Does Solidago litoralis (Asteraceae) merit specific rank? Insights from cytogenetic, molecular and ecological data

Solidago litoralis (Asteraceae) is a psammophile plant endemic to the northern coasts of Tuscany, Italy. During time, different authors have considered it either as a separate species, subspecies or variety of the European S. virgaurea, but few studies of experimental taxonomy have been investigating the relationship between these two taxa. Aim of this study is to compare S. litoralis and S. virgaurea from different points of view: cytogenetic (karyotype analysis, localization of rDNA loci and genome size estimation), molecular (using two plastidial molecular markers), and ecological (by comparing functional characters). A difference in ecological responses to habitats is confirmed, even though S. virgaurea is potentially capable of assuming ecological strategies similar to those of S. litoralis. Despite this, cytogenetic and molecular analyses failed to reveal any significant difference supporting a specific distinction of S. litoralis. The latter taxon is here hypothesized as being an ecotype at the initial steps of a speciation event, better recognized at subspecific level (S. virgaurea subsp. litoralis)

Epidemiological Transition and Strategies for the Control of Hepatitis A in Serbia

Background: Improvements in socioeconomic and hygienic conditions during the past decades led to declining hepatitis A (HA) seroprevalence in many countries. Aiming at informing HA vaccination policy, we assessed current epidemiological trends in Serbia by analyzing surveillance data for 2002–2021. Methods: Data on cases and outbreaks were obtained from the Serbian national surveillance database and descriptively analyzed. HA incidence was calculated in relation to time, patients’ residence, and demographics. Results: Overall, 13,679 HA cases and 419 outbreaks were recorded with the highest incidence in the southeast. Downward HA trends were observed, while infant mortality was halved, and gross domestic product based on purchasing power parity (GDP PP) per capita, tripled. The average incidence dropped from 14.8 (95% CI 14.4–15.2)/100,000) in 2002–2006 to 1 (95% CI 0.9–1.1)/100,000)/100,000 in 2017–2021, while the number of outbreaks decreased (from 174 to 14). Sporadic cases and family clusters living in poor sanitary conditions occurred in recent years. The contact route of transmission was dominant (410/419, 97.9%). The highest average age-specific HA incidence shifted from 5–9 years in 2002–2006 to 10–19 years in 2017–2021.Serbia is transitioning towards very low HA endemicity. Enhanced surveillance and vaccination of high-risk groups are recommended as future public health priorities. © 2023 by the authors

Genome size shifts: karyotype evolution in Crepis section Neglectoides (Asteraceae)

Plant genome size evolution is a very dynamic process: the ancestral genome of angiosperms was initially most likely small, which led to a tendency towards genome increase during evolution. However, findings in several angiosperm lineages demonstrate mechanisms that also led to genome size contraction. Recent molecular investigations on the Asteraceae genus Crepis suggest that several genomic reduction events have occurred during the evolution of the genus. This study focuses on the Mediterranean Crepis sect. Neglectoides, which includes three species with some of the smallest genomes within the whole genus. Crepis neglecta has the largest genome in sect. Neglectoides, approximately twice the size of the two species Crepis cretica and Crepis hellenica. Whereas C.cretica and C.hellencia are more closely related to each other than to C.neglecta the karyotypes of the latter species and C.cretica are similar, while that of C.hellenica differs considerably. Here, the karyotypic organisation of the three species is investigated with fluorescence in-situ hybridisation and studied in a molecular phylogenetic framework based on the nuclear markers Actin, CHR12, CPN60B, GPCR1 and XTH23. Our findings further corroborate the occurrence of genome size contraction in Crepis, and suggest that the difference in genome size between C.neglecta and C.cretica is mostly due to elimination of dispersed repetitive elements, whereas chromosomal reorganisation was involved in the karyotype formation of C.hellenica