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Within Chloridoideae, subtribe Eleusininae comprises 237 species with little morphological diversity in its inflorescence structure. This diversity may be explained by an evolution from complex (pyramidal shaped and highly branched) to simpler (digitated and barely branched) morphologies. However, only mature specimens have been studied; the developmental analyses of the inflorescences are rare. We analyzed the inflorescence, spikelet, and flower development of 17 species belonging to subtribe Eleusininae using scanning electron microscopy. In the early stages of the transition to flowering of the studied species, the inflorescence meristem elongates initiating primary branches acropetally. The differentiation of these branches along the main axis is either basipetal or amphipetal. Though the initiation of secondary branches along primary branches may be acropetal or amphipetal, their differentiation follows an amphipetal direction. The florets within spikelets are initiated acropetally. We found abnormal orientation of stamens and gynoecium within florets of Leptochloa chloridiformis. The analysis of the ontogeny enriched the current knowledge of inflorescences of the subtribe. In addition, the developmental patterns revealed the existence of more than one developmental pattern that leads to similar mature inflorescence forms. The results serve for future efforts on postulating trends of developmental patterns along Poaceae. Fil: Muchut, Sebastián Elías. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pilatti, Vanesa. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Reutemann Arnolfo, Andrea Guadalupe. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vegetti, Abelardo Carlos. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Reinheimer, Renata. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentina

Physalis is an economically important and morphologically diverse genus of plants with solitary flowers and fruits that are enveloped by an inflated fruiting calyx. Although work to resolve phylogenetic relationships in this clade is ongoing, Physalis remains a taxonomically complex genus with multiple nomenclatural problems. Here, we review 28 species from the United States and their synonyms as well as clarification on the status of their types. We propose 53 typifications. We select a lectotype for 49 names and a neotype for three names (P. ixocarpa, P. linkiana, P. ramosissima). We additionally designate an epitype for P. longifolia. Fil: Pretz, Chelsea. University of Colorado; Estados Unidos Fil: Deanna, Rocío. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. University of Colorado; Estados Unidos

Cinco lectotipos y dos neotipos son aquí designados para siete especies de Nototriche, como parte del estudio del género para la flora de Sudamérica: N. holosericea, N. megalorrhiza, N. meyeni, N. pseudoglabra, N. sajamensis, N. saltensis y N. transandina. Se brindan, además, notas sobre las tipificaciones. Five lectotypes and two neotypes are here designated for seven species in Nototriche, as part of the ongoing study of the genus for the South American flora: N. holosericea, N. megalorrhiza, N. meyeni, N. pseudoglabra, N. sajamensis, N. saltensis, and N. transandina. Notes about these typifications are also provided. Fil: Cialdella, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

The small Neotropical tribe Liabeae (Compositae) is currently classified into four subtribes: Liabinae, Munnoziinae, Paranepheliinae, and Sinclairiinae. As currently accepted, Paranepheliinae includes seven genera, Chionoppapus, Erato, Microliabum, Paranephelius, Philoglossa, Pseudonoseris, and Stephanbeckia, distributed especially throughout the Andes from Venezuela and Colombia to Argentina. Our research focuses in the genus Microliabum, which inhabits extra‐Andean enviroments from Bolivia to central Argentina. The broad concept of Microliabum and its phylogenetic position within Paranepheliinae are controversial. Bayesian and maximum parsimony analyses of ribosomal nuclear ITS and plastid trnL‐F suggest that both subgenera described within Microliabum are monophyletic. However, Microliabum, without the subgenus Austroliabum, is close to Stephanbeckia. A statistical analysis (PCoA) supports the separation of the subgenera, and morphology mainly based on traits of the involucre and florets permits to establish new taxonomical circumscriptions. Thus, the reinstatement of Austroliabum, the more southern Liabean genus, is here proposed. The genus includes three endemic species from Sub‐Andean and Pampean Hills in central and northwestern Argentina. Austroliabum is characterized by white‐tomentose or woolly pubescence on stems and abaxial leaf surfaces, acrodromous leaf venation, campanulate involucres, coriaceous and adpressed phyllaries in usually five series, outer phyllaries shorter than the inner ones, style branches of disc florets shorter than the pubescent part on the shaft below the bifurcation point, style pubescence on the shaft below the bifurcation point of disc florets at least three times longer than the branches of the style, persistent 2‐seriate pappus with outer series of scales and inner series of barbellate bristles, and achenes pubescent on the ribs. In addition, a revision of Microliabum s.str., with three species, is carried out., This work was supported by the Myndel Botanical Foundation (grants 2005 and 2006), the Agencia Nacional de Promoción Científica y Tecnológica (Secretaría de Ciencia y Técnica [PICT 2006 # 35064 and 2012 # 01683]), Comisión Nacional de Investigaciones Científicas y Técnicas, CONICET (PIP 2013/2015 # 0446, 2017/2019 # 11220170100421CO;P-UE 2017/2021 # 22920160100098CO) and Universidad Nacional de La Plata (I + D N/687 and N/814), Argentina to DGG and MAG, and the Ministerio de Ciencias, Tecnología e Innovación Productiva (Argentina) and the Fundación Carolina (Spain) to DGG (grant for a short research stay at the Botanical Institut of Barcelona, 2007).

The New World genus Heterosperma Cav. is circumscribed to include 11 species: H. achaetum S. F. Blake, H. diversifolium Kunth, H. ferreyrii H. Rob., H. mexicanum (A. Gray ex S. Watson) Lizarazu & S. E. Freire, H. nanum (Nutt.) Sherff, H. ovale S. F. Blake, H. ovatifolium Cav., H. pinnatum Cav., H. spathulatum S. F. Blake, H. tenuisectum (Griseb.) Cabrera, and H. trilobum S. F. Blake. Heterosperma is described as having a usually herbaceous habit, pinnatisect or entire leaves, radiate capitula, and heteromorphic cypselae. The following taxa are newly synonymized: Coreopsis L. sect. Anathysana S. F. Blake with Heterosperma; H. maritimum Kunth var. hirsuta Hieron. with H. ovatifolium; and H. maritimum var. latifolia Hieron. with H. spathulatum. Lectotypes are here designated for H. maritimum var. hirsuta, H. pinnatum var. typicum Kuntze, H. tagetinum A. Gray, H. spathulatum, and H. maritimum var. latifolia. A key to the species of the genus is provided, as well as morphological descriptions, illustrations, and distribution maps. A detailed morphological study of trichomes and pappus is also presented. Fil: Freire, Susana Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Lizarazu, Mabel Angela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

Introducción y objetivos: Ligaria cuneifolia (Loranthaceae) posee una amplia distribución desde Perú al centro de Argentina y Uruguay. Esta especie habita en tres regiones geográficas en forma disyunta a lo largo de cordillera de los Andes, las Sierras Centrales de Argentina y en el este de Sudamérica, en Uruguay y sur de Brasil. El objetivo de este trabajo fue determinar el rango de hospedadores de Ligaria cuneifolia en toda su distribución geográfica y analizar el uso de hospedadores en cada una de las regiones geográficas (Andes, Centro y Este). M&M: Se registró el uso de hospedadores de Ligaria cuneifolia y distribución geográfica en base a ejemplares depositados en herbarios. Resultados: En total se registraron 35 especies de hospedadores nativos, comprendidas en 22 géneros y 12 familias. Además se registaron 11 especies no nativas en todas las areas. Los géneros de hospedadores con mayor número de registros fueron Schinus, Prosopis, Geoffroea, Larrea y Vachellia. Conclusiones: El uso de hospedadores no estuvo directamente asociado a las áreas geográficas. La región Andes fue la que presentó una mayor diversidad de especies, géneros y familias de hospedadores. Background and aims: Ligaria cuneifolia (Loranthaceae) has a wide geographic distribution from Peru to the center of Argentina and Uruguay. It inhabits three disjunct regions, one along the Andes, Sierras Centrales of Argentina and towards the East in Uruguay and south of Brazil. The objective of this study was to determine the host range of Ligaria cuneifolia in all the distribution range; and to analyze host use in each of the geographic regions (Andes, Center and East). M&M: hosts use and geographical distribution of Ligaria cuneifolia was recorded on the basis of specimens deposited in herbaria. Results: A total of 35 native host species were recorded as hosts. In addition, 11 non-native host species were recorded in all area. The genera with higher number of records were Schinus, Prosopis, Geoffroea, Larrea y Vachellia. Conclusions: Host use was not directly related to geographic area. The Andes region was the one that had the most host diversity at the species, genera and family level. Fil: Amico, Guillermo Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Vidal Russell, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

A group of seven endemic Polystichum species inhabit Patagonia, the southern region of South America. To date, evolutionary relationships of these Austral South American Polystichum remain unknown. The biota of the Southern Andes appears to be more closely related to the temperate Australasian species than to northern South American ones. Differences in morphological characters suggested that Austral South American Polystichum follows that biogeographical pattern, not being closely related to their congeners in the Northern and Central Andes. We sought to reveal the evolutionary relationships, estimate the divergence times and reconstruct both ancestral areas and ancestral ploidy levels of Austral South America Polystichum. Phylogenetic relationships were estimated using maximum likelihood and Bayesian approaches. The seven Austral South American species plus 31 Polystichum species spanning all other major biogeographic regions were sampled for three DNA markers. Divergence times were estimated in BEAST and Bayesian binary Markov chain Monte Carlo reconstruction was applied in order to infer ancestral areas. The evolution of ploidy was reconstructed on the maximum clade credibility tree, using stochastic character mapping. Austral South American Polystichum was recovered as monophyletic. The earliest divergence reconstructed within the Austral South American Clade was that of Polystichum andinum; subsequently two other lineages diverged comprising the remaining Austral South American species. The Austral South American lineage is not closely allied to North and Central Andes congeners. Long-distance dispersal of an ancestral tetraploid from Australasia during the late Miocene is the most likely explanation for the origin of Patagonian Polystichum. Then, Pliocene and Pleistocene orogenic and climatic changes may have shaped its diversification in Patagonia. Fil: Morero, Rita Ema. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Deanna, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Barboza, Gloria Estela. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Barrington, David S.. University of Vermont; Estados Unidos

Fil: Rojas, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Botánica del Nordeste; Argentina. Fil: Rojas, José Luis. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina. Fil: Keller, Héctor Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico (Nordeste). Instituto de Botánica del Nordeste; Argentina. Fil: Keller, Héctor Alejandro. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina. El género Styrax incluye cerca de 130 especies leñosas. Para la Argentina han sido registradas dos especies. En la presente contribución una tercera especie, Styrax acuminatus, es citada por primera vez para la provincia de Misiones. Se provee una descripción de la especie, fotografías de campo, observaciones ecológicas, un mapa de distribución y una clave para distinguir a las especies de Styrax presentes en la Argentina. Styrax is a genus of woody plants with about 130 species. In Argentina two species has been recorded. In the present contribution, a third species, Styrax acuminatus, is reported for the first time for the province of Misiones. A description of the species, field pictures, ecological observations, a distribution map, and a key to the species of Styrax in Argentina are provided.

The high environmental heterogeneity of large fluvial systems is reflected by the co-existence of contrasting plant communities and landforms. The main objective of this study was to assess the forest diversity changes in islands of the Middle Paraná River (Argentina) in order to discuss an integrative question: how synchronized are the major changes in the features of islands and forests? Persistence age, elevation and flood regime of 11 main channel islands were determined. Variables related to the vascular plant community and the tree stand structure of forests were also measured in 400 m2 plots. Islands were classified as young or old (YIs or OIs), according to their persistence age, which ranged from two to 108 years. Both island classes differed in their elevation but not in the proportion of low water phase. Only three out of nine tree species were dominant: Tessaria integrifolia and Croton urucurana (restricted to YIs and OIs, respectively), and Salix humboldtiana (distributed in both island classes). Alpha diversity was positively correlated with the age of the YIs and reach the highest value in the oldest island forest. Beta diversity was mainly due to processes of species replacement which differentiate floodplain forests. Gamma diversity reached 101 species, being the perennial herbs aclear majority. The stand structure and the complete floristic composition were significantly different between YIs and OIs, with three and seven indicator species of each island class, respectively. Considering integrative models ofsuccession, our findings suggest that the biogeomorphic phase, recognised by the fluvial biogeomorphic model, prevailed in the whole range of island persistence ages. Therefore, it seems that the increase in forest diversity in a large river is restricted to spatial refugia defined by major hydrogeomorphic shifts. Fil: Brumnich, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral; Argentina Fil: Marchetti, Zuleica Yael. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral; Argentina Fil: Pereira, María Soledad. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Anther and gynoecium structure and embryological information in Koelreuteria and Sapindaceae as a whole remain understudied, as well as the evolution of imperfect flowers in the latter. The aims of this study were to analys in K. elegans subsp. formosana the anther and gynoecium structure and the development of male and female gametophytes in the two floral morphs of putatively imperfect flowers. Standard techniques were applied for LM and SEM. Compared to the normal anther development in staminate flowers, a delayed programmed cell death of tapetum, septum and middle layers on the onset of microspore stage result in indehiscent anthers in the functionally pistillate flowers. Orbicules are reported for the first time in Sapindaceae. Gynoecium development in functionally pistillate flowers is normal, whereas in functionally staminate ones a pistillode with degenerated ovules at the tetrad stage is formed. The pollen tube transmitting tract consists of one layer of epithelial cells with a small lumen in the style and ovary. The anatomy of the latter revealed an axile placentation and complete septum. Reproductive characters of Koelreuteria shared with other Sapindaceae taxa are a secretory binucleate tapetum, simultaneous cytokinesis, unicellular stigmatic papillae, Polygonum type megagametophyte with ephemeral antipodals, and ovules campylotropous, with funicular obturator and amphistomic micropyle. Imperfect flowers in the family are triggered by defective sporophytic tissues impacting on the normal development of microspores and megaspores, disrupting embryological events in staminate and pistillate organs at different developmental stages. Reconstructing ancestral character state under parsimony revealed that two ovules per locule, absence of obturator, presence of hypostase, and binucleate tapetum may be regarded as plesiomorphic for Sapindaceae. These analyses have provided information on the evolution of embryological characters in the family and its phylogenetic significance. Fil: Avalos, Adan Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Zini, Lucia Melisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Ferrucci, María Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Lattar, Elsa Clorinda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Cephalanthus belongs to Rubiaceae tribe Naucleeae, and is characterized as shrubs to a small trees, mainly from the lowlands, with verticillate leaves. We hypothesized that the foliar morphoanatomy of Cephalanthus species provides characters informative to our taxonomic study, and that their leaves present adaptations to waterlogged habitats. To test these hypotheses our aims were to describe the macro- and micromorphology and anatomy of leaves in all Cephalanthus species. We describe and characterize leaf disposition, shape, size of blade and petiole, characteristics of the epidermis and indumenta, including the micromorphology of the cuticle and stomata, and the types of leaf domatia, if present. The anatomy of the petiole and leaf blade was also analyzed, including the mesophyll, vascular systems, ontogeny of the stomata, presence and typification of oxalate of calcium crystals, and their distribution in the foliar tissues. Uniformity in the morphoanatomical characters allows us to define the genus Cephalanthus, but inside this uniformity we can also differentiate between the species by means of a dichotomous key. The presence of domatia in pockets in C. occidentalis, in contrast to the tuft of hairs in C. salicifolius and C. tetrandrus, shed light on the taxonomic delimitation of the former because historically they were considered a single species. Cephalanthus species show variability in micromorphological characters, but have a strong uniformity in anatomical organization. The leaves of Cephalanthus show adaptations to seasonal environments; some are typical hydromorphic traits while other reflect adaptations to their heliophilic habitat and tolerance to dry periods. Fil: Romero, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Salas, Roberto Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

The Morelloid Clade, also known as the black nightshades or "Maurella" (Morella), is one of the 10 major clades within the mega-diverse genus Solanum L. The clade is most species rich in the central to southern Andes, but species occur around the tropics and subtropics, some extending well into the temperate zone. Plants of the group are herbaceous or short-lived perennials, with small white or purplish white flowers, and small juicy berries. Due to the complex morphological variation and weedy nature of these plants, coupled with the large number of published synonyms (especially for European taxa), our understanding of species limits and diversity in the Morelloid Clade has lagged behind that of other major groups in Solanum. Here we provide the second in a three-part series of revisions of the morelloid solanums treating the species occurring in North and Central America and the Caribbean (for the Old World see "PhytoKeys 106", the third part will treat species of South America). Synonymy, morphological descriptions, distribution maps, and common names and uses are provided for all 18 species occurring in this region. We treat 10 of these species as native, and eight as putatively naturalised, introduced and/or invasive in the region. We provide complete descriptions with nomenclatural details, including lecto- and neotypifications, for all species. Keys to all species occurring in the whole region and for each area within it (i.e., North America, Central America and Mexico, and the islands of the Caribbean), illustrations to aid identification both in herbaria and in the field, and distribution maps are provided. Preliminary conservation assessments are provided for all species. Details of all specimens examined are provided in three Supplementary materials sections. Fil: Knapp, Sandra. Natural History Museum; Reino Unido Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Bohs, Lynn. University of Utah; Estados Unidos Fil: Sarkinen, Tina. University of Edinburgh; Reino Unido

Petroravenia was until recently considered as a genus of three species (P. eseptata, P. friesii, and P. werdermannii) distributed along the Central Andes of Argentina, Bolivia, Chile, and Peru. This genus was included in the tribe Thelypodieae and was morphologically characterized by being tiny rhizomatous perennial herbs with rosulate leaves, dendritic trichomes, capsular silicles, and incumbent cotyledons. However, the phylogeny of Petroravenia, and its tribal placement, was never analyzed using molecular data. The lack of such studies, as well as the paucity of herbarium collections, suggesting that Petroravenia species are vulnerable and/or endangered, prompted us to address the molecular phylogeny of this genus. For this purpose, we generated comprehensive molecular phylogenies using nuclear (ITS) and plastid (trnL‐F and trnH‐psbA) data, and conducted morphological comparisons between these species and their closest related taxa. Results from the phylogenetic analyses showed that Petroravenia represents a polyphyletic group, with P. eseptata included in tribe Halimolobeae, and P. friesii and P. werdermannii placed within tribe Eudemeae and related to the genus Alshehbazia. Based on the results obtained from morphological and molecular data, we decided herein to retain the original circumscription of Petroravenia as monospecific within the tribe Halimolobeae and to transfer P. friesii and P. werdermannii to the genus Alshehbazia within the tribe Eudemeae. Systematic implications of these results are also discussed. Fil: Salariato, Diego Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Al-Shehbaz, Ihsan. Missouri Botanical Garden; Estados Unidos

Sugarcane (Saccharum officinarum) is one of the most important crops inthe world and a major source of sugar for human consumption. Despite this immense value, the circumscription of the genus Saccharum is complex, contentious, and largely unresolved. Saccharum is accepted in a broad sense by some authors or split into various genera such as Erianthus and Tripidium. A plastome phylogenomic analysis of sugarcane and relatives was performed in order to investigate generic delimitation, with emphasis on Tripidium (= Erianthus sect. Ripidium). Our plastome phylogenomics clearly demonstrates that Saccharum s.l. is polyphyletic and Tripidium (distributed in Old World) belongs to a distinct lineage from Saccharum s.s. (Old World) and Erianthus s.s. (= Erianthus sect. Erianthus, New World). Therefore, the present analysis confirms the recognition of Tripidium as a distinct genus from Saccharum and Erianthus, which is also supported by morphology and nuclear markers. The circumscription of Erianthus s.s. remains unclear since our plastome phylogenomics is consistent with either considering it as a distinct genus or including it in Saccharum. Better understanding of the evolutionary relationships of sugarcane and relatives may be useful for the selection of potential taxa for interspecific and intergeneric crosses in the genetic improvement of sugarcane. A taxonomic treatment of the six species of Tripidium is also presented, including descriptions, illustrations, data on geographical distribution, and three new nomenclatural combinations. Fil: Welker, Cassiano A. D.. Universidade Federal de Uberlândia; Brasil Fil: McKain, Michael R.. University of Alabama at Birmingahm; Estados Unidos Fil: Vorontsova, Maria S.. Royal Botanic Gardens; Reino Unido Fil: Peichoto, Myriam Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Kellogg, Elizabeth Anne. Donald Danforth Plant Science Center; Estados Unidos

Otachyriinae Butzin, one of the three subtribes within the Paspaleae tribe of grasses, includes seven genera and approximately 35 species. Interestingly, this subtribe comprises species with C3, C3-C4 intermediate, and C4 photosynthesis. The circumscription of Otachyriinae has changed through time, and still varies among treatments in current use. The monophyly of this subtribe has been recovered in previous studies based on plastid markers. A phylogenetic study taking into account polyploidy and a low-copy nuclear gene (LCNG) is still lacking in Paspaleae. A phylogeny including data from a LCNG is paramount to uncover reticulated evolution within the group. The purpose of the present study was to reconstruct the evolutionary history of Otachyriinae, based on both chloroplast and LCNG DNA with a focus on polyploidization. Several incongruences between gene trees allowed us to explore relationships between diploid and polyploid taxa. Our study identified several promising topics for future studies: genetic allopolyploidy and autopolyploidy was here documented using the characteristic pattern of double-labelled gene trees. The molecular evidence indicates that at least 40% of species of Otachyriinae show phylogenetic signature of polyploidy (16 taxa appear double-labelled in the nuclear gene trees); furthermore, the results support an allopolyploid origin of at least nine taxa in the subtribe: Rugoloa polygonata, a species with unknown photosynthetic pathway, the proto-kranz species Steinchisma laxum and Rugoloa hylaeica, and the C3 species Hymenachne felliana, H. grumosa, H. hemitomon, H. donacifolia, H. pernambucense, and P. grande. Also, our results confirm that the C4 genus Anthaenantia is unambiguously monophyletic and show that Anthaenantia lanata is an autopolyploid. We recognized six genera within subtribe Otachyriinae: Anthaenantia, Hymenachne, Otachyrium, Plagiantha, Rugoloa, and Steinchisma. Finally, Panicum species with historically ambiguous placements, i.e. P. condensatum, P. grande, P. harleyi, P. leptachne, P. longum, and P. stagnatile were transferred to the genus Hymenachne. Fil: Acosta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Reinheimer, Renata. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentina

In addition to the degree of geographical isolation (sympatry, parapatry, allopatry and peripatry), ecology can be an important factor promoting diversification of lineages, both by niche divergence as well as niche conservatism. Tetraglochin is a genus of shrubs with six species distributed along the Southern and Central Andes, from Peru to southern Argentina and central Chile. Although monophyly of the genus as the identity of its species are well established, spatiotemporal framework for its diversification and the potential role of the ecology and geography in the speciation process remain unknown. In the present study we analyzed diversification times and historical biogeography of the genus, and conducted different climatic niche and geographical range comparisons among its species to determine possible patterns associated with speciation. Results support the Pleistocene diversification, early along the Southern Andes and the Patagonian Steppe and subsequently in the Central Andes. Climatic niche divergence did not prove to be a major factor promoting speciation, but rather the phylogenetic niche conservatism. Our analyses also favored the sympatric model of speciation, although patterns from geographical range evolution are difficult to interpret due to the lability on the ancestral distributions, and therefore micro-allopatric or parapatric divergence associated with the glacial-interglacial cycles and climatic oscillations throughout the Quaternary should not be discarded. Other potential factors associated with diversification of Tetraglochin are also discussed. Fil: Salariato, Diego Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Acosta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Cialdella, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

Macrofossil impressions of caytonialean leaves and micro- and megasporangiate organs from the Early Jurassic Taquetrén locality in Patagonia, Argentina, are described based on more than 300 hand specimens. Leaves of the organ-genus Sagenopteris are described using both discrete and continuous features allowing us to erect the species Sagenopteris trapialensis sp. nov. Associated microsporangiate organs of Caytonanthus type are the first recorded for South America and are characterized by a unique combination of architecture, size and type of dehiscence. Two specimens, one resembling an isolated Caytonia cupule, and the other a Caytonia axis, are also described. The availability of a collection with numerous specimens has proven to be an important tool in order to fully understand the intraspecific morphological plasticity of the studied species. The striking morphological resemblance of both vegetative and reproductive organ-genera with their Northern Hemisphere counterparts suggests that they were part of the same lineage, which was widely distributed during the Jurassic. Well-defined whole-plant concepts are still needed to advance the goal of deciphering the internal relationships of caytonialeans in particular, and their relationships with other groups of seed-plants in general, and thorough macro-morphological characterization of the organs that compose them, as we present here, may be of valuable use in achieving it. Fil: Elgorriaga, Andres. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Escapa, Ignacio Hernán. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Cúneo, Néstor Rubén. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Pepper (Capsicum L.) is a major vegetable and spice crop worldwide. Global production of both fresh and dried fruit continues to increase steadily in terms of area harvested and yield. Various topics are addressed in this review, including recent additions to and clarification of Capsicum taxonomy, genetic resources of Capsicum, cytogenetic studies, the current status of our understanding of the mechanisms affecting the biosynthesis of capsaicinoids, the use of gene mutations to elucidate carotenoid biosynthetic pathways and their regulation, and recent advances in whole-genome sequencing and assembly. Fil: Jarret, Robert L.. United States Department of Agriculture; Estados Unidos Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Costa Batista, Fabiane Rabelo da. Instituto Nacional Do Semiarido; Brasil Fil: Berke, Terry. Seminis Vegetable Seed; Estados Unidos Fil: Chou, Yu-Yu. Genetic Resource And Seed Unit; China Fil: Hulse-Kemp, Amanda. United States Department of Agriculture; Estados Unidos Fil: Ochoa-Alejo, Neftali. Centro de Investigacion y de Estudios Avanzados; México Fil: Pasquale, Tripode. Council for Agricultural Research and Agricultural Economics Analysis ; Italia Fil: Veres, Aniko. Szent Istva University; Hungría Fil: Carrizo Garcia, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Csillery, Gabor. Budakert Ltd; Hungría Fil: Huang, Yung-Kuang. The World Vegetable Center; China Fil: Kiss, Erzsebet. Szent Istvan University; Hungría Fil: Kovacs, Zsofia. Szent Istvan University; Hungría Fil: Kondrak, Mihaly. Szent Istvan University; Hungría Fil: Arce-Rodriguez, Magda Lisette. Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional; México Fil: Scaldaferro, Marisel Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Szoke, Antal. Szent Istvan University; Hungría

Blechnum malacothrix, hasta el momento conocida sólo de Perú y Bolivia, se registra por primera vez para el noroeste de Argentina. Con este hallazgo el número de especies de la familia Blechnaceae en este país asciende a 23, la mayoría de las cuales crece en el norte. Se presenta una descripción de Blechnum malacothrix, junto con ilustraciones, un mapa del nuevo sitio de colección y una clave para identificar las especies de Blechnum que crecen en el noroeste argentino. Blechnum malacothrix, until now known from Peru and Bolivia, is registered for the first time in northwestern Argentina. With this finding the number of species of the Blechnaceae in this country ascends to 23, most of them growing in the north. A description of Blechnum malacothrix, together with illustrations of the specie, a map with the new collection site, and a key to identify the species of Blechnum growing in northwestern Argentina are presented. Fil: Jarsún, Adrián Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Chambi, Cristina Janet. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina Fil: Martinez, Olga Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina

The essential oil composition of Bothriochloa velutina has been studied. The principal compounds of essential oils of three South American endemics, B. eurylemma, B. meridionalis and B. velutina were isolated. In laboratory bioassays, the principal compounds inhibited the seed germination and root and shoot growth of lettuce (Lactuca sativa L.), maize (Zea mays L.), wintergreen paspalum (Paspalum guenoarum Arechav.) and lovegrass [Eragrostis curvula (Schard.) Nees] test species. The aqueous extracts from different plant parts of three species of Bothriochloa inhibited the seed germination and root and shoot growth of test species. Aqueous extracts were more inhibitory to shoot and root elongation than to seed germination. Significant inhibition in shoot length at all concentrations indicated the phytotoxic activity of extracts. The toxicity enhanced with increasing aqueous extract concentrations. The compounds isolated can interfere with seed germination and seedling growth of plants. Consequently, the study of these chemical interactions might be useful to develop new classes of environmentally safe herbicides. Fil: Scrivanti, Lidia Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Anton, Ana Maria Ramona. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

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 intraespecíicas 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 signiicativas (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 genus Celtis (Celtidaceae) comprises around 70 temperate to tropical woody taxa . In Argentina there appear four species, all of them belonging in the subgenus Mertensia Planch., whose inter and intraspeciic morphological variability and similarity has generated widespread taxonomic confusions. One of the most emblematic cases is that of C. ehrenbergiana (Klotzsch) Liebm., considered a very ample taxon encompassing both C. pallida Torr. and C. tala Gillies ex Planch. Given that both latter entities are clearly distinguishable in the ield, a morphological and taxonomic revision was performed. After extensive sampling, a detailed morphological study and through a Principal Components and Conglomerates Analysis, it was concluded that what is considered as C. ehrenbergiana in Argentina, actually involves three entities: C. tala, C. pallida var. pallida and C. pallida var. discolor Hunz. & Dottori, and the rehabilitation of those taxa is proposed. The Variance and Similarity Analysis results support signiicant differences (p-value < 0.05) between groups. The following relevant taxonomical characters were established: habit of the individual, bark pattern, pubescence of leaf blades, nerves and petioles, stipular spines/spiny branches, domacia aspect and abundance. Besides, some C. pallida specimens are morphologically intermediate between both varieties, and therefore their proper identity will be clariied through the use of molecular tools. Fil: Asmus, Jorgelina Pamela. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Botánica Morfológica y Sistemática Agronómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina Fil: Chamorro, Débora Cintia. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Botánica Morfológica y Sistemática Agronómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina Fil: Mogni, Virginia Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Botánica Morfológica y Sistemática Agronómica; Argentina Fil: Oakley, Luis Jorge. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Botánica Morfológica y Sistemática Agronómica; Argentina Fil: Prado, Darien Eros. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Biología. Cátedra de Botánica Morfológica y Sistemática Agronómica; Argentina

During the preparation of the treatment of the genus Plantago L. for the Flora Argentina project, dozens of names were identified as needing typification to stabilize their nomenclature. As a result, lectotypes are designated for 40 names, second-step lectotypes for four names, and a neotype for P. grandiflora Meyen. Furthermore, erroneous applications in past literature of the term "holotype" are corrected to lectotypes for five names. Fil: Moroni, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Hassemer, Gustavo. Universidad de Copenhagen; Dinamarca Fil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

Paspalum is a noteworthy grass genus due to the forage quality of most species, the total number of approximately 330 species, and the high proportion of those that reproduce via apomixis. Harnessing apomictic reproduction and widening the knowledge about the cytogenetic relationships among species are elemental tools for plant breeding.We conducted cytogenetic analyses of inter‐ and intraspecific hybridizations involving a sexual, colchicine‐induced autotetraploid plant of P.plicatulum Michx. and five indigenous apomictic tetraploid (2n = 40) species: P. compressifolium Swallen, P. lenticulare Kunth, two accessions of P. nicorae Parodi, P. rojasii Hack., and two accessions of P. plicatulum. The fertility of the hybrids was investigated and their reproductive system was analyzed considering the relative embryo:endosperm DNA content by flow cytometry. Morphological, nomenclatural and taxonomic issues were also analyzed.Cytogenetic analysis suggested that all indigenous tetraploid accessions of five apomictic species are autotetraploid or segmental allotetraploid. If segmental allotetraploids, they probably originated by autoploidy followed by diploidization processes. Autosyndetic male‐chromosome pairing observed in all hybrid families supported this assertion. Allosyndetic chromosome associations were also observed in all hybrid families. In the hybrids, the proportion of male‐parent chromosomes involved in allosyndesis per pollen mother cell varied from 5.5 to 35% and the maximum ranged between 25‐60%. The apomictic condition of the indigenous male parents segregated in the hybrids.These results confirm a strong association between autoploidy and apomixis in Paspalum, and the existence of cytogenetic relationships between different species of the Plicatula group. Allosyndetic chromosome pairing and seed fertility of the hybrids suggest the feasibility of gene transfer among species. Fil: Novo, Patricia Elda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Galdeano, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Espinoza, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Quarin, Camilo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Oxalis section Alpinae grows along the Andes, from Ecuador to the austral part of the South American continent. Across the section, leaves are always trifoliolate, but leaflets exhibit wide diversity in shape and size and have often been used as a diagnostic character. This study provides a comprehensive morphometric and phylogenetic framework of Oxalis sect. Alpinae. Thus, the shapes of 312 leaflets representing 14 species of O. sect. Alpinae are examined and elliptic Fourier analysis is used, which is a morphometric approach for the comparison of outlines in order to recognize patterns in shape evolution and to assess if the leaflets are an accurate diagnostic character at the species level. Moreover, a new molecular phylogenetic reconstruction is provided, and it is compared with the morphological space. The leaflet shape diversity cannot be fully explained by phylogenetic relations among species. However, different patterns of shape evolution can be distinguished, and there might be a spectrum from evolutionary lability to the conservatism of shape. Fil: Morello, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Sassone, Agostina Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: López, Alicia. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina

Heavy metal (HM) pollution of soils is one of the most important and unsolved environmental problems affecting the world, with alternative solutions currently being investigated through different approaches. Arbuscular mycorrhizal fungi (AMF) are soil inhabitants that form symbiotic relationships with plants. This alleviates HM toxicity in the host plant, thereby enhancing tolerance. However, the few investigations that have addressed the presence of metals in the fungus structures were performed under experimental conditions, with there being no results reported for Pb. The current study represents a first approximation concerning the capability of spores to accumulate Pb in the AMF community present in a Pb polluted soil under field conditions. Micro X-ray fluorescence was utilized to obtain a direct observation of Pb in spores, and the innovation of total reflection X-ray fluorescence was applied to obtain Pb quantification in spores. The AMF community included species of Ambisporaceae, Archaeosporaceae, Gigasporacea, Glomeraceae and Paraglomeraceae, and was tolerant to high Pb concentrations in soil. Pb accumulation in AMF spores was demonstrated at the community level and corroborated by direct observation of the most abundant spores, which belonged to the Gigasporaceae group. Spore Pb accumulation is possibly dependent on the AMF and host plant species. Fil: Salazar, María Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Menoyo, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Faggioli, Valeria. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Marcos Juárez; Argentina Fil: Geml, József. Naturalis Biodiversity Center. Biodiversity Dynamics Research Group; Países Bajos Fil: Cabello, Marta Noemí. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; Argentina Fil: Rodriguez, Judith Hebelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Marro, Nicolás Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Pardo, Alejandro Guillermo. Universidad Nacional de Quilmes; Argentina Fil: Pignata, Maria Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Becerra, Alejandra Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

A new podocarpaceous conifer is described from the early Danian Salamanca Formation (southern Chubut, Patagonia, Argentina) based on compressions of leafy branches with cuticular remains. Kirketapel salamanquensis gen. et sp. nov. has amphistomatic, scale-like leaves with marginal frills distinguishable at the apex; stomata oriented randomly in relation to the major axis of the leaf with four to five subsidiary cells and extremely reduced Florin rings; and irregularly shaped epidermal cells. We compare K. salamanquensis with extant and extinct members of the imbricate-leaved podocarps, among which it closely resembles Florin’s Dacrydium group C genera (i.e., Lagarostrobos, Manoao, Lepidothamnus and Halocarpus). Among these genera, only Lepidothamnus has a living representative in South America, the Chilean L. fonkii, whose leaf macro- and micromorphological characters are described in detail for comparison. Overall, the Patagonian fossil species is most similar to the extant and extinct members of Lagarostrobos in its cuticular micromorphology; however, macromorphological characters, such as the leaf size, apex curvature and mode of flattening, clearly differentiate it from all four genera of Dacrydium group C. We include Kirketapel salamanquensis in a combined molecular and morphological phylogenetic analysis conducted under the maximum parsimony criterion. The new, early Paleocene fossil taxon is confidently recovered as part of the scale-leaved clade as defined herein, which also includes Halocarpus, Phyllocladus, Lepidothamnus, Parasitaxus, Lagarostrobos and Manoao, and it constitutes the oldest record known for the group by at least 17 million years as well as its first fossil occurrence outside Australasia, establishing a widespread Gondwanan history. Furthermore, based on its oldest locality of occurrence, K. salamanquensis shows that the divergence of the total group of the scale-leaved podocarps occurred by at least 65 million years ago, adding to the growing systematic knowledge of earliest Cenozoic macrofloras in the Southern Hemisphere. Fil: Andruchow Colombo, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Escapa, Ignacio Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Carpenter, Raymond J.. University of Tasmania; Australia Fil: Hill, Robert S.. University of Adelaide; Australia Fil: Iglesias, Ari. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Abarzua, Ana M.. Universidad Austral de Chile; Chile Fil: Wilf, Peter. State University of Pennsylvania; Estados Unidos

The genus Machaerophorus includes three perennial species (M. arequipa, M. laticarpus, and M. matthioloides) inhabiting the southern Peruvian Andes. However, based on the morphological data, this genus has been reduced for more than one hundred years to synonymy of several genera of various tribes, and its phylogenetic placement using molecular data has never been studied. Therefore, in this study we explored the phylogenetic placement of Machaerophorus to test its generic status and tribal assignment, using for this purpose ribosomal nuclear (ITS) and chloroplast (trnL-F, trnH-psbA, rps16 intron) data together with a comprehensive sampling of taxa. Results obtained here demonstrated that Machaerophorus represents a well-differentiated lineage within the South American Cremolobeae–Eudemeae–Schizopetaleae clade, and hence, the genus is reinstated and excluded from the placements in Sibara and Mathewsia. Based on molecular data and morphological affinities, we included it within the tribe Schizopetaleae. A key to Machaerophorus and the genera of Schizopetaleae is also presented. Fil: Salariato, Diego Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Cueva Manchego, Marco A.. Universidad Nacional Mayor de San Marcos; Perú Fil: Cano, Asunción. Universidad Nacional Mayor de San Marcos; Perú Fil: Al-Shehbaz, Ihsan. Missouri Botanical Garden; Estados Unidos

After gene duplication, paralogous genes evolve independently, and consequently, the new proteins encoded by these duplicated genes are exposed to changes in their subcellular location. Although there are increasing evidence that phylogenetically related proteins play different functions in different subcellular compartments, the number of evolutionary steps required for the emergence of a novel protein with a novel subcellular localization remains unclear. Regarding this intriguing topic, here we examine in depth our previous reports describing both intracellular and extracellular polyhydroxybutyrate polymerases (PhaC) in the Pseudomonadales group. The recapitulation of the intracellular-to-extracellular localization switch of PhaC in these strains shows a gradual evolution from a simple cytosolic PhaC form to a complex extracellular PhaC form specifically secreted via the type 1 secretion system. This gradual evolution includes several adaptive and pre-adaptive changes at the genomic, genetic and enzymatic levels, which are intimately related to the lifestyle of organisms during the evolution of protein localization. We conclude that the protein localization switch can be an extremely complex process in nature. Fil: Stritzler, Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Jozefkowicz, Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina Fil: Soto, Gabriela Cynthia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina Fil: Ayub, Nicolás Daniel. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Specific leaf area (SLA) is a key trait to screen plants for ecological performance and productivity; however, the relationship between SLA and photosynthesis is not always up-scalable to growth when comparing multiple species with different life cycles. We explored leaf anatomy in annual and perennial species of Physaria, and related it to photosynthesis and water loss. The annual Physaria gracilis had higher SLA, thinner leaves, and lower investment in protective tissues, than perennial P. mendocina. Physaria angustifolia (annual), and P. pinetorum (perennial) showed intermediate values. Both perennials had a thicker palisade and high photosynthesis, relative to annuals. The larger leaf veins of perennials should allow high water availability to the mesophyll. The thicker palisade should determine high resistance to water flow and help explain their high water-use efficiency. These leaf functions reflect the construction of long-lived leaves that efficiently use resources under environmental limitations of arid environments. Fil: González Paleo, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Ravetta, Damián Andrés. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Fine root growth in natural vegetation is difficult to predict due to its regulation by soil and plant factors. Field studies in arid ecosystems show a variety of root responses to soil resources and to plant aboveground phenology that sometimes differ from root responses predicted by controlled experiments. There is a pressing need to cover a greater diversity of plant species and ecological scenarios in field studies. In this paper, we have studied fine roots of Prosopis flexuosa trees living with or without access to phreatic water in an inter-dune valley and a dune flank, respectively, in the Central Monte Desert, Argentina. We have described fine root growth over time and at different depths by rhizotron observations and soil core auger samples in relation to soil water and nutrients, tree crown phenology, plant water and nutrient status. We have found that surface soil moisture from rainfall is the variable that best predicts seasonal topsoil fine root growth. Access to groundwater advanced leaf sprouting with respect to rainfall, but did not advance root growth that stayed linked to rainfall in valley and dune flank trees. Trees without access to phreatic water produced deeper and thicker or denser roots, which is consistent with the poor soil resource content of dunes. Variations in rainfall dynamics due to global climate change may have a particular impact on fine roots and ecosystem processes such as biogeochemistry and carbon budget in dune flank trees as well as in valley trees. Fil: Guevara, Aranzazú. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Pancotto, Veronica Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Mastrantonio, Leandro Eloy. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina Fil: Giordano, Carla Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina

Diploneis Ehrenberg ex Cleve is a diverse genus, with species predominantly from epipelic, marine habitats; there are a few freshwater representatives. In 1933 Frenguelli reported four taxa of this genus at the Esteros del Iberá, a vast subtropical wetland from Argentina. Two of the four taxa reported were new for science. One of the reported species was Diploneis elliptica (Kützing) Cleve (Basionym: Navicula elliptica Kützing) a species cited from very diverse environments of every continent. In this study the type material of Navicula elliptica Kützing, deposited at the Natural History Museum in London, was analyzed with scanning electron microscopy and its valve fi ne structure described. Comparison of this type material with others studied under SEM from America, Europe, Africa and Asia indicate that D. elliptica has been widely misidentifi ed. The materials from Iberá, Argentina, deposited under this name in the Frenguelli´s Collection at the Museo de Ciencias Naturales de La Plata, belong to a new species, described here as Diploneis sudamericana. These two taxa are very similar when analyzed with LM but clearly diff er in the striae and areolae structure. D. sudamericana has uniseriate striae at valve center and biseriate near the valve margin; the alveoli are externally occluded by a unique complex cribrate occlusion. This species also diff ers from others in the areolae of the longitudinal canals and the external proximal raphe ends. Fil: Sala, Silvia Estela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; Argentina Fil: Vouilloud, Amelia Alejandra Beatriz. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; Argentina Fil: Heguilor, Santiago. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Química Ambiental y Biogeoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

Antecedentes y Objetivos: Los Hongos Micorrícicos Arbusculares (HMA) se encuentran asociados, en la naturaleza, con varias especies de antocerotes (Anthocerotophyta). El objetivo de este estudio es dar a conocer y caracterizar por primera vez la colonización de HMA en Nothoceros fuegiensis (Dendrocerotaceae). Métodos: El material examinado proviene de recolectas realizadas en bosques templados fríos dominados por Nothofagus spp. Las plantas fueron acondicionadas, teñidas y analizadas de acuerdo con técnicas específicas para briofitas. Resultados clave: Se describe por primera vez la asociación micorrícica en N. fuegiensis. Se presenta una descripción breve e ilustración de la planta y de las estructuras características del hongo micorrícico. El porcentaje de colonización es de 9-40%, ocasionalmente ausente, y su tipo morfológico es Paris. Conclusiones: Al describir la asociación entre HMA y un antocerote, N. fuegiensis, se aporta nueva información sobre los registros de asociaciones presentes en diferentes briofitas en ambientes poco conocidos o inexplorados. Background and Aims: Arbuscular Mycorrhizal Fungi (AMF) are associated, in nature, with several species of hornworts (Anthocerotophyta). The aim of this study is to describe and characterize for the first time AMF colonization in Nothoceros fuegiensis (Dendrocerotaceae). Methods: The material examined was collected in cold temperate forest dominated by Nothofagus spp. The plants were conditioned, stained and analyzed according to specific techniques for bryophytes. Key results: The mycorrhizal association in N. fuegiensis is described for the first time. A brief description and illustration of the plant and the characteristic structures of the mycorrhizal fungus are presented. The percentage of colonization ranges from 9-40%, occasionally absent and its morphological type is Paris. Conclusions: The association between AMF and a hornwort, N. fuegiensis, is described, thus providing new information on the records of this type of association present in different bryophyte taxa in little-known or unexplored environments. Fil: Cottet, Agustina Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Messuti, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Se registra por primera vez para la flora Argentina el helecho Actinostachys pennula (Schizaeaceae), sobre la base de material recién recolectado en el nordeste de la provincia de Misiones. Se incluye una descripción de la especie, observaciones ecológicas, e ilustraciones del esporofito y esporas características de la especie. First record of the genus Actinostachys (Schizaeaceae) for Argentina. The fern Actinostachys pennula (Schizaeaceae) is cited for the first time from Argentina, on the basis of material recently collected in the northeast of Misiones province. It is provided a description of the species, ecological observations, and illustrations of sporophyte and spores. Fil: Marquez, Gonzalo Javier. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Palinología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Keller, Hector Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Se cita por primera vez para el nordeste de la Argentina a Habenaria johannensis y H. josephensis, especies conocidas hasta el momento con el límite de distribución más austral en el sur del Brasil. Se aportan una breve descripción de las especies, distribución geográfica, observaciones ecológicas, fotografías de campo, un mapa con la distribución de los dos nuevos registros en la Argentina, así como también, una clave para diferenciar las especies de Habenaria presentes en el nordeste argentino., Two new records of Habenaria (Orchidaceae) for the Argentinian flora. Habenaria johannensis and H. josephensis, species known up to now with the distribution limit in southern Brazil, are cited for the first time for northeastern Argentina. A brief description of the species, geographical distribution, ecological observations, field photographs, a map with the distribution of the two new records in Argentina, as well as a key to differentiate the species present in northeastern of Argentina are provided., Instituto de Limnología "Dr. Raúl A. Ringuelet"

The number of host species infected by a mistletoe (host range) is critical in that it influences prevalence, virulence and overall distribution of the parasite; however, macroecological analyses of this life history feature are lacking for many regions. The Andean-Patagonian forest, found along the southern Andes from 35 °S to Tierra del Fuego at 55 °S, contains 12 mistletoe species in three families (Loranthaceae, Misodendraceae and Santalaceae). By tabulating herbarium records, the host ranges and geographical distributions of these mistletoes were explored. Our results show that these parasites occur on 43 plant species in 24 families but with varying degrees of specificity. All Misodendrum species and Desmaria mutabilis (Loranthaceae) are specialists that use Nothofagus as their primary hosts. Tristerix and Notanthera (Loranthaceae) and Antidaphne and Lepidoceras (Santalaceae) are generalists parasitizing more than six host species from several genera and families. Although many of the mistletoe species are sympatric, there is low overlap in host use. Our data show that in the southern South American bioregion, generalist mistletoes have smaller geographic ranges than specialists. This contrast with a previous hypothesis that predicted mistletoes with large geographic ranges would also have large host ranges, and conversely, less diverse regions would have more specialised mistletoes. Fil: Amico, Guillermo Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Nickrent, Daniel. Southern Illinois University; Estados Unidos Fil: Vidal Russell, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Animal-pollinated flowers may orient resources for competing activities, such as nectar production for attracting flower visitors but then saving nectar (through inhibiting nectar production or by final resorption) for the subsequent maturation of fruits and seeds. Nectar production is continuous in Nicotiana longiflora and N. alata after flower opening, but early nectar removal reduces total secreted nectar. Resource trade-off between nectar investment and seed production were experimentally assessed in manually pollinated flowers experiencing different numbers of repeated nectar removals, while controlling for maternal effects. We expected that flowers with less nectar secretion produce larger seed sets. The results showed that for both species the earlier the nectar removal during flower anthesis, the lower the total nectar secreted and the higher the mass of seeds produced. This general pattern was clearer for N. longiflora. The link between decreased nectar production and the subsequent increase in the seed set implies that resources are limited. Consequently, nectar savings during the pollination process through early nectar removal by pollinators can be interpreted as a trade-off between resources secreted by flowers for pollinator attraction and those utilized during fruit and seed maturation. Fil: Galetto, Leonardo. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Araujo, Francielle Paulina. Universidade Estadual do Rio Grande do Sul; Brasil Fil: Grilli, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Amarilla, Leonardo. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Torres, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Sazima, Marlies. Universidade Estadual de Campinas; Brasil

Paspalum stellatum is widely distributed in the American continent and it is known to include diploid cytotypes (2n = 2x = 20) and polyploid cytotypes (2n = 32 and 52). It is closely related to P. eucomum, P. malmeanum and P. schesslii. After chromosome counting and geographical mapping of the different cytotypes, phylogenetic relationships between them were explored in order to infer the origin and evolution of the polyploid complex P. stellatum and related species. Additionally, several unusual chromosome numbers are here reported for P. stellatum (2n = 30, 46, 48, 56 and 60) from the Brazilian cerrado. Phylogenetic analysis using plastid DNA showed that the cytotypes of P. stellatum split into two clades, one of which included all accessions with 2n = 32 and P. schesslii. Using ITS for phylogenetic analysis showed that P. schesslii, P. malmeanum and P. eucomum were grouped together as expected. The origin of the cytotype 2n = 32 of P. stellatum may have involved P. schesslii as one of the putative progenitors with a diploid cytotype of P. stellatum as the other. Fil: Bonasora, Marisa Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: López, Alicia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vaio, Magdalena. Universidad de la República; Uruguay Fil: Speranza, Pablo R.. Universidad de la República; Uruguay Fil: Honfi, Ana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentina Fil: Rua, Gabriel Hugo. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Spores of species of Sphaeropteris genus from America were studied with TEM and SEM. Six species were quoted as growing in America (cf. Tryon, 1971; Windisch, 1977): Sphaeropteris brunei (Christ) Tryon, Sphaeropteris cuatrecasacansii Tryon, Sphaeropteris gardneri (Hook.) Tryon, Sphaeropteris horrida (Liebm.) Tryon, Sphaeropteris insignis (D. C. Eaton) Tryon and Sphaeropteris quindiuensis (Karst.) Tryon. The aims are to characterize the species through their spore morphology and sporoderm ultrastructure. Based on these results it speculates about the relationships of these taxa within the family Cyatheaceae. It was find out with SEM, three kinds of surfaces can be recognized. It was find out with TEM that the exospore and perispore have two layers. The perispore is composed of an inner layer with three strata and the outer layer has two strata. The palynological characteristics were important in the identification of a natural taxonomic group. Fil: Marquez, Gonzalo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Palinología; Argentina

Capsicum comprises 35 species of chili peppers and five of them are cultivated worldwide as spices or vegetables. Diploid karyotypes based in x = 12 and x = 13 are common in Capsicum and the constitutive heterochromatin (cHet) is of particular interest in the genus since it is largely variable, particularly its highly GC-rich fraction. However, the repetitive DNA components of this heterochromatic regions are unknown. Given the co-localization of rDNA loci with the CMA+DAPI– heterochromatic bands, we tested the hypothesis that the highly GC-rich cHet fraction is composed of the whole 18S-25S ribosomal DNA (rDNA) unit or some of its components. Here we report on a novel satellite for Capsicum and Solanaceae composed of the complete rDNA unit. We physically mapped six Capsicum derived specific 18S-25S rDNA probes that covered the entire span of the rDNA unit and analysed a DraI restriction product on eight chromosomally different taxa of Capsicum, representative of the major phylogenetic clades of chili peppers. The co-localization of every gene and spacer probes of the 18S-25S rDNA unit suggest their structural function as a major repetitive component of the highly GC-rich cHet in Capsicum species with x = 12. In addition, analyses of the clones derived from restriction assays in C. pubescens suggested that the differential functional status of 18S-25S rDNA loci (nucleolar organizer regions -NORs- or cHet) in this species is related to a divergence in a short sequence upstream the regulatory transcription initiation site (TIS) of the intergenic spacer (IGS). The results here provided evidence that an rDNA mega satellite played a significant role in the evolution of the karyotype features of x = 12 Capsicum species. The finding of a mega satellite family derived from the whole rDNA unit is a novelty for plant genomes. Fil: Grabiele, Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; Argentina Fil: Debat, Humberto Julio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Scaldaferro, Marisel Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Aguilera, Patricia Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; Argentina Fil: Moscone, Eduardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Seijo, José Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Ducasse, Daniel Adrián. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina

Citharexylum es un género americano de arbustos y árboles, con unas 130 especies. Para la Argentina habían sido citadas cuatro especies. En el presente trabajo, una quinta especie, C. solanaceum, hasta ahora sólo conocida para el sur de Brasil, es citada por primera vez para la provincia de Misiones. Se proporciona una descripción de la especie, junto con ilustraciones, fotos, mapa de distribución y una clave para las especies de Citharexylum que crecen en la Argentina Citharexylum is an American genus of shrubs and trees, with about 130 species. Four species were formerly cited for Argentina. In the present work a fifth species, C. solanaceum, up till now only known from southern Brazil, is reported for the first time for the province of Misiones. A description of the species, together with illustrations, photos, a distribution map, and a key to the species of Citharexylum in Argentina are here provided. Fil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Keller, Hector Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Lepidaploa is a taxonomically complex genus of Vernonieae, which is difficult to delimit morphologically due to vegetative and reproductive characters that overlap with Chrysolaena and Lessingianthus. Anatomical studies of cypselae are taxonomically useful for delimiting subtribes, genera and species of Asteraceae, and especially within Astereae and Eupatorieae. Given the importance of cypselae to the taxonomy of tribes of Asteraceae, we searched for morphological patterns among the species of Lepidaploa. Using light microscopy, we analyzed fruits of 21 species of Lepidaploa to evaluate the taxonomic position of the genus and species of questionable placement in the group. Our results showed that the morphologies of the cypselae of species of Lepidaploa are homogeneous and similar to other species of Vernonieae. However, pappus vascularization and the number of mesocarp layers could be useful for differentiating the sister groups Chrysolaena, Lepidaploa and Lessingianthus, which present similar macro-and micro-morphological, palynological and chromosomal characters. Also, the presence of glandular trichomes and idioblasts in the cypsela, and lignified cells in the carpopodium exocarp, can be used to separate closely related species. Fil: Marques, Danilo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Oliveira Franca, Rafael de. Universidade Estadual de Maringá; Brasil Fil: Dematteis, Massimiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Marzinek, Juliana. Universidade Federal de Uberlândia; Brasil

Micromorphological and palynological characters of all Stenocephalum Sch.Bip. species (Vernonieae, Asteraceae) were analyzed to evaluate their reliability as taxonomic markers at generic level and discussed in relation to other genera of the subtribe Lepidaploinae. Characters such as pubescence of corollas and cypselae showed glandular and nonglandular trichomes allowing differentiation among related species. Apical appendages without glandular trichomes, caudate anthers, and carpopodium structure are common characteristics among Stenocephalum species. With the exceptions of S. megapotamicum and S. tragiaefolium, almost all species of the genus showed style bases without basal nodes for the first time. Crystals on the fruits wall were also observed for the first time in almost all the Stenocephalum species, with the exception of S. hystrix. However, the crystals would not constitute diagnostic features, since they vary widely among species. All the species showed type C pollen and the genus is considered stenopalynous. However, highly significant differences in palynological features among the species of the genus were observed. The different combinations of the micromorphological and palynological features of Stenocephalum here analyzed are valuable within genera to differentiate related species from one another. The value of all these characters could be increased if they are combined with other morphological or traditional data. Fil: Angulo, Maria Betiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Chalup, Laura María Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Dematteis, Massimiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Opuntia is the most diverse and widespread genus in the cactus family. In spite of the strong relationship with biotic pollination, little is known about their floral nectaries. We present the first deep structural and ultrastructural description of the floral nectaries of two Opuntia species (Opuntia anacantha var. retrorsa; Opuntia elata var. elata), linking these attributes to their functioning. A characterization of their floral visitors is also made. Both nectaries are very similar and represent the hypanthial type, with the presence of surface undulations that favor nectar retention. In O. elata, the style dilatation forms a nectar chamber. Three tissues are distinguished in these nectaries: an epidermis consisting of a single layer of cells with a thin cuticle, a nectariferous parenchyma with numerous vascular bundles with xylem and phloem and, a subnectariferous parenchyma with numerous amyloplasts. Pre-nectar may come from the starch hydrolysis of these plastids as well as from other green tissues of the plant. The exudation occurs through stomata and cuticle microchannels. O. anacantha may be a melittophilous plant, while in O. elata the presence of a nectar chamber and the orange color of the perianth suggest an incipient ornithophily. Fil: Agüero, Juan Ignacio. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentina Fil: Galati, Beatriz Gloria. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; Argentina Fil: Torretta, Juan Pablo. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentina

We studied the resistance of Parmotrema austrosinense to UV-B stress. We focused on the effects of a high dose UV-B radiation on the content of chlorophylls, carotenoids and UV-B screening compounds. Photosynthetic parameters were measured by chlorophyll fluorescence (potential and effective quantum yields, photochemical and non-photochemical quenching) and evaluated in control and UV-B-treated lichens. Lichens from two different locations in Cordoba, Argentina, were selected: (i) high altitude and dry plots at (Los Gigantes) and (ii) lowland high salinity plots (Salinas Grandes). UV-B treatment led to a decrease in the content of photosynthetic pigments and UV-B screens (absorbance decrease in 220–350 nm) in the samples from Salinas Grandes, while in Los Gigantes samples, an increase in UV-B screen content was observed. Chlorophyll fluorescence parameters showed a UV-B-induced decline in FV/FM, ΦPSII and qP indicating limitation of primary photosynthetic processes in photosystem II (PSII) of symbiotic alga, more pronounced in Salinas Grandes samples. Protective mechanism of PSII were activated by the UV-B treatment to a higher extent in samples from Salinas Grandes (NPQ 0.48) than in Los Gigantes samples (NPQ 0.26). We concluded that site-related characteristics, and in particular different UV-B radiation regimen, had a strong effect on resistance of the photosynthetic apparatus of P. austrosinense to UV-B radiation. Fil: Barták, M.. Masaryk University; República Checa Fil: Pláteníková, E.. Masaryk University; República Checa Fil: Carreras, Hebe Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Hájek, J.. Masaryk University. Faculty Of Sciences; República Checa Fil: Morkusová, J.. Masaryk University. Faculty Of Sciences; República Checa Fil: Mateos, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Marecková, M.. Masaryk University. Faculty Of Sciences; República Checa

Since their discovery, twenty years ago, KT-HAK-KUP transporters have become a keystone to understand how alkali cation fluxes are controlled in major land-dwelling photosynthetic organisms. In this review we focus on their discovery, phylogeny, and functions, as well as the regulation of its canonical member, AtHAK5. We also address issues related to structure-function studies, and the technological possibilities opened up by recent findings. Available evidence suggests that this family of transporters underwent an early divergence into major groups following the conquest of land by embryophytes. KT-HAK-KUPs are necessary to accomplish several major developmental and growth processes, as well as to ensure plant responses to environmental injuries. Although the primary function of these transporters is to mediate potassium (K+) fluxes, some of them can also mediate sodium (Na+) and cesium (Cs+) transport, and contribute to maintenance of K+ (and Na+) homeostasis in different plant tissues. In addition, there is evidence for a role of some members of this family in auxin movement and in adenylate cyclase activity. Recent research, focusing on the regulation of the canonical member of this family, AtHAK5, revealed the existence of a complex network that involves transcriptional and post-transcriptional phenomena which control the enhancement of AtHAK5-mediated K+ uptake when Arabidopsis thaliana plants are faced with low K+ supply. In spite of the formidable advances made since their discovery, important subjects remain to be elucidated to gain a more complete knowledge of the roles and regulation of KT-HAK-KUPs, as well as to improve their use for innovative procedures in crop breeding. Fil: Santa Maria, Guillermo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina. Universidad Nacional de San Martín; Argentina Fil: Oliferuk, Sonia. Universidad Nacional de San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Moriconi, Jorge Ignacio. Universidad Nacional de San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina

Two new species of Psyllocarpus sect. Psyllocarpus are here described and illustrated. Psyllocarpus bahiensis and Psyllocarpus scatignae, from the campo rupestre s. l. of Bahia and Minas Gerais states, respectively. We provide comments on their distribution, habitat, conservation status, and taxonomy. In addition, we analysed floral, fruit, and seed micromorphology, aswell as pollen grains of the new species. We also provide an updated identification key to the species of P. sect. Psyllocarpus. Fil: Martins Do Carmo, Joao Afonso. Universidade Estadual Do Campinas. Instituto de Biología. Departamento de Botanica; Brasil Fil: Sobrado, Sandra Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Salas, Roberto Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Olmos Simões, André. Universidade Estadual Do Campinas. Instituto de Biología. Departamento de Botanica; Brasil

Brazil is a mega diverse country, but as consequence of habitat degradation several plant species are threatened. Quillaja brasiliensis is a rare and threatened tree species of the temperate forests of South America. We investigated protocols for germination, seedling growth and transplantation. We discuss some ecological matters that could affect the species’ establishment. We evaluated germination under a range of storage periods, temperature and light conditions, the effects of transplantation and the development of seedlings under two sowing methods. We found that seeds germinated rapidly and have a high germination rate. Temperature influenced germination vigour, and photoperiod infl uenced synchrony. There was increased and faster germination under controlled culture conditions. The high germination rate and rapid growth qualify Q. brasiliensis as a potential species for restoring degraded areas and enrichment programmes. Fil: Velazco, Santiago José Elías. Universidade Federal do Paraná; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; Argentina Fil: Blum, Christopher Thomas. Universidade Federal do Paraná; Brasil Fil: Hoffmann, Pablo Melo. Sociedade Chauá; Brasil

Key message: Intra-individual variations of plant responses to environmental conditions are related to axis differentiation. Plastic responses include variations in primary growth, shoot allometry, leaves’ chlorophyll content and water use efficiency. Abstract: Primary growth affects plant plasticity by influencing the number, spatial arrangement and time of differentiation of the leaves. For Nothofagus obliqua, we evaluated if primary shoot growth dynamics determines short-term responses to environmental conditions, and intra-individual variations in such responses. Before bud-break, saplings were located in experimental conditions, combining two light treatments with two water supply treatments. For each individual, morphology, relative extension rate (RER), and relative leaf chlorophyll content (SPAD units) were registered for the annual shoot derived from the most distal bud of two axis categories: the main axis (trunk) and a main branch. For trunk shoots, we analysed the net photosynthetic rate at saturating photosynthetic photon flux density (Psat) of proximal and distal leaves. Shaded trees had higher RER, longer and more slender shoots, longer internodes, and higher leaf chlorophyll content than unshaded trees. The number of nodes was affected by water condition in trunk shoots, and by light condition in main branch shoots. Full sunlight stimulated the development of a branch following the length and growth direction of its parent shoot (relay branch). Shade would have promoted the development of neoformed leaves. Under shade and low water availability, water use efficiency was higher in distal than proximal leaves. Under high sunlight and water availability, leaves of relay branches presented slightly higher Psat with higher water loss than both proximal preformed leaves and distal leaves under the other tested conditions. This study highlights the need of assessing intra-individual variations in shoot acclimation in relation to axis differentiation. Fil: Torres, Cristian Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Magnin, Noel Amaru. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Varela, Santiago Agustín. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Area de Recursos Naturales; Argentina Fil: Stecconi, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional de Río Negro; Argentina Fil: Grosfeld, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - Patagonia Norte. Unidad de Adm.territorial; Argentina. Universidad Nacional del Comahue; Argentina Fil: Puntieri, Javier Guido. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - Patagonia Norte. Unidad de Adm.territorial; Argentina

Plant domestication genetics has been of interest not only for evolutionary biologists but also for anthropologists and breeders, because of its past and present role in human cultural evolution. Capsicum baccatum, which grows in the Seasonally Dry Tropical Forests of South America (SDTF), was domesticated by native peoples and used as a spice. The centre of domestication has been discussed, and vast territories of Peru and Bolivia have been proposed. The aims of this research were to elucidate the geographical origin of cultivated C. baccatum and to infer geological and climate events that have influenced the distribution of its genetic variability. Samples were collected from 25 localities across the entire range of wild C. baccatum and analysed using DNA sequences and phylogeographical approaches; they were then compared with 20 samples of cultivated forms obtained from different South American markets. We found a main centre of C. baccatum domestication spanning Bolivian Amazonia and the inter-Andean valleys. We also inferred an ancient cultivation site between Bolivia and Argentina. Finally, we found two lineages of wild populations distributed in nuclei of SDTFs which have been fragmented during glacial periods, when aridity increased and expansion of Chaco vegetation fragmented the region. Fil: Scaldaferro, Marisel Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Acosta, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

Cheilanthoid ferns (Cheilanthoideae sensu PPG 1 2016) constitute an important group within the Pteridaceae and are cosmopolitan in distribution. In South America, there are 155 species distributed in 13 genera, among which the largest are Adiantopsis (35), Cheilanthes (27), and Doryopteris (22). Most of the cheilanthoid species are morphologically adapted to grow in arid to semi-arid conditions and show convergent evolution, which has implied difficulties in defining the genera throughout their taxonomic history (Copeland 1947, Tryon & Tryon 1973, Gastony & Rollo 1995, 1998, Kirkpatrick Systematic Botany, 32: 504–518, 2007, Rothfels et al. Taxon, 57: 712–724, 2008). Here, we sequenced two plastid markers (rbcL + trnL-F) of 33 South American cheilanthoid species, most of which have not been included in phylogenetic analyses previously. The South American species were analyzed together with South African and Australasian Cheilanthes and representatives of related cheilanthoid genera. The phylogenetic analysis showed that most Cheilanthes species are related to the genus Hemionitis, constituting different groups according to their distribution; moreover, three species—C. hassleri, C. pantanalensis, and C. obducta—appear as the sister clade of Hemionitis. Cheilanthes micropteris, the type species, is strongly supported in a clade with Australasian Cheilanthes plus five South American Cheilanthes species, all of which show a reduction in the number of spores per sporangium; this feature would be a synapomorphy for core Cheilanthes s.s. We found no support uniting other South American Cheilanthes to either the group of South African Cheilanthes or to core Cheilanthes s.s. On the other hand, C. geraniifolia, C. goyazensis, and C. bradei formed a clade related to Doryopteris that, with further study, could be considered as a new genus. The phylogenetic hypotheses presented here contribute substantially to the delimitation of Cheilanthes s.s. and related groups and provide the basis for re-examining the generic taxonomy. Fil: Ponce, Marta Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Scataglini, María Amalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina