Gayana Botanica

King Penguin Nature Reserve Flora: criteria and narratives as a proposal for selecting charismatic plants

Osvaldo Vidal — 2023-08-19

The King Penguin Nature Reserve (KPNR) in Bahía Inútil (Strait of Magellan, Chile), protects the only King Penguin nesting colony (Aptenodytes patagonicus) that exists in Chile, and represents one of the most visited ecotourism resources in Chilean Tierra del Fuego Island. The vegetation in the area is dominated by the Patagonian steppe, a desert landscape where tiny plants stand out, with showy flowers and whose food, ritual and medicinal use was well known by the hunter-gatherer Selk’nam people. Despite the important milestone that the KPNR represents, the tourist information offered there is restricted to the King penguin, omitting the potential narratives that can be elaborated from the vegetal landscape and ethnographic memory. In this study, the vascular flora of the KPNR was inventoried, and an exhaustive review of scientific literature was carried out to evaluate the potential of this biodiversity in the elaboration of a complementary narrative for ecotourism. On the basis of aesthetic, ecological, distributional, ethnobotanical and historical criteria, 12 of the 85 registered species were selected for the preparation of narratives. In this study, we propose that the selected criteria may be useful to elaborate a story, but the quality of the content will depend on the available scientific research. Also, we suggest that narratives integrating charismatic plants, their ethnobotanical uses, ecological and historical context, can be complementary tools to improve the contents of ecotourism in the KPNR, interpreting the natural history of the area and thus, enrich the visitor’s experience for a better knowledge of a heritage until now, undervalued.

Effects of UV-B radiation on the morphology, UV-B absorbing compounds and photosynthetic pigment content of Plantago lanceolata and Rheum rhabarbarum

Roberto Niculcar — 2023-08-19

In recent decades the fluence of ultraviolet-B (UV-B) radiation striking the ground has increased as a consequence of ozone depletion at southern latitudes. This phenomenon has sparked much interest in unravelling how plants acclimate to this condition. UV-B radiation triggers several responses that affect plant physiology, morphology and biochemistry. In this study, the effects of supplemental UV-B radiation on plant architecture, UV-B absorbing compounds and photosynthetic pigments were analyzed in two cosmopolitan species. A different range of responsiveness was found in the morphological parameters (leaf area, length and width; plant height) of species. The effects on photosynthetic pigment content and the UV-B absorbing compounds were studied through absorbance measurements. The obtained data showed that only carotenoids increased in irradiated plants of R. rhabarabarum. Likewise, an increase in the UV-B absorbing compounds content was found in irradiated plants from the same species. This effect may be regarded as a chemical protection against the damaging effects of light in photosynthesis and against oxidative cell damage. UV-B radiation induced photomorphogenic responses. In fact, all the morphological parameters of P. lanceolata were increased. The clear increase shown in leaf size and plant height suggest that cell division and stem elongation and/or differentiation processes are stimulated by UV-B radiation. These changes can be seen as an eustress effect and may indicate that plants are physiologically adapted to this level of UV-B radiation.

Peaty wetlands of the Nahuelbuta National Park (Araucanía Region), compared with others in a latitudinal Chilean gradient

Carlos Ramírez — 2023-08-19

Peat bogs are wetlands characterized as swamps of very extreme cold and wet places. In Chile there are several types of them: sphagnum bogs (minerotrophic), pulvinated bogs (ombrotrophic), grassy bogs, shrubby bogs and wooded bogs. This work was carried out in the peat bogs of the northern limit of them areal, in Nahuelbuta National Park, located in the Cordillera de la Costa approximately 1200 to 2300 m above sea level between the Regions of Bío-Bío and Araucanía, Chile. The flora was studied with traditional methods and the vegetation with phytosociological methodology and the results were confirmed with multivariate classification and ordination statistics. The vascular, moss and lichenic flora showed little floristic richness, only 38 species. All the flora species are native and six of them are endemic. This flora gives rise to four new peaty plant associations for Chile: two pulvinate-bogs (Myrteolo-Donatietum fasciculariae and Gaultherio-Oreoboletum obtusangulae), one sphagnum-bogs (Carici- Sphagnetum magellanicii) and one grassy-bogs (Bacharido-Festucetum scabriusculae). When comparing the peat bogs studied with those further south, the donatia pulvinate-bogs appear to be more homogeneous than the sphagnum peat bogs, in fact, the former share five species and the latter, only two. In general, a greater variation of the pulvinated peat bogs was found in the Aysén Region and of the sphagnum bogs in the Chiloé Region, the latter coming out of the conglomerate formed by the other four places. It was confirmed that in both latitudinal extremes the peat bogs are poorer in species and the greatest richness occurs in the intermediate regions.

After more than a century in oblivion, a species in Dysopsis (Euphorbiaceae) resurfaces

Jose Murillo A. — 2023-08-19

Morphological and molecular characters have been used to reassess species limits within Dysopsis, resulting in an improved delimitation of taxa. D. chilensis, a taxon long considered a synonym of D. glechomoides, is reestablished; the genus now consists of four species. Lectotypes for three species have been designated. Also included are descriptions of the species and a diagnostic identification key.

Changes in the composition and diversity of urban trees in Linares, Nuevo León

Eduardo Alanís-Rodríguez — 2023-08-19

Urban trees offer important environmental services in cities, which is why their establishment and study has increased in recent years. In this work, the change in the composition and diversity of urban trees was evaluated in the small city of Linares, Nuevo León in a period of 26 years (1995 2021). For this, crown coverage was measured, and the Shannon diversity and Morisita-Horn similarity indices were obtained. As results, 62 species (22 native and 40 introduced) belonging to 56 genera and 29 tree families were recorded throughout the evaluated period. The best represented families were Fabaceae with 9 species, Fagaceae, Oleaceae and Rutaceae with 4 and Apocynaceae and Moraceae with 3. An increase in the density of introduced trees was observed from 1995 to 1999, while by 2021 those of native origin increased significantly as was the case with Quercus fusiformis and Fraxinus udhei. The highest species similarity was recorded in the 1995-1999 period (69,2 %) with shared species such as the exotic Ficus benjamina and Ligustrum japonicum. The current arboreal flora in the public areas of Linares is probably the result of a greater knowledge of the ecology of both native and introduced species by society, as well as the academic and governmental institutions of Linares, Nuevo León.

The family Gleicheniaceae (Polypodiopsida) in Argentina and Paraguay

Saúl Páez — 2023-09-27

A study of the Gleicheniaceae family in Argentina and Paraguay is presented, covering taxonomic, morphological and distribution aspects. Eight herbaria from both countries and the digital type specimens were reviewed. The morphological characters and sculpture of the spores were analyzed and described. This family is characterized by its pseudodichotomically divided fronds, with buds located at the internal angle of each division. Four species of the genera Dicranopteris (D. flexuosa), and Sticherus (S. cryptocarpus, S. lanuginosus, S. quadripartitus) were recorded. The distribution of D. flexuosa is widened in Argentina. A key for the determination of species, morphological descriptions, brief descriptions of spores, illustrations, maps of geographical distribution and ecological comments are given.

Obituary: Claudio Donoso Zegers

Rómulo Santelices-Moya — 2023-08-19

Chromindex-UdeC, a simple method for calculating karyotypic asymmetry indices from Excel tables generated bythe MicroMeasure program

Carlos Baeza Perry — 2023-08-19

MicroMeasure es un programa científico de análisis de imágenes, cuya aplicación está destinada a estudios citológicos, citogenéticos y citotaxonómicos. Este programa está diseñado específicamente para la medición lineal de los cromosomas utilizando fundamentalmente el centrómero de cada cromosoma como punto crucial para la medición de los dos brazos de cada uno de ellos. Los datos se calculan automáticamente, dando como resultado una hoja de cálculo Excel. A partir de esta tabla Excel, se pueden hacer una multiplicidad de cálculos, dependiendo de las necesidades e intereses de cada investigador. Chromindex-UdeC permite utilizar tablas Excel múltiples, generadas por el programa MicroMeasure y solo deben ser subidas al servidor para calcular automáticamente los índices de asimetría disponibles(A₂, AsK%, CVCL, CVCI,MCA, Syi, %TF). Este programa puede ser usado en español y/o en inglés y no se necesita ninguna experiencia en programación, es gratis, está disponible en una plataforma abierta a todo público y se actualiza automáticamente.