Volum 48 Nr. 1 (2022): Acta Horti Botanici Bucurestiensis
Articles
-
Sem studies regarding micromorphology of fruit, seed coat and pollen in genus hesperis l. (Brassicaceae)
Rezumat
The paper presents the micromorphological characteristics (SEM investigations) of fruits, seed coats and pollen grains of genus Hesperis in Austria. The siliquae are usually terete, glabrous and rarely with simple trichomes (subsp. nivea), straight or slightly curved. The seeds can present apical wings or not. The testa is reticulate and two main types were recognize based on seed coat surface, reticulate and ocellate-papillate. The pollen is tricolpate and exine is reticulate. The study revealed that palynological, fruit and seed micromorphological characteristics are significant in the taxonomy of the genus. An original dichotomic key for Hesperis species in Austria (H. matronalis subsp. matronalis and subsp. nivea, H. sylvestris, H. tristis) based on micromorphological characteristics is provided. -
First record of amaranthus viridis after over 25 years
Rezumat
We report the presence of Amaranthus viridis after over 25 years from the last mention. The species is native to South America and in Europe is naturalized or casual. The way of introduction in Romania is unknown. We provide information about its morphological features, distribution, biology, ecology and invasiveness. -
Alien flora from Brăila county – Romania
Rezumat
This paper presents the list of alien plant species from Brăila County (Romania). The inventory is based on personal observations in the field in the last two years. The study has recorded 81 alien taxa who belong to 30 families, 36 of them beeing invasive. The Americas, Asia and the Mediterranean area are the main places of origin of the taxa of the inventory. -
Contributions to the identification of hotspots of invasion of alien plant species in Mureș county (Romania)
Rezumat
A priority for the states of the European Union is the identification of invasive and potentially invasive alien species, their main routes of entry and spread, and the impact they have on various types of habitats. The aim of this study was to contribute to the knowledge of hotspots (areas with a large number of invasive species) or those where their abundance-dominance is very high and produces a major impact on native vegetation. Through the research carried out on invasive and potentially invasive alien species in Mureș County, 1204 records made in 168 locations in Mureș County were analyzed and 31 species of invasive alien plants were identified, of which three species are of concern for the European Union, namely: Asclepias syriaca, Ailanthus altissima și Impatiens glandulifera. In the study area, the species with the highest presence are: Erigeron annuus subsp. anuus identified in 248 points, Xanthium orientale subsp. italicum (201 points), Robinia pseudoacacia (142 points), Solidago canadensis (83 points), Erigeron canadensis and Reynoutria japonica (each with 74 points), and Ambrosia artemisiifolia (67 points). In the observation points, up to 4-6 species of invasive plants grouped in the same type of habitat were found. These were generally habitats subject to strong anthropogenic impact, roadsides, fallows, abandoned lands, and agricultural crops. Each identified species was analyzed from the chorological point of view, the bioforms, the ways and the purpose of their introduction, and the phytogeographical elements. -
Contributions to the study of alien invasive species in Harghita county (Romania)
Rezumat
The paper presents the inventory and chorology of the invasive and potentially invasive alien species identified in Harghita County following the research carried out during 2019-2021. Following field research conducted in Harghita County, 47 species of invasive plants belonging to 23 families were identified. These include three species on the List of Invasive Alien Species of European Union concern: Ailanthus altissima, Asclepias syriaca, and Impatiens glandulifera. Although the presence of these species is particularly noticeable near human settlements and heavily ruderalized places, as a consequence of the abandonment of agricultural land, invasive species have been identified in various types of habitats, especially those of grasslands, meadows and wetlands near watercourses. In addition to the contribution to the distribution of the taxa identified in the perimeter of this county, aspects related to the impact exerted by each species on the coenotic structure of the habitats in the observation points are also presented. Due to the abundance with which these invasive species develop in certain regions, they lead to the depletion and even replacement of the native flora, causing disruptions to the state of conservation of natural habitats. -
Analysis of some families from Carl Studniczka's herbarium
Rezumat
In the C. Studniczka's herbarium we have found new herbarium folder which contain herbarium samples from families: Salicaceae, Pinaceae, Ephedraceae, Taxaceae and Cupressaceae. Most of the analysed herbal material (117 herbarium sheets, with 323 samples of herbal plants) in this part of the C. Studniczka's herbarium were collected in Europe (105 herbarium sheets). According to the labels, the majority of herborized material was collected in the area of Austria (26 herbarium sheets). Most herbarium sheets belong to Flora von Wien collection (9). In reference to the part of Studniczka's herbarium which has already been analysed, there is one botanist or collector which is mentioned for the first time: Brotherston. Also collections listed for the first time are: Ex. Herb. A. Brotherston, Kelso and Herbarium R. Fritβe in Rybnik. Most herbarium sheets were collected by Studniczka himself (36). The oldest herbarium sheets dates from 1856, where as the newest ones date from 1902. The exact year of collection is missing from 13 herbarium labels.
