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Background and aims: The Funga of the Patagonian Nothofagus forests is being studied since the late 19th century, but despite many efforts is still far from being completely known. The aim of this paper is to present detailed descriptions and data on geographical distribution of some genera and species of mitosporic ascomycetes that constitute new records for Argentina and for the Neotropical Region. M&M: Bark and woody debris from native Nothofagaceae were collected and studied. Reproductive structures were hand-sectioned and examined following traditional mycological techniques. Results: Six species of mitosporic ascomycetes were identified: Avettaea salvadorae, Bactrodesmium atrum, Dwiroopa ramya, Gilmaniella multiporosa, Monodictys paradoxa and Pycnopeziza quisquiliaris. Full descriptions, comments on identification and data on distribution and habitat of each species are provided, along with photographs illustrating diagnostic features. Conclusions: Two genera, Dwiroopa and Pycnopeziza, and one species, M. paradoxa, are registered for the first time in the Neotropical Region, two other species are first recorded in South America (B. atrum and G. multiporosa). This constitutes the second record of A. salvadorae in the continent, thus expanding its area of distribution. [ABSTRACT FROM AUTHOR]

Background and aims: During the study of the bryoflora of Bogotá, individuals of Syntrichia papillosa were found in urban localities. The aim of this contribution is to confirm the presence of this epiphytic species to the Colombian flora. Materials and methods: Living plants and herbarium material from the Natural History Museum (BM), the New York Botanical Garden (NY) and Jardín Botánico José Celestino Mutis (JBB) herbaria, were analyzed. Recently collected specimens were deposited in JBB. Results: A conspectus of the morphological features of the species based on herbarium specimens are provided, along with morpho-anatomical photographs. Further, the presence of the species in different localities belonging to the area around Bogotá was confirmed. Conclusion: This paper confirms the presence of Syntrichia papillosa in the surroundings of Bogotá. This species is known from Asia, Australia, Europe, New Zealand, North America, Africa, Argentina, Bolivia, Brazil, Colombia, Chile, and Ecuador. Thus, the genus Syntrichia is represented in Colombia by eight taxa: S. andicola, S. bogotensis, S. breviseta, S. fragilis, S. kingii, S. lacerifolia, S. laevipila and S. papillosa. [ABSTRACT FROM AUTHOR]

Introduction and objectives: The genus Pilosella is native to Europe and Asia, but its species are successful invaders on most continents. These species form an agamic complex with common apomixis. Apomictic species hybridize and have different degree of residual sexuality. Main aim of this paper was to determine if interspecific hybridization already occurred in Patagonia. M&M: We analysed seed progeny collected at thirteen populations of Pilosella in southern Argentina and Chile. The taxonomic identity of plants, DNA ploidy level (using flow cytometry), chromosome number, reproduction, formation of parthenogenetic seeds and clonal identity (using isozyme phenotypes) were examined. Results: No mixed-species population was recorded. Two apomictic clones of P. officinarum (one pentaploid and the other hexaploid) were found in populations: eight were hexaploid and one was mixed in cytotype composition. A new species for Patagonia, the apomictic pentaploid P. caespitosa, was represented by plants from two Argentinean populations. Some of the progeny plants, cultivated from seeds sampled at three localities, represented seed-fertile aneuploids the morphology of which suggest a hybrid origin with P. officinarum as one of the parental species. Conclusions: The presence of seed-fertile, aneuploid and parthenogenetic hybrids among the cultivated plants signifies an increased risk of the formation of new hybridogeneous genotypes of Pilosella in southern Patagonia. [ABSTRACT FROM AUTHOR]

Background and aims: In 2013, blooms similar to those produced by Didymosphenia geminata (Lyngbye) M. Schmidt around the world, were detected in the Grande River basin, Tierra del Fuego province, and in 2014 in de las Vueltas River in Santa Cruz province. The aim of this paper is to analyze the valve morphology and morphometry of these materials to establish if they correspond to D. geminata or to other species of the genus that is producing the massive growth in southern Patagonia. M&M: Samples were collected at Grande River in 2013 and 2015 and, in de las Vueltas River in 2015 and 2016. Samples were analyzed with light and electron microscopy. For morphometric analyses 100 specimens from each sample were measured and statistical analyses were carried out using the R statistical package. Results: The studied populations have the same fine morphology described for other populations collected in Patagonia. Nevertheless, in some sampling sites from Santa Cruz province, we found a morphotype with a markedly smaller size, subcapitated poles, little marked constrictions of the poles, a broad central area (relative to cell size) and 1 to 3 stigmata, that was never reported in South America. Conclusions: The studied populations correspond to D. geminata ssp. geminata Metzeltin & Lange-Bertalot. From a morphological point of view the smaller morphotype present in Santa Cruz belongs to the same subspecies but can be easily misidentified during the routine monitoring programs carried out with light microscope due its size and valve outline. [ABSTRACT FROM AUTHOR]

Background and aims: Bonamia Thoaurs (Convolvulaceae) comprises about 70 species with a tropical and subtropical distribution. Morphological and molecular studies in Bonamia were carried out to clarify relationships in and out of the genus and throughout this work it was detected the need for re-limit the circumscription of some taxa. This paper contributes to the circumscription and lectotypification of Bonamia sericea (Griseb.) Hallier f., an endemic species from northern Argentina. M&M: Morphological analysis of Bonamia sericea, were made based on a study of specimens of herbaria, including the type-material, digital type images and other herbaria website. Results: A new synonym for B. sericea is proposed. The lectotype of B. sericea is here designated and a complete description and illustrations are presented. [ABSTRACT FROM AUTHOR]

Background and aims: Our current knowledge about Moqoit medical ethnobotany is scarce, that is why the aim of this paper seeks to identify the medicinal plants and its therapeutic indications registered in the field among present moqoit people from Chaco province. These data are also compared with the few historical data available, as well as with the medical ethnobotany of Argentinian Gran Chaco criollos people and surrounding areas. M&M: Between 2008 and 2018, a total of 11 (eleven) campaigns were carried out to the Moqoit settlements in Chaco province, where semi-structured interviews were carried out with key collaborators. With these key people, herbarium samples were collected from the plants they have indicated. Results: A total of 381 medicinal applications are registered about 155 botanical taxa. Most of them (28%) are prescribed against digestive disorders and in a lesser extent, against dermatological conditions (15%), as antipyretics (14%) and for the reproductive system (13%). Frequently plants are used against "empacho" (digestive disorder), affections of magical-religious etiology (therapeutic rituals), as refreshing, antitussive and against toothache. Conclusions: The results from the comparisons made show the presence of cultural loans from criollos groups -by location and stock- to Moqoit medical ethnobotany, mostly from the Hispanic-Quichua criollos bio-cultural complex. [ABSTRACT FROM AUTHOR]

This paper analyses daily and seasonal variations on pollen concentrations and the influence of meteorological conditions on the airborne pollen from June 2011 to May 2014. Data is also compared with results from a previous pollen survey from 2000-2001. Ninety-three taxa were identified, belonging to 49 trees and shrub taxa and 44 herbaceous taxa. The most important pollen sources were Poaceae, Platanus, Cupressaceae/Taxaceae, Eupatorieae type, Celtis, Urticaceae, Myrtaceae, Casuarina, Amaranthaceae, Cyperaceae, Fraxinus, Arecaceae, Ricinus communis, Moraceae, Myrsine, Ambrosia, Quercus, and Pinaceae. Pollen was recorded all year round but the main pollen season was from August to April. Inter-annual differences were observed on pollen indexes, dates and values of daily peak concentrations and monthly accumulated concentrations. Temperature, relative air humidity and wind speed and direction seem to be the most influential meteorological variables on pollen concentrations. The number of days that pollen concentrations are above moderate and high thresholds levels is estimated and woody and non-woody pollen concentrations would be above moderate levels on average 182 days per year. [ABSTRACT FROM AUTHOR]

Morphological variability of the nanoplanktonic diatom Thalassiosira laevis from coastal waters of Province of Buenos Aires (Argentina). Despite the fact that the genus Thalassiosira was previous and extensively studied including ultrastructural analysis of species found in phytoplanktonic samples collected from marine waters of Argentina, nanoplanktonic species have been frequently overlooked. This paper is devoted to show the morphological variation of Thalassiosira laevis, a nanoplanktonic species collected from marine coastal waters of the Province of Buenos Aires, to compare Argentinean material with those from China, Korea and Brazil described in the literature, and to record it for the first time from Argentina. [ABSTRACT FROM AUTHOR]

The herbarium LE of the Komarov Botanical Institute in Saint Petersburg (former Leningrad), Russia holds one of the least known Brazilian moss collections in the world. In this paper we provide a list the Brazilian types of mosses deposited in the type collection of LE. Totaling types for 41 species names from Brazil are listed. [ABSTRACT FROM AUTHOR]

In this paper we examine the leaf-blade anatomy of: Commelina erecta L. var. erecta f. erecta, Tradescantia fluminensis Vell., Tripogandra diuretica (Mart.) Handlos, and T. glandulosa (Seub.) Rohweder. These species grow in the coastal region of the Río de la Plata (Argentina) where they are used as ophthalmic, diuretic, antirheumatic, sudorific, and digestive. The aim of this study was to establish diagnostic features in order to deepen knowledge of these medicinal species and thus, get a valuable tool to establish their botanical identity. The leaves were prepared according to usual methods for light and scanning electron microscopes. Histochemical techniques to identify starch, lipophilic substances, mucilage, tannins, and oxalate salts were performed. The ions analysis of oxalate salts using a scanning electron microscope equipped with an energy dispersive spectrometer was performed. The main differential traits found were: stomata hexaperiginous in C. erecta var. erecta f. erecta, and tetraperigenous in T. fluminensis and Tripogandra species; leaf blade margins with parenchyma in C. erecta var. erecta f. erecta and T. fluminensis, and with fibers in Tripogandra species; presence of druses in palisade parenchyma of the blade in T. fluminensis, and the hairy index. [ABSTRACT FROM AUTHOR]

In many plant species, ethylene and gibberellins interact to regulate plant growth and development. In some cases, these hormones can act in a synergistic way whereas in others they can be antagonistic. To date, the control of hypocotyl elongation by ethylene and gibberellins has been poorly explored in tomato. In this paper, we report that, application of exogenous ethylene to tomato seedlings or high endogenous ethylene production, as in the epinastic mutant, strongly prevent the effect of gibberellic acid (GA3 ) application. Moreover, constitutive activation of gibberellin signal in a DELLA deficient mutant is not able to counteract the inhibitory effect of ethylene on hypocotyl elongation, suggesting that ethylene acts independently from DELLA-mediated gibberellin response. Interestingly, when ethylene perception is blocked, the GA3 promotive effect on hypocotyl length is less effective, indicating that the presence of a basal level of ethylene could synergistically enhance hypocotyl growth. Taken together, these observations may suggest that, in tomato, supraoptimal concentrations of ethylene are able to antagonize gibberellin effect but normal levels seem to promote gibberellin-induced hypocotyl elongation. [ABSTRACT FROM AUTHOR]