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1.
PhytoKeys ; 243: 215-230, 2024.
Article de Anglais | MEDLINE | ID: mdl-38974889

RÉSUMÉ

A new species of Eriotheca (Bombacoideae, Malvaceae) from montane wet forests in the Atlantic Forest of Bahia, northeastern Brazil, is described and illustrated. It is known from only three populations situated between 750 m and 850 m in elevation on mountain summits and categorized as Endangered (EN) based on IUCN criteria. Eriothecapaganuccii is distinct from all congeners by the combination of coriaceous to strongly coriaceous leaves and remarkable few-seeded, globose to subglobose woody capsules that contain scanty kapok and the largest seeds known in the genus to date. The affinities of E.paganuccii to morphologically similar species as well as the importance of obtaining phenologically complete collections are discussed.

2.
PhytoKeys ; 243: 31-45, 2024.
Article de Anglais | MEDLINE | ID: mdl-38938541

RÉSUMÉ

Linariabimaculata comb. et stat. nov., from the overlooked Central Algarve plant endemism centre, is here lectotypified and redescribed as a full species based on Linariaviscosavar.bimaculata, which was historically misidentified under allopatric L.spartea and L.viscosa. Traditional herbarium taxonomy and citizen science observations were combined to document the geographical range of the four species of Linariasubsect.Versicolores in the Algarve and amend an identification key for the Iberian clade of this subsection. Geographical patterns and morphological similarity suggest a sister relationship between L.bimaculata and L.algarviana, unveiling a new possible example of parallel speciation linked to a purple to yellow shift in corolla colour. Besides the yellow flowers, L.bimaculata differs from L.algarviana in the more elongate fertile stems and the invariably erect-patent corolla tube. It is assessed as Vulnerable (VU) according to the IUCN Categories and Criteria.

3.
PhytoKeys ; 239: 1-12, 2024.
Article de Anglais | MEDLINE | ID: mdl-38463655

RÉSUMÉ

The paper provides an identification key and an annotated list of all six species of the genus Ridsdalea J.T.Pereira & K.M.Wong (Rubiaceae, Gardenieae) recorded in the flora of Vietnam, along with data on their valid names, synonyms, types, and distribution. A new species, R.backanensis, discovered in the limestone area of Bac Kan Province (northern Vietnam), is described and illustrated. Detailed data on its characters, ecology, distribution, phenology, preliminary IUCN conservation status, and taxonomical notes are given. The newly discovered species is potentially interesting for cultivation as an ornamental tree that may be effectively used in garden and urban green architecture.

4.
Heliyon ; 10(5): e27232, 2024 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-38455590

RÉSUMÉ

The Atlantic forest is one of the world's major tropical biomes due to its rich biodiversity. Its vast diversity of plant species poses challenges in floristic surveys. Fourier transform infrared spectroscopy (FTIR) enables rapid and residue-free data collection, providing diverse applications in organic sample analysis. FTIR spectra quality depends on the sample preparation methodology. However, no research on FTIR spectroscopy methodology for taxonomy has been conducted with tropical tree species. Hence, this study addresses the sample preparation influence on FTIR spectra for the taxonomic classification of 12 tree species collected in the Serra do Mar State Park (PESM) - Cunha Nucleus - São Paulo State, Brazil. Spectra were obtained from intact fresh (FL), intact dried (DL), and heat-dried ground (GL) leaves. The spectra were evaluated through chemometrics using Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Linear Discriminant Analysis (LDA) with validation by LDA-PCA. The results demonstrate that sample preparation directly influences tropical species FTIR spectra categorization capability. The best taxonomic classification result for all techniques, validated by LDA-PCA, was obtained from GL. FTIR spectra evaluation through PCA, HCA, and LDA allow for the observation of phylogenetic relationships among the species. FTIR spectroscopy proves to be a viable technique for taxonomic evaluation of tree species in floristic exploration of tropical biomes which can complement traditional tools used for taxonomic studies.

5.
Glob Chang Biol ; 30(3): e17206, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38445332

RÉSUMÉ

Symbiotic nitrogen (N) fixation (SNF), replenishing bioavailable N for terrestrial ecosystems, exerts decisive roles in N cycling and gross primary production. Nevertheless, it remains unclear what determines the variability of SNF rate, which retards the accurate prediction for global N fixation in earth system models. This study synthesized 1230 isotopic observations to elucidate the governing factors underlying the variability of SNF rate. The SNF rates varied significantly from 3.69 to 12.54 g N m-2 year-1 across host plant taxa. The traits of host plant (e.g. biomass characteristics and taxa) far outweighed soil properties and climatic factors in explaining the variations of SNF rate, accounting for 79.0% of total relative importance. Furthermore, annual SNF yield contributed to more than half of N uptake for host plants, which was consistent across different ecosystem types. This study highlights that the biotic factors, especially host plant traits (e.g. biomass characteristics and taxa), play overriding roles in determining SNF rate compared with soil properties. The suite of parameters for SNF lends support to improve N fixation module in earth system models that can provide more confidence in predicting bioavailable N changes in terrestrial ecosystems.


Sujet(s)
Écosystème , Fixation de l'azote , Biomasse , , Sol
6.
Am J Bot ; 110(8): e16219, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37561649
7.
PhytoKeys ; 229: 131-138, 2023.
Article de Anglais | MEDLINE | ID: mdl-37485010

RÉSUMÉ

Amorphophallussakonnakhonensis Chatan & Promprom, a new species from northeastern Thailand, is described and illustrated. The new species is most similar to A.harmandii Engl. & Gehrm. and A.linearis Gagnep., but it is distinguished by the combination of characters as follows: clear differences with A.harmandii are shorter style; disc-like, slightly smooth surface, concave centre, ca. 0.2 × 0.1 mm stigma; slightly cylindrical, slightly narrower upper part of staminate flower zone; slightly cylindrical to elongate-fusiform, erect or slightly erect, creamy white appendix. The clearly distinct morphology with A.linearis are disc-like, slightly smooth surface, concave centre, ca. 0.2 × 0.1 mm stigma; elliptic or obovate leaflet; 1-3 cm long, creamy white appendix. The preliminary conservation status was assessed, and the distinct characteristics of similar species were discussed.

8.
PhytoKeys ; 218: 19-27, 2023.
Article de Anglais | MEDLINE | ID: mdl-36762269

RÉSUMÉ

Raphiocarpustaygiangensis, a new species of Gesneriaceae family discovered in Tay Giang District, Quang Nam Province, Central Vietnam, is here described and illustrated. The new species is diagnosed by the combination of its stem up to 2 m long, sericeous hairs on young stem, leaf petiole and adaxial mid-vein, sparsely and minutely serrate leaf margin, axillary inflorescence spreading along stem, sparsely long gland-tipped hairs on peduncle, pedicel, calyx, outside corolla and pistil, calyx 5-disparted from base, purplish white flower with purple stripes inside corolla tube, and dish-shaped stigma formed by 2 semi-orbicular lobes horizontally expanding. Distinct features of the new species and its morphologically closest congener, Rhaphiocarpusaxillaris, are compared and discussed. The conservation status of the described species is estimated as Vulnerable (VU D2) according to the IUCN Red List Criteria.

9.
Ecology ; 104(2): e3909, 2023 02.
Article de Anglais | MEDLINE | ID: mdl-36326547

RÉSUMÉ

Plant element stoichiometry and stoichiometric flexibility strongly regulate ecosystem responses to global change. Here, we tested three potential mechanistic drivers (climate, soil nutrients, and plant taxonomy) of both using paired foliar and soil nutrient data from terrestrial forested National Ecological Observatory Network sites across the USA. We found that broad patterns of foliar nitrogen (N) and foliar phosphorus (P) are explained by different mechanisms. Plant taxonomy was an important control over all foliar nutrient stoichiometries and concentrations, especially foliar N, which was dominantly related to taxonomy and did not vary across climate or soil gradients. Despite a lack of site-level correlations between N and environment variables, foliar N exhibited intraspecific flexibility, with numerous species-specific correlations between foliar N and various environmental factors, demonstrating the variable spatial and temporal scales on which foliar chemistry and stoichiometric flexibility can manifest. In addition to plant taxonomy, foliar P and N:P ratios were also linked to soil nutrient status (extractable P) and climate, especially actual evapotranspiration rates. Our findings highlight the myriad factors that influence foliar chemistry and show that broad patterns cannot be explained by a single consistent mechanism. Furthermore, differing controls over foliar N versus P suggests that each may be sensitive to global change drivers on distinct spatial and temporal scales, potentially resulting in altered ecosystem N:P ratios that have implications for processes ranging from productivity to carbon sequestration.


Sujet(s)
Écosystème , Forêts , États-Unis , Azote/analyse , Sol , Climat , Phosphore/analyse , Feuilles de plante/composition chimique
10.
BMC Plant Biol ; 22(1): 382, 2022 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-35909100

RÉSUMÉ

BACKGROUND: The genus Daucus (Apiaceae) comprises about 40 wild species and the cultivated carrot, a crop of great economic and nutritional importance. The rich genetic diversity of wild Daucus species makes them a valuable gene pool for carrot improvement breeding programs. Therefore, it is essential to have good knowledge of the genome structure and relationships among wild Daucus species. To broaden such knowledge, in this research, the nuclear DNA content for 14 Daucus accessions and four closely related species was estimated by flow cytometry and their pollen morphology was analyzed by light and scanning electron microscopy (SEM). RESULTS: The flow cytometric analysis showed a 3.2-fold variation in the mean 2C values among Daucus taxa, ranging from 0.999 (D. carota subsp. sativus) to 3.228 pg (D. littoralis). Among the outgroup species, the mean 2C values were 1.775-2.882 pg. The pollen grains of Daucus were tricolporate, mainly prolate or perprolate (rarely) in shape, and mainly medium or small (rarely) in size (21.19-40.38 µm), whereas the outgroup species had tricolporate, perprolate-shaped, and medium-sized (26.01-49.86 µm) pollen grains. In the studied taxa, SEM analysis revealed that exine ornamentation was striate, rugulate, perforate, or the ornamentation pattern was mixed. At the time of shedding, all pollen grains were three-celled, as evidenced by DAPI staining. We also found high positive correlations between the length of the polar axis (P) and the length of the equatorial diameter (E) of pollen grains, as well as between P and P/E. However, when comparing cytogenetic information with palynological data, no significant correlations were observed. CONCLUSIONS: This study complements the information on the nuclear DNA content in Daucus and provides comprehensive knowledge of the pollen morphology of its taxa. These findings may be important in elucidating the taxonomic relationships among Daucus species and can help in the correct identification of gene bank accessions. In a broader view, they could also be meaningful for the interpretation of evolutionary trends in the genus.


Sujet(s)
Apiaceae , Daucus carota , Apiaceae/génétique , Daucus carota/génétique , Taille du génome , Microscopie électronique à balayage , Amélioration des plantes , Pollen/anatomie et histologie , Pollen/génétique
11.
Microsc Res Tech ; 85(6): 2162-2180, 2022 Jun.
Article de Anglais | MEDLINE | ID: mdl-35238102

RÉSUMÉ

The current study analyzed the epidermal morphology of Asparagaceae in detail and assessed its systematic importance. At the familial level, no consistent characteristics were found, but anticlinal wall and stomata morphology provided systematic information of different tribes, especially Ophiopogoneae and Polygonateae. In Ophiopogoneae, Liriope and Ophiopogon had similar epidermis, which implying a close relationship between them, and was also supported by related studies. The leaves of Polygonateae exhibited rounded and undulate anticlinal wall. Polygonatum arisanense var. formosanum had a rounded anticlinal wall, whereas other species exhibited undulate anticlinal walls. Different epidemis of Po. arisanense var. formosanum supported the variety treatment of Po. arisanense. The intergeneric relationship was also interpreted based on the anticlinal wall and stomata. Therefore, the epidermis could provide the systematic value of Asparagaceae. The present study also revealed the linkage of stomata and habitat types, though the adaptative significance of epidermal traits needs further study. RESEARCH HIGHLIGHTS: Anticlinal wall and stomatal morphology had systematic potential on tribal or generic levels of Asparagaceae. Stomatal types of Asparagaceae might be linked to environmental factors.


Sujet(s)
Asparagaceae , Épiderme végétal , Épiderme , Microscopie électronique à balayage , Épiderme végétal/anatomie et histologie , Feuilles de plante/anatomie et histologie , Stomates de plante , Taïwan
12.
PhytoKeys ; 211: 33-44, 2022.
Article de Anglais | MEDLINE | ID: mdl-36760725

RÉSUMÉ

Hydrangeamarunoi Tagane & S. Fujii, from the Kimotsuki Mountains in the Ohsumi Peninsula, southern Japan, is described and illustrated. It is morphologically similar to H.alternifolia in having three-petaloid calyx lobes in marginal flowers, but is distinguished by the larger stamen number, and longer styles and seeds. Multiplex ISSR genotyping by sequencing (MIG-seq) demonstrated that the new species is monophyletic and closely related to H.amamiohsimensis and H.moellendorffii rather than H.alternifolia.

13.
PhytoKeys ; 183: 108-114, 2021.
Article de Anglais | MEDLINE | ID: mdl-34754264

RÉSUMÉ

Hemiboeachanii, a new species of Gesneriaceae from Ha Giang Province, northern Vietnam, is here described and illustrated. It has many branched stems, diamond-shaped involucre with two cirrose opposite apices, a pink corolla, red spotted inside, and a flowering time in January-February. Among congeners with an externally hairy corolla, this new species is morphologically close to H.crystallina and H.sinovietnamica. Diagnostic discriminative characters in all mentioned species are discussed. The conservation status of this species is considered to be "Critically endangered" (CR) according to the IUCN Red List Categories and Criteria.

14.
Preprint de Portugais | SciELO Preprints | ID: pps-2175

RÉSUMÉ

Phaseoleae s.l. comprises the largest tribe of subfamily Papilionoideae in number of genera, with 89 genera and 1,567 species. Regional taxonomic studies of the tribe are only occasional in Brazil and rare in Northeastern Brazil, including Bahia, the region's most species-rich state. In this context, the present study had as its objective to carry out a taxonomic study of the species of Phaseoleae s.l. occurring in Caetité (BA), a conservation priority region for the Caatinga vegetation. For this purpose, we made field expeditions and visited to the HUNEB-Collection Caetité and HUEFS Herbaria. A total of 25 species and 15 genera were recorded, accounting for 23% of the species registered for Bahia. Caetité stands out as one of the main centers of floristic richness of Phaseoleae s.l. in the semi-arid region of Bahia state. Leaflet shape, inflorescence type and the coloration of the petals and seeds are the most useful characters for identification.


Phaseoleae s.l. é a maior tribo de Papilionoideae em número de gêneros, com 89 e 1.567 espécies. Os estudos taxonômicos regionais da tribo são pontuais no Brasil e raros no Nordeste do Brasil, incluindo a Bahia, o Estado mais rico em espécies da região. Neste contexto, este trabalho teve como objetivo realizar o tratamento taxonômico das espécies de Phaseoleae s.l. ocorrentes em Caetité (BA), uma região de prioridade de conservação para a vegetação de Caatinga. Para tanto, foram realizadas expedições de coleta e visitas aos Herbários HUNEB-Coleção Caetité e HUEFS. Um total de 25 espécies e 15 gêneros foi registrado, o que representa 23% das espécies registradas para a Bahia. Caetité destaca-se como um dos principais centros de riqueza florística de Phaseoleae s.l. no semiárido baiano. O formato dos folíolos, tipo de inflorescência e a coloração das pétalas e das sementes são os caracteres mais úteis na identificação dos táxons.

15.
J Allergy Clin Immunol Pract ; 9(7): 2642-2644, 2021 07.
Article de Anglais | MEDLINE | ID: mdl-33741508

RÉSUMÉ

The diagnosis and treatment of atopic disorders associated with specific aerobiological triggers require basic botanical training. However, the identification of specific pollen can often be confounded by broad naming conventions that range from categorized colloquial to scientific names based on either higher taxonomic levels or, in some cases, binomial nomenclature. Physicians specializing in allergy often lack a comprehensive understanding with respect to plant taxonomy and botanical nomenclature that are critical skills required for clinical practice and research programs evaluating pollen and airborne fungal spores. In addition, binomial and current family designation and synonyms, including author citation are often misused, causing a misinterpretation of existing plants species or pollen types. It is critical that the correct botanical name is linked to a validated specimen and scientific naming conventions are used where possible by the clinician and researcher. In relation to pollen identification, we propose that clinicians and researchers should provide the currently accepted binomial nomenclature, offer relevant synonyms, and use the Angiosperm Phylogeny Group names.


Sujet(s)
Plantes , Pollen , Humains
16.
Saudi J Biol Sci ; 28(1): 512-522, 2021 Jan.
Article de Anglais | MEDLINE | ID: mdl-33424334

RÉSUMÉ

Aizoaceae is one of the most important and widespread succulent plant families in both tropical/subtropical regions and arid zones. In this study, 27 species were collected from various floristic regions in Egypt, Kingdom of Saudi Arabia and cactus farms (Kalupia - Egypt). The morphological characteristics of every taxon were recorded. The important morphological features included: the number of leaves per plant; leaf types; leaf position (cauline or radical; the latter indicates leaves arising from, or near, the roots); leaf arrangement; petiolate or sessile leaves; leaf sheath present or absent; leaf shape; leaf margin; leaf tip; presence of leaf 'window area'; leaf texture; and presence of white or dark miniscule dots (white miniscule dots from calcium carbonate and dark miniscule dots from tannin sacs). The investigated anatomical features were as follows: shape of the transverse section; the type of epidermal cells; the presence of large epidermal cells (bladder cells); presence of papilla and simple hairs; presence of tannin sacs; shapes of calcium oxalate crystals; shape of the xylem vessels; and the presence of Kranz unit (the unit that constitutes the vascular bundle/s, parenchyma sheath, and surrounding mesophyll) or collenchyma sheath. All data were recorded in a data matrix (as either text or numerical data), which was used to construct the identification key and phylogeny tree using a multi-variate statistical package. The results of our analysis may open the possibility of using the morphological and anatomical features of leaves to distinguish between the subfamilies, genera, and species of Aizoaceae.

17.
Microsc Res Tech ; 84(4): 682-694, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33105053

RÉSUMÉ

Palynology gives the evidence for identification and elimination of taxonomically complex genera. Pollen morphology of nine species (three subg., three sect.) of the genus Cephalaria Schrad. was studied using light microscopy and scanning electron microscopy. Pollen grains of all investigated species are triporate, suboblate to subprolate (P/E = 0.75-1.28), and large-sized (P = 58.52 µm-114.38, E = 63.84-119.70 µm). The outline of pollen grains in equatorial view is circular or elliptic, in polar view circular, circular-triangular, or triangular. Pores are distinct, lolongate, elliptic, or circular, with an annulus, operculum, and distinct or indistinct, wide halo surrounding the aperture. Exine sculpture is echinate-microechinate or echinate-microechinate-nanoechinate. Additional diagnostic characters at the species level in Cephalaria Schrad. that can be used for the purposes of taxonomy are size of pollen grains and pores, the shape of pores, the width of the annulus, structure of the exine, dimension of echini and microechini, location of microechini, and presence/absence of nanoechini. Palynomorphological data are compared with the taxonomical classification system of investigated taxa. It is shown that pollen grains morphology of the genus Cephalaria Schrad. is similar to the pollen morphology of the genus Dipsacus L., which confirms their inclusion in the Dipsaceae tribe.


Sujet(s)
Caprifoliaceae , Dipsacaceae , Microscopie électronique à balayage , Pollen
18.
Methods Mol Biol ; 2222: 39-55, 2021.
Article de Anglais | MEDLINE | ID: mdl-33301086

RÉSUMÉ

This chapter presents an overview of the major plant DNA sequences and molecular methods available for plant taxonomy. Guidelines are provided for the choice of sequences and methods to be used, based on the DNA compartment (nuclear, chloroplastic, mitochondrial), evolutionary mechanisms, and the level of taxonomic differentiation of the plants under survey.


Sujet(s)
Codage à barres de l'ADN pour la taxonomie , Plantes/classification , Plantes/génétique , Codage à barres de l'ADN pour la taxonomie/méthodes , Codage à barres de l'ADN pour la taxonomie/normes , Variations de nombre de copies de segment d'ADN , ADN des chloroplastes , ADN mitochondrial , ADN des plantes , Évolution moléculaire , Génome végétal , Génomique/méthodes , Séquences répétées d'acides nucléiques
19.
Methods Mol Biol ; 2222: 1-38, 2021.
Article de Anglais | MEDLINE | ID: mdl-33301085

RÉSUMÉ

Taxonomy is the science that explores, describes, names, and classifies all organisms. In this introductory chapter, we highlight the major historical steps in the elaboration of this science, which provides baseline data for all fields of biology and plays a vital role for society but is also an independent, complex, and sound hypothesis-driven scientific discipline.In a first part, we underline that plant taxonomy is one of the earliest scientific disciplines that emerged thousands of years ago, even before the important contributions of the Greeks and Romans (e.g., Theophrastus, Pliny the Elder, and Dioscorides). In the fifteenth-sixteenth centuries, plant taxonomy benefited from the Great Navigations, the invention of the printing press, the creation of botanic gardens, and the use of the drying technique to preserve plant specimens. In parallel with the growing body of morpho-anatomical data, subsequent major steps in the history of plant taxonomy include the emergence of the concept of natural classification , the adoption of the binomial naming system (with the major role of Linnaeus) and other universal rules for the naming of plants, the formulation of the principle of subordination of characters, and the advent of the evolutionary thought. More recently, the cladistic theory (initiated by Hennig) and the rapid advances in DNA technologies allowed to infer phylogenies and to propose true natural, genealogy-based classifications.In a second part, we put the emphasis on the challenges that plant taxonomy faces nowadays. The still very incomplete taxonomic knowledge of the worldwide flora (the so-called taxonomic impediment) is seriously hampering conservation efforts that are especially crucial as biodiversity has entered its sixth extinction crisis. It appears mainly due to insufficient funding, lack of taxonomic expertise, and lack of communication and coordination. We then review recent initiatives to overcome these limitations and to anticipate how taxonomy should and could evolve. In particular, the use of molecular data has been era-splitting for taxonomy and may allow an accelerated pace of species discovery. We examine both strengths and limitations of such techniques in comparison to morphology-based investigations, we give broad recommendations on the use of molecular tools for plant taxonomy, and we highlight the need for an integrative taxonomy based on evidence from multiple sources.


Sujet(s)
Plantes/classification , Biodiversité , Évolution biologique , Codage à barres de l'ADN pour la taxonomie , Phénotype , Plantes/anatomie et histologie
20.
PhytoKeys ; 167: 31-43, 2020.
Article de Anglais | MEDLINE | ID: mdl-33304117

RÉSUMÉ

A new species of Eriotheca (Malvaceae, Bombacoideae) from coastal areas in the northeastern Brazilian states of Alagoas and Bahia is described and illustrated. Eriotheca alversonii inhabits Atlantic coastal forest and is found principally on sandy soils in restinga vegetation. It is most similar morphologically to E. parvifolia. Both species have 3-foliolate leaves and short petioles on fertile branches, but the new species has smaller flowers, truncate to crenulate calyces, and smaller globose to subglobose capsules. The affinities of E. alversonii to morphologically similar species and its phenology are discussed. A distribution map and preliminary assessment of its conservation status are provided.

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