Epicuticular Waxes Provide Insights into Phytochemical Differentiation of Natural Populations of Pinus mugo Turra sensu stricto.

Phytochemical diversity and differentiation of nine native populations of Pinus mugo sensu stricto from Julian Alps, Southern Carpathians and Balkan Peninsula were analyzed in regard to their epicuticular wax compounds. GC/MS and GC-FID analyses of the hexane extracts of needle samples, collected from 118 individuals of P. mugo, revealed the presence of six diterpenes, three primary alcohols and 10 n-alkanes ranging from C19 to C29 (except n-alkane C21 ). According to simple linear regression, the contents of epicuticular wax compounds showed generally weak correlations with tested bioclimatic, orographic and geographic parameters, leading to assumption about their genetic conditioning. The multivariate statistical analyses suggested the existence of two chemical entities: the Alpine and the South Carpathian, while the Balkan populations appeared heterogeneous as three of them belonged to the Alpine and one to the South Carpathian group. The obtained results are largely consistent to those previously published in reference to morpho-anatomical and molecular characters of P. mugo, supporting the hypothesis of colonization of Balkan Peninsula from two different glacial refugia: from the Alps (across the Dinarides) and from the Southern Carpathians. Extending this study to the entire range of P. mugo complex should provide a clearer picture of its phytochemical diversity and differentiation.

Essential Oil Composition of Centaurea atropurpurea and Centaurea orientalis Inflorescences from the Central Balkans - Ecological Significance and Taxonomic Implications.

The essential oil composition of Centaurea atropurpurea and Centaurea orientalis flowering heads (capitula) from Central Balkans have been determined by GC-FID and GC/MS analyses. In total, 121 compounds were identified, representing on average 97.7% of the oil composition. In all samples, sesquiterpenes were most abundant group, representing 53.9 - 74.0% of the total oil. Sesquiterpene hydrocarbons dominated in all studied populations of C. orientalis and C. atropurpurea, except C. atropurpurea f. flava in which essential oil was characterized with high level of oxygenated sesquiterpenes. The dominant components differed between species, and also between typical C. atropurpurea and C. atropurpurea f. flava. The most abundant compounds of essential oil of C. orientalis were germacrene D and α-cadinol. In C. atropuruprea, germacrene D and ß-caryophyllene were the most abundant, while caryophyllene oxide and ß-caryophyllene were dominant in C. atropurpurea f. flava oil. Taxonomical and ecological implications are further discussed.

Alien plant species distribution in Romania: a nationwide survey following the implementation of the EU Regulation on Invasive Alien Species.

Background: Biological invasions pose an increasing risk to nature, social security and the economy, being ranked amongst the top five threats to biodiversity. Managing alien and invasive species is a priority for the European Union, as outlined in the EU Biodiversity Strategy for 2030 and the Kunming-Montreal Global Biodiversity Framework. Alien plant species are acknowledged to impact the economy and biodiversity; thus, analysing the distribution of such species provides valuable inputs for the management and decision-making processes. The database presented in the current study is the first consolidated checklist of alien plant species that are present in Romania, both of European Union concern and of national interest. This database complements a prior published distribution, based only on records from literature, bringing new information regarding the occurrence of alien plants in Romania, as revealed by a nationwide field survey. We consider this database a valuable instrument for managing biological invasions at both national and regional levels, as it can be utilised in further research studies and in drafting management and action plans, assisting stakeholders in making informed decisions and implementing management actions. New information: We present the results of the first nationwide survey of alien plant species in Romania, conducted between 2019 and 2022, in the framework of a national project coordinated by the Ministry of Environment, Waters and Forests and the University of Bucharest. The present database complements and updates the database published by Sirbu et. al (2022), which included occurrence records published until 2019. The new database includes 98323 occurrence records for 396 alien plant species in 77 families, with most species belonging to the Asteraceae family. One alien plant species in our database, the black locust Robiniapseudoacacia L., had more than 10,000 occurrence records. The distribution database also includes information on newly-reported invasive alien plant species of European Union concern in Romania (i.e. the floating primrose-willow Ludwigiapeploides (Kunth) P.H.Raven) and documents the presence of plants in 44 additional families compared to Sirbu et al. (2022). Each entry includes information on species taxonomy, location, year, person who recorded and identified the alien plant, geographical coordinates and taxon rank.