aneuploid (2 n = 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 supplemented 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, Öland 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 Öland 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. [ABSTRACT FROM AUTHOR]