Search results for "Magnoliopsida"
showing 10 items of 60 documents
Typification of the Linnaean name Centaurea seridis (Asteraceae)
2014
The genus Centaurea Linnaeus (1753: 909) (Asteraceae) comprises a large number of taxa mainly occurring in the Mediterranean region and southwest Asia (Susanna & Garcia-Jacas 2007). Centaurea seridis Linnaeus (1753: 915) is distributed from south Europe (Spain incl. Balearic Islands, Italy incl. Sicily, France, Albania and Greece) to northwest Africa (Algeria, Morocco and Tunisia). From a nomenclatural standpoint, Centaurea seridis has not been typified (Jarvis 2007: 402). This paper proposes the designation of a lectotype for this Linnaean name, based on the analysis of the protologue and original material.
Ferula sommieriana (Apiaceae), a new species from Pelagie Islands (Sicily)
2021
Ferula sommieriana, a new species occurring in Lampedusa and Linosa, islands of Pelagie Archipelago in the Sicilian Channel, is described and illustrated. Previously it was attributed to F. communis, from which it differs in several features regarding mainly the morphology and anatomy of terminal leaf lobes and mericarps, as well as the shape and size of reproductive structures. Its ecology, conservation status and relationships with other allied Mediterranean species of the sect. Ferula are provided, as well as the analytical keys of the species belonging to the aforesaid section.
Nothodissotis (Melastomataceae), a new genus from Atlantic Central Africa, including the new species N. alenensis from Equatorial Guinea
2019
Based on morphological and phylogenetic evidence, a new genus of Melastomataceae (Melastomateae), Nothodissotis Veranso-Libalah & G.Kadereit, gen. nov., is described from Atlantic Central Africa. Nothodissotis is distinguished from other African Melastomateae genera by its calyx-lobes that are notched at apex and asymmetrical (vs. entire and symmetrical). Nothodissotis includes two species: the type species N.barteri (Hook.f.) Veranso-Libalah & G.Kadereit, comb. nov. (syn. Dissotisbarteri Hook.f.), and the new species N.alenensis Veranso-Libalah & O. Lachenaud, sp. nov., described and illustrated here. Both species are restricted to open vegetation on rock outcrops w…
Melastomeae come full circle: biogeographic reconstruction and molecular clock dating.
2001
Rhexia, with 11 species in the Coastal Plain province of North America, is the only temperate zone endemic of the tropical eudicot family Melastomataceae. It is a member of the only pantropical tribe of that family, Melastomeae. Based on the chloroplast gene ndhF, we use a fossil-calibrated molecular clock to address the question of the geographic origin and age of Rhexia. Sequences from 37 species in 21 genera representing the tribe's geographical range were analyzed together with five outgroups. To obtain better clade support, another chloroplast region, the rpl16 intron, was added for 24 of the species. Parsimony analysis of the combined data and maximum-likelihood analysis of ndhF alone…
Towards an ontogenetic understanding of inflorescence diversity
2013
Backgrounds and aims Conceptual and terminological conflicts in inflorescence morphology indicate a lack of understanding of the phenotypic diversity of inflorescences. In this study, an ontogeny-based inflorescence concept is presented considering different meristem types and developmental pathways. By going back to the ontogenetic origin, diversity is reduced to a limited number of types and terms. Methods Species from 105 genera in 52 angiosperm families are investigated to identify their specific reproductive meristems and developmental pathways. Based on these studies, long-term experience with inflorescences and literature research, a conceptual framework for the understanding of infl…
Testing the ontogenetic base for the transient model of inflorescence development
2013
† Backgrounds and Aims: Current research in plant science has concentrated on revealing ontogenetic processes of key attributes in plant evolution. One recently discussed model is the ‘transient model’ successful in explaining some types of inflorescence architectures based on two main principles: the decline of the so called ‘vegetativeness’ (veg) factor and the transient nature of apical meristems in developing inflorescences. This study examines whether both principles find a concrete ontogenetic correlate in inflorescence development. † Methods: To test the ontogenetic base of veg decline and the transient character of apical meristems the ontogeny of meristematic size in developing inf…
Cytotoxicity of 40 Egyptian plant extracts targeting mechanisms of drug-resistant cancer cells
2019
Abstract Background The multidrug resistance (MDR) phenotype encounters a major challenge to the success of established chemotherapy in cancer patients. We hypothesized that cytotoxic medicinal plants with novel phytochemicals can overcome MDR and kill MDR-cells with similar efficacy as drug sensitive cells. Purpose We evaluated plant extracts from an unexplored ecosystem in Egypt with unusual climate and nutrient conditions for their activity against sensitive and multidrug-resistant cancer cell lines. Material and methods/study design Methylene chloride: methanol (1:1) and methanol: H2O (7:3) extracts of 40 plants were prepared resulting in a sum of 76 fraction containing compounds with v…
Molecular cloning and functional bacterial expression of a plant glucosidase specifically involved in alkaloid biosynthesis.
2000
Monoterpenoid indole alkaloids are a vast and structurally complex group of plant secondary compounds. In contrast to other groups of plant products which produce many glycosides, indole alkaloids rarely occur as glucosides. Plants of Rauvolfia serpentina accumulate ajmaline as a major alkaloid, whereas cell suspension cultures of Rauvolfia mainly accumulate the glucoalkaloid raucaffricine at levels of 1.6 g/l. Cell cultures do contain a specific glucosidase. known as raucaffricine-O-beta-D-glucosidase (RG), which catalyzes the in vitro formation of vomilenine, a direct intermediate in ajmaline biosynthesis. Here, we describe the molecular cloning and functional expression of this enzyme in…
Orobanche australis Moris ex Bertol. the correct name for O. thapsoides Lojac. (Orobanchaceae)
2022
The taxonomic relationships between Orobanche australis and O. thapsoides are analyzed through the study of the original material. These species are also compared with other morphologically similar ones occurring in the Mediterranean (O. canescens, O. pubescens, O. palaestina, O. amethystea). The lectotype of O. palaestina is designated. From the comparison of these taxa it is evident that O. australis and O. thapsoides refer to the same taxon, to which the name O. australis must be given by priority. The distribution of this species includes Sardinia, Sicily, Peninsular Italy and Southern France. It grows on pastures from the sea level to about 1000 m of altitude, host of Asteraceae. An id…
New records of the genus Orobanche L. (Orobanchaceae) to the Tunisian flora with lectotypification of the name O. rapum-genistae Thuill.
2023
Based on several field surveys and on the study of original material, we have identified three new species of Orobanche L. s.s. (Orobanchaceae) new to the flora of Tunisia. Orobanche alba Willd., O. calendulae Pomel, and O. gracilis Sm. are reported as new for the country, and the occurrence of O. rapum-genistae Thuill. is confirmed. The lectotypification of O. rapum-genistae is here proposed with a specimen housed in Genève (G). The geographical distribution of the four taxa in Tunisia is given, and details of habitats and hosts are provided. Altogether, the genus Orobanche in Tunisia now includes 18 species; a dichotomous key is proposed to facilitate the identification of these taxa.