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FIGURE 2. A. Flower, side view. B. Flower, upper view. C. Perigon with stamens. D. Bud. E. Anther. F. Ovary. G. Stigma. H. Fruit. I in Charybdis glaucophylla (Asparagaceae), a new species from Sardinia
No full textFIGURE 2. A. Flower, side view. B. Flower, upper view. C. Perigon with stamens. D. Bud. E. Anther. F. Ovary. G. Stigma. H. Fruit. I. Seed. Illustration by Salvatore Brullo based on Bacchetta & Pontecorvo s.n. (CAT).Published as part of Bacchetta, Gianluigi, Brullo, Salvatore, D'Emerico, Saverio, Pontecorvo, Cristiano & Salmeri, Cristina, 2012, Charybdis glaucophylla (Asparagaceae), a new species from Sardinia, pp. 16-26 in Phytotaxa 69 (1) on page 20, DOI: 10.11646/phytotaxa.69.1.4, http://zenodo.org/record/506619
FIGURE 1 in Charybdis glaucophylla (Asparagaceae), a new species from Sardinia
No full textFIGURE 1. Diagnostic features of Charybdis glaucophylla. A. Habit. B. Inflorescence. C. Leaves. D. Inflorescence detail. E. Fruits. Illustration by Salvatore Brullo based on Bacchetta & Pontecorvo s.n. (CAT).Published as part of Bacchetta, Gianluigi, Brullo, Salvatore, D'Emerico, Saverio, Pontecorvo, Cristiano & Salmeri, Cristina, 2012, Charybdis glaucophylla (Asparagaceae), a new species from Sardinia, pp. 16-26 in Phytotaxa 69 (1) on page 19, DOI: 10.11646/phytotaxa.69.1.4, http://zenodo.org/record/506619
Indagini cariomorfometriche in tre taxa poliploidi del genere Arum
No full textIl presente contributo fornisce informazioni sulla cariomorfometria di tre specie del genere Aru
Comparative chromosome studies in species of subtribe Orchidinae (Orchidaceae)
Full text linkIn our study, FISH mapping using 18S-5.8S-25S rDNA and 5S rDNA sequences was performed for the first time on Ophrys tenthredinifera Willdenow, 1805, Serapias vomeracea (Burman f., 1770) Briquet, 1910 and Himantoglossum hircinum (Linnaeus, 1753) Sprengel, 1826. A detailed study was also performed on O. tenthredinifera using Giemsa-staining, silver-staining, CMA fluorescence banding and fluorescence in situ hybridisation (FISH) with rDNA probes. We analysed two subspecies, i.e. O. tenthredinifera subsp. neglecta (Parlatore, 1860) E.G. Camus, 1908 and O. tenthredinifera subsp. grandiflora (Tenore, 1819) Kreutz, 2004 by the traditional Feulgen method and constructed the karyotype. The cytotaxonomic im-plications for both taxa are also discussed. In Himantoglossum hircinum, FISH and silver staining high-lighted differences in the number of two rDNA families (35S and 5S) with respect to Barlia robertiana (Loiseleur-Deslongchamps, 1807) Greuter, 1967. In addition, fluorescence in situ hybridisation was also applied to diploid (2n = 2x = 36) and triploid (2n = 3x = 54) Anacamptis morio (Linnaeus, 1753) R.M. Bateman, Pridgeon et M.W. Chase, 1997. As far as we are aware, this is the first case of autotriploidy observed in A. morio
Polyploidy in Muscari neglectum (Asparagaceae) by analysis of karyotype and Giemsa C-banding patterns
No full textThis study provides new karyological information on polyploid cytotypes of Muscari neglectum. Classical cytogenetic with the Feulgen technique and banding with Giemsa was used. Pentaploid, hexaploid and heptaploid levels of ploidy are here reported. The complement of the rare heptaploid
cytotype consisted of 2n=7x=63: 49m+14sm chromosomes. Two heptaploid specimens with chromosome numbers 60 and 62 were also found. Karyotypes were symmetrical, with metacentric chromosomes more numerous than submetacentric. The morphometric parameters MCA and CVCL
were used for the evaluation of karyotype asymmetry. For the first time, a detailed study using Giemsa C-banding is reported. The C-banding patterns included centromeric and terminal bands. In the cytotype with 62 chromosomes, the banding patterns identified the presence of a chromosome with terminal band in both arms. To explain the origin of this karyotype, we suggest that fusion occurred between a group IV chromosome and a group V chromosome. The relationship between the polyploid cytotypes of M. neglectum is discussed
New Cytogenetic Data for the Neottieae Tribe (Orchidaceae) in the Mediterranean Region
Full text linkThis work presents a summary of cytogenetic data, including new information, on several species within the tribe Neottieae, with an update of the karyotype for 23 species belonging to the genera Cephalanthera, Limodorum, Epipactis, and Neottia (including Listera). Each of these four genera also presents distinctive chromosomal features, such as bimodal karyotypes. Our research includes insights into the distribution of constitutive heterochromatin, measured using C-banding and, in some cases, specific fluorochromes for the detection of A-T- and G-C-rich DNA. In the Epipactis group, it is noteworthy that when using the Giemsa banding technique, certain species (e.g., E. placentina, E. meridionalis) with a chromosome number of 2n = 38 were observed to exhibit a conspicuous wide band of constitutive heterochromatin on the long arm of the third pair in a subcentromeric position, resembling what has been observed in E. helleborine. These differences also have the potential to contribute to the diversification of these species. Based on the karyological results obtained, a hypothesis regarding the origin of certain species within the E. helleborine group is proposed. Additionally, karyological analyses conducted on a specimen of E. microphylla revealed chromosome counts ranging from 36 to 40. Somatic metaphases exhibited evident structural alterations in certain chromosomes, showing rearrangements probably caused by translocation phenomena. Based on the data obtained from the species within the studied genera, it is conceivable that variations in chromosomes, both structurally and in the distribution of constitutive heterochromatin, exert a significant influence on the evolution of the karyotype. Moreover, in many entities belonging to the Neottieae tribe, these processes may also contribute to the diversification of the phenotype in some instances
Karyotype’s Rearrangement in Some Hybrids of the Orchidinae Subtribe
Full text linkBased on our karyological findings in the Anacamptis Rich., Ophrys L., and Serapias L. genera, we have identified chromosomal markers within some hybrids and elucidated their interrelationships. Mitotic chromosomes of fifteen taxa were analyzed using the conventional Feulgen staining method. Only for Anacamptis ×gennarii (Rchb. f.) H.Kretzschmar, Eccarius & Dietr. [A. morio (L.) R.M.Bateman, Pridgeon & M.W.Chase × A. papilionacea (L.) R.M.Bateman, Pridgeon & M.W.Chase] and its parental species were some data obtained and reported with the banding method with Giemsa, Hoechst 33258 fluorochrome, and the FISH techniques. Our research involved new chromosomal measurements of fifteen taxa, including six hybrids, along with schematic representations. Morphometric parameters, i.e., MCA and CVCL, were used to evaluate karyotype asymmetry. Of meaning were the analyses performed on chromosomal complements of selected hybrids, which distinctly revealed marker chromosomes present in one or both putative parental species. Among the parents identified in some hybrids, Ophrys tenthredinifera Willd. has shown some interest due to the presence in its karyotype of a pair of chromosomes (n.1) showing a notable secondary constriction on the long arm. Indeed, one of the homologs is clearly distinguishable in the analyzed hybrids, where it clearly emerges as one of the putative parents. Given the challenges in detecting certain karyomorphological features within the Orchidinae subtribe using alternative methods, such as Giemsa C-banding or fluorescence banding, the Feulgen method remains valuable for cytogenetic characterization. It helps us to understand the genomes of hybrids and parental species, thus contributing to a deeper understanding of their genetic composition
Orchidaceae in Puglia (Italy): Consistency, Distribution, and Conservation
Full text linkA study of the distribution of orchid species in Puglia, based on an analysis of 2084 bibliographic reports from 2000 to 2022, was carried out with the aim of revising and updating the information on the consistency of the Orchidaceae family in Puglia, with a special focus on assessing threatened species occurring inside and outside protected areas. The work presents a checklist of the Orchidaceae taxa (genera, species, and subspecies) found in the region, including observations on genera and species that present taxonomic challenges. A total of 113 taxa (i.e., species and subspecies), distributed across 16 genera, are listed in alphabetical order. The most representative genera were Ophrys (51 taxa), Serapias (15 taxa), and Epipactis (11 taxa). Additionally, 49 taxa (43.4%) were found to be endemic to Italy, with 21 of these, mostly belonging to the Ophrys genus, being exclusive to Puglia. Our study notes two different trends of distribution: a predominantly coastal distribution for orchid records located in southern Puglia (the Salento peninsula) and a more widespread distribution for the other provinces. Our study also shows that the greatest number of records locate orchids in protected areas with a positive correlation between their presence and habitats cited in Directive 92/43/EEC
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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