Aim
Factors affecting bromeliad distribution depend on the life forms of the studied species; some could grow as terrestrial, saxicolous, or epiphytic depending on the type of habitat. We analysed ...the distribution patterns of the life forms of a bromeliad species in different biogeographic domains and associated them with environmental variables and vegetation types.
Location
Chaquenian, Amazonian, and Seasonally Dry Tropical Forest domains; South America.
Taxon
The tank bromeliad Aechmea distichantha (Bromeliaceae: Bromelioideae).
Methods
We compiled records of the biogeographic distribution and the vegetation types where A. distichantha occurs based on bibliographic data, digital datasets, herbaria, and personal observations. We associated the distributional records of this species with altitude, five selected bioclimatic variables, four soil variables, and with the vegetation types where it occurs.
Results
A. distichantha has been recorded as epiphytic, terrestrial and saxicolous in all biogeographic domains but showed contrasting patterns in life form proportions among them. In the Amazonian domain, characterized by evergreen tropical and subtropical forests with high precipitation, it mainly grows as epiphytic. In the Chaquenian domain, dominated by xerophytic forests with low rainfall, high soil pH and base saturation, it mainly grows as terrestrial, whereas in the Seasonally Dry Tropical Forest domain, the three life forms were recorded in similar proportions. In azonal plant communities of all domains, it mainly grows as saxicolous.
Main Conclusions
This tank bromeliad species can thrive in sites with contrasting habitat and environmental conditions. Its ability to survive in different environments could be associated with its high frost tolerance, the presence of the CAM photosynthetic pathway, a well‐developed phytotelma, and high phenotypic plasticity. The life form prevailing in each domain is influenced by water availability (i.e., the quantity of water available during each year, the precipitation in the driest month, and the plant water supply relative to demand).
•AMF populations fromCr(VI) polluted soil belong to Rhizophagus & Paraglomus genera.•Plants re-exposed to Cr(VI) had 60-70% mycorhizal intensity with all AMF populations.•Shoot Cr concentration ...doubled in non-AMF vs. AMF plants; the content was similar.•AMF vesicles percentage negatively correlated with Cr root concentration.•Paraglomus, an early diverging genus, seems to be best adapted to Cr(VI).
In a global context of climate change and loss of biodiversity, phytoremediation appears as a viable strategy to recover polluted soil. Phytoremediation is defined as a strategy to recover polluted soils by means of plants and the associated microorganisms. Arbuscular mycorrhizal fungi (AMF) are one of the most widespread soil microorganisms, they live in symbiosis with 70% of terrestrial plants. In the symbiotic relation, the fungal partner incorporates carbohydrates and lipids facilitated by the plant and the plant incorporates minerals facilitated by the fungal partner. Then, the inclusion of AMF in phytoremediation strategies should become a priority, not only because the presence of AMF will help the plant to adapt to the polluted soil but also because it could enhance the incorporation of carbon to the soil. In addition, the actual context of global biodiversity loss prioritizes the study of local populations in order to promote the incorporation of the local biodiversity to soil management, that includes phytoremediation. In the present work we aimed to taxonomically characterise four AMF populations obtained from Ricinus communis rhizospheric Cr(VI) polluted soil. In addition, we aimed to study the symbiosis and the mineral uptake of some elements, including phosphorus and chromium, in R. communis plants associated with each AMF population and re-exposed to Cr(VI). We found that three AMF populations grouped near Rhizophagus and one near Paraglomus accessions and that the four AMF populations were tolerant to the re-exposure to 8 ppm Cr(VI) substrate concentration. Finally, from the mineral content analysis, our results strongly suggest that Paraglomus sp., a taxon which appeared earlier in the evolution of AMF, was the population that best adapted to the re-exposure of 8 ppm Cr(VI). Thus, we suggest that future phytoremediation studies should include taxa from this early diverged genus.
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Introducción y Objetivos: Ruprechtia apetala (Polygonaceae) es una especie que presenta una gran variabilidad morfológica entre individuos a lo largo de su rango de distribución. El presente estudio ...tiene como objetivo evaluar dicha variabilidad morfológica dentro del territorio argentino.
M&M: se colectaron 42 individuos en seis provincias argentinas correspondientes a las regiones Chaqueña serrana, Selva Pedemontana y a la zona de transición entre ellas. Fueron analizados numerosos caracteres morfológicos, tanto vegetativos como reproductivos. Se realizaron Análisis de Componentes Principales y de Conglomerados para detectar morfogrupos; estos últimos se evaluaron mediante análisis univariados (Prueba de Kruskal-Wallis y descripción de clusters mediante R) y multivariados (ANOSIM y PERMANOVA), para evaluar posibles diferencias intraespecíficas significativas. Adicionalmente, se confeccionó un mapa de distribución biogeográfica de los individuos.
Resultados: a partir del análisis multivariado se detectaron dos grupos morfológicos, principalmente a niveles foliar y de hábito de crecimiento. Los Análisis ANOSIM y PERMANOVA muestran que existe una diferencia global significativa entre ambos grupos (p-valor < 0,05); no obstante, los estadísticos correspondientes indican una elevada similitud entre ellos. Adicionalmente, mediante la descripción de cada conglomerado, se corroboró que no existen estados de caracteres mutuamente excluyentes para uno u otro grupo.
Conclusiones: La variabilidad morfológica encontrada entre ejemplares de distintas regiones biogeográficas, y la no exclusividad de caracteres morfológicos para cada grupo particular, permite postular la existencia de ecotipos en la especie.
This study provides a preliminary phylogeny of the
Celtis
species from the neotropical region with emphasis on the South American species. We analyzed 19 taxa using the plastid
psbA
-
trn
H and ...nuclear ITS 4-5, and
FA16180
b markers. The sequence data were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. The South American species were highly supported as monophyletic, while the North American species were recovered as paraphyletic. The endocarp morphology corroborated the lineages within the molecular phylogeny and helps to differentiate the species, to recognize a new species
Celtis serratissima
, and to reestablish two previously known species,
Celtis clausseniana
(Wedd.) Miq. and
Celtis spinosissima
(Wedd.) Miq. These three species emerged among one of the three lineages of the tropical South American species.
Celtis serratissima
is thus described, illustrated, and compared to its most closely related species.
El género Celtis L. (Celtidaceae) comprende unos 70 taxones de árboles o arbustos de regiones templadas y tropicales. En la Argentina habitan cuatro especies, todas pertenecientes al subgénero ...Mertensia Planch., cuya similitud y variabilidad inter e intraespecíficas han generado confusiones taxonómicas dentro del grupo. Un caso emblemático es el de C. pallida Torr. y C. tala Gillies ex Planch., considerados sinónimos de C. ehrenbergiana (Klotzsch) Liebm. Como estas entidades son claramente diferenciables a campo, se realizó la revisión taxonómica de dichos taxones. Tras un extenso muestreo, un estudio morfológico detallado y a través de un Análisis de Componentes Principales y de Conglomerados, se concluyó que lo considerado en Argentina como C. ehrenbergiana, abarca tres entidades: C. tala, C. pallida var. pallida y C. pallida var. discolor Hunz. & Dottori, y se propone la rehabilitación de dichos taxones. Asimismo, los resultados de los Análisis de la Varianza y de Similitud corroboran diferencias significativas (p-valor < 0.05) entre grupos. Se establecieron como caracteres de mayor importancia taxonómica: porte de los individuos, textura de corteza, pilosidad de láminas, nervaduras y pecíolos, espinas estipulares/ramas espinosas, abundancia y aspecto de domacios. Además, algunos especímenes de C. pallida son morfológicamente intermedios entre ambas variedades, por lo cual su identidad será esclarecida por medio del uso de herramientas moleculares.
The Anacardiaceae is an important and worldwide distributed family of ecological and socio-economic relevance. Notwithstanding that, molecular studies in this family are scarce and problematic ...because of the particularly high concentration of secondary metabolites—i.e. tannins and oleoresins—that are present in almost all tissues of the many members of the group, which complicate the purification and amplification of the DNA. The objective of this work was to improve an available DNA isolation method for
Schinopsis
spp. and other related Anacardiaceae, as well as the PCR protocols for DNA amplification of the chloroplast
trn
L-F,
rps
16 and
ndh
F and nuclear ITS–ETS fragments. The modifications proposed allowed the extraction of 70–120 µg of non-degraded genomic DNA per gram of dry tissue that resulted useful for PCR amplification. PCR reactions produced the expected fragments that could be directly sequenced. Sequence analyses of amplicons showed similarity with the corresponding
Schinopsis
accessions available at GenBank. The methodology presented here can be routinely applied for molecular studies of the group aimed to clarify not only aspects on the molecular biology but also the taxonomy and phylogeny of this fascinating group of vascular plants.
Durante el estudio monográfico del género Schinopsis (Anacardiaceae) se realizó una revisión nomenclatural de sus especies y sinónimos. Se lectotipifican los nombres Schinopsis brasiliensis, ...S. brasiliensis var. glabra, S. heterophylla, S. marginata y S. peruviana y se indican algunos casos de lectotipificaciones desapercibidas en trabajos previos. Se designa un epitipo para S. haenkeana, entidad considerada hasta ahora como taxón dudoso.
RESUMEN El género Schinopsis Engl. (Anacardiaceae) tiene ocho especies, de las cuales en el presente trabajo se describen palinológicamente a S. balansae Engl., S. boqueronensis Mogni & Oakley, S. ...cornuta Loes., S. haenkeana Engl., S. heterophylla Ragonese & J.A. Castigl. y S. lorentzii (Griseb.) Engl. Las muestras se tomaron de individuos en su ambiente natural y de ejemplares disecados. Los granos de polen fueron acetolizados y se estudiaron mediante microscopía de luz y electrónica de barrido. Estos son isopolares, radiosimétricos, con forma suboblato, esferoidal, prolato-esferoidal y prolato, de ámbito subcircular, subtriangular o triangular lobado; zonotremos, tricolporados y con endoaperturas lalongadas, de tamaño pequeño a mediano, con diámetro polar de 18-36 µm y diámetro ecuatorial de 16-28 µm. La exina es semitectada, estriada a supraestriada-infrarreticulada. Esta caracterización palinológica aporta nueva información, la que en combinación con el estudio de otros caracteres, contribuye a la delimitación taxonómica de las especies chaqueñas de Schinopsis Engl., principalmente S. haenkeana de S. lorentzii.
RESUMO O gênero Schinopsis Engl. (Anacardiaceae) tem oito espécies, das quais, no presente trabalho descrevem-se palinologicamente, a S. balansae Engl., S. boqueronensis Mogni & Oakley, S. cornuta Loes., S. haenkeana Engl., S. heterophylla Ragonese & J.A. Castigl. e S. lorentzii (Griseb.) Engl. As amostras foram coletadas de indivíduos em seu ambiente natural e de exemplares dissecados. Os grãos de pólen foram acetolisados e estudados por microscopia eletrônica de varredura. Estes são isopolares, radiossimétricos, com forma suboblata, esferoidal, prolato-esferoidal e prolato, de âmbito pequeno a mediano, com diâmetro polar de 18-36 μm e um diâmetro equatorial de 16-28 μm. A exina é semitectada, estriada a supraestriada-infrarreticulada. Essa caracterização palinológica fornece novas informações que, em combinação com o estudo de outros caracteres, contribui para a delimitação taxonômica das espécies chaquenhas de Schinopsis Engl., principalmente S. haenkeana de S. lorentzii.
Infraspecific classification and geographical distribution of Monvillea phatnosperma (Cactaceae). Some aspects of morphology, taxonomy and nomenclature about Monvillea phatnosperma (K. Schum.) ...Britton & Rose (Cactaceae), a species native from the north of the ‘Great Chaco’ and adjacent areas, are considered. M. phatnosperma var. arenasii var. nov. is described and ilustrated in replacement of Monvillea kroenleinii R. Kiesling –nom. inval
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