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Antarctic flowering plants have become enigmatic because of their unique capability to colonize Antarctica. It has been shown that there is not a single trait that makes Colobanthus quitensis and Deschampsia antarctica so special, but rather a set of morphophysiological traits that coordinately confer resistance to one of the harshest environments on the Earth. However, both their capacity to inhabit Antarctica and their uniqueness remain not fully explained from a biological point of view. These aspects have become more relevant due to the climatic changes already impacting Antarctica. This review aims to compile and update the recent advances in the ecophysiology of Antarctic vascular plants, deepen understanding of the mechanisms behind their notable resistance to abiotic stresses, and contribute to understanding their potential responses to environmental changes. The uniqueness of Antarctic plants has prompted research that emphasizes the role of leaf anatomical traits and cell wall properties in controlling water loss and CO2 exchange, the role of Rubisco kinetics traits in facilitating efficient carbon assimilation, and the relevance of metabolomic pathways in elucidating key processes such as gas exchange, nutrient uptake, and photoprotection. Climate change is anticipated to have significant and contrasting effects on the morphophysiological processes of Antarctic species. However, more studies in different locations outside Antarctica and using the latitudinal gradient as a natural laboratory to predict the effects of climate change are needed. Finally, we raise several questions that should be addressed, both to unravel the uniqueness of Antarctic vascular species and to understand their potential responses to climate change.

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While the importance of interdisciplinary approaches is increasingly recognised in conservation, bridging knowledge systems across scales remains a fundamental challenge. Focusing on the Important Plant Areas (IPA) approach, we evaluate how complementing scientific and local knowledge can better inform the conservation of useful plants in Colombia. We worked in three municipalities to investigate knowledge on useful plant richness, species composition and use types, as well as perceptions on area-based plant conservation approaches. Participatory focus groups and ethnobotanical walks-in-the-woods were undertaken with local communities, while scientific data were represented by occurrence records from global data aggregators and digitised collections. A total of 1190 species with human uses were reported. Combining knowledge systems provided the richest understanding of useful plants but the relative contribution of each system varied between study areas, influenced by the history of scientific studies, socio-ecological context and study design. Meanwhile, local perceptions of how conservation areas should be selected differed from global IPA criteria. These results show that working with local communities can improve biological understanding for spatial conservation planning. Additionally, participatory approaches must move beyond community-based conservation and data collection, to inform the design of global conservation programmes.

RESUMEN: Si bien la importancia de los enfoques interdisciplinarios se reconoce cada vez más en la conservación, articular los sistemas de conocimiento a través de sus escalas sigue siendo un desafío fundamental. Centrándonos en el enfoque de Áreas Importantes para Plantas (AIP), evaluamos cómo la integración entre conocimiento científico y local puede mejorar la información para la conservación de las plantas útiles en Colombia. Trabajamos en tres municipios para investigar el conocimiento sobre la riqueza de plantas útiles, la composición de especies y los tipos de uso, así como las percepciones sobre los enfoques de conservación de plantas basados en áreas. Se llevaron a cabo grupos de enfoque participativos y caminatas etnobotánicas en el bosque con las comunidades, mientras que los datos científicos se representaron mediante registros de ocurrencia de agregadores de datos globales y colecciones digitalizadas. En total se reportaron 1.190 especies con usos humanos. La combinación de sistemas de conocimiento proporcionó la comprensión más rica de las plantas útiles, pero la contribución relativa de cada sistema varió entre las áreas de estudio, influenciada por la historia de los estudios científicos, el contexto socioecológico y el diseño del estudio. Por otra parte, las percepciones locales sobre cómo se deben seleccionar las áreas de conservación difirieron de los criterios globales de las AIP. Estos resultados muestran que trabajar con las comunidades locales puede mejorar la comprensión biológica para la planificación de la conservación espacial. Además, los enfoques participativos deben ir más allá de la recopilación de datos y la conservación basada en la comunidad, para instruir el diseño de programas de conservación global.

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Abstract Despite an economy based mostly on agriculture, literature on viral diseases of plants is scarce in Paraguay. Only recently, researches on plant viruses took an impulse resulting in a precise identification of many of them affecting plants either cultivated or not. To provide reliable information regarding plant viruses present in Paraguay, an annotated list of them was prepared, covering descriptions from 1920 to present day. There have been some important outbreaks with severe yield losses in crops as cucurbits, citrus, sesame, bean, maize, peanuts and tomato. Many of older descriptions are included for their historical significance, but most identifications made require confirmation. On the other hand, recent descriptions have been completed, based on several assays, especially molecular characterization. This list is organized alphabetically following scientific names of the plant species found naturally infected by viruses, with comments about symptoms, geographical distribution, incidence, identification procedures, and other information, with due literature references. It is based on a compilation of publications made on plant virus diseases in Paraguay. Described virus species, in a total of 38 recognized by ICTV, belonging to 17 different genera (Alphaendornavirus, Ampelovirus, Begomovirus, Benyvirus, Carlavirus, Cilevirus, Closterovirus, Comovirus, Cucumovirus, Dichorhavirus, Fabavirus, Luteovirus, Ophiovirus, Orthotospovirus, Potexvirus, Potyvirus and Tobamovirus), besides two unclassified, and four unidentified. There is also a case of viroid described in Citrus spp. Infections caused by potyviruses are the most numerous. These viruses were described in more than 40 plant species, belonging to 18 botanical families. Because of crop diversity and richness in native flora, many more viruses must be present in Paraguay, which future works will certainly reveal, especially with the increase in manpower involving researches, especially cooperative with foreign centers, on plant viruses, which has been very limited until now. Also, knowledge on existing viruses may have relevance in understanding their epidemiology and provide the basis for their control strategies and quarantine measures, to avoid new variants of existing viruses or new viruses being introduced.

Resumo A pesar de una economía basada principalmente en la agricultura, la literatura sobre enfermedades virales de las plantas es escasa en Paraguay. Sólo recientemente se han impulsado las investigaciones sobre los virus de plantas, lo que ha permitido identificar con precisión muchos de ellos que afectan a plantas cultivadas o no. Para brindar información confiable sobre los virus de plantas presentes en el Paraguay, se elaboró una lista comentada de los mismos, abarcando descripciones desde 1920 hasta la actualidad. Se han producido algunos focos importantes con severas pérdidas de rendimiento en cultivos de cucurbitáceas, cítricos, sésamo, frijol, maíz, maní y tomate. Muchas de las descripciones más antiguas se incluyen por su importancia histórica, pero la mayoría de las identificaciones realizadas requieren confirmación. Por otro lado, las descripciones recientes han sido completadas, basadas en varios ensayos, especialmente de caracterización molecular. Esta lista está organizada alfabéticamente siguiendo los nombres científicos de las especies de plantas que se encontraron naturalmente infectadas por virus, con comentarios sobre síntomas, distribución geográfica, incidencia, procedimientos de identificación y otras informaciones, con las debidas referencias bibliográficas. Se basa en una recopilación de publicaciones realizadas sobre enfermedades virales de plantas en Paraguay. Especies de virus descritas, en un total de 38 reconocidas por el ICTV, pertenecientes a 17 géneros diferentes (Alphaendornavirus, Ampelovirus, Begomovirus, Benyvirus, Carlavirus, Cilevirus, Closterovirus, Comovirus, Cucumovirus, Dichorhavirus, Fabavirus, Luteovirus, Ophiovirus, Orthotospovirus, Potexvirus, Potyvirus y Tobamovirus), además de dos sin clasificar y cuatro sin identificar. También existe un caso de un viroide descrito en Citrus spp. Las infecciones causadas por potyvirus son las más numerosas. Estos virus fueron descritos en más de 40 especies de plantas, pertenecientes a 18 familias botánicas. Debido a la diversidad de cultivos y la riqueza de la flora nativa, muchos más virus deben estar presentes en Paraguay, lo que seguramente revelarán trabajos futuros, especialmente con el aumento de la mano de obra involucrada en investigaciones, en cooperación con centros extranjeros, sobre virus de plantas, que ha sido muy limitada hasta el momento. Además, el conocimiento sobre los virus existentes puede ser relevante para comprender su epidemiología y proporcionar una base para sus estrategias de control y medidas de cuarentena, para evitar la introducción de nuevas variantes de virus existentes o nuevos virus.

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The Costa Rican Paramo is a unique ecosystem with high levels of endemism that is geographically isolated from the Andean Paramos. Paramo ecosystems occur above Montane Forests, below the permanent snow level, and their vegetation differs notably from that of adjacent Montane Forests. We compared the composition and beta diversity of blooming plant species using phenological data from functional plant groups (i.e., insect-visited, bird-visited and insect + bird-visited plants) between a Paramo and a Montane Forest site in Costa Rica and analyzed seasonal changes in blooming plant diversity between the rainy and dry seasons. Species richness was higher in the Montane Forest for all plant categories, except for insect-visited plants, which was higher in the Paramo. Beta diversity and blooming plant composition differed between both ecosystems and seasons. Differences in species richness and beta diversity between Paramo and the adjacent Montane Forest are likely the result of dispersal events that occurred during the last glacial period and subsequent isolation, as climate turned to tropical conditions after the Pleistocene, and to stressful abiotic conditions in the Paramo ecosystem that limit species establishment. Differences in blooming plant composition between both ecosystems and seasons are likely attributed to differential effects of climatic cues triggering the flowering events in each ecosystem, but phylogenetic conservatism cannot be discarded. Analyses of species composition and richness based on flowering phenology data are useful to evaluate potential floral resources for floral visitors (insects and birds) and how these resources change spatially and temporarily in endangered ecosystems such as the Paramo.

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Natural regeneration of recalcitrant-seeded tree species is strongly limited in Mediterranean-type climate zones due to increasing droughts imposed by climate change. Direct seeding can be a low-cost alternative to seedling establishment, but there is still limited information for some species. This study aimed to assess the effects of the seed source and forest cover on the germination and survival of the endemic Cryptocarya alba Mol. established through direct seeding. Three habitat types differing in forest cover were identified within the natural park Reserva Natural Altos de Cantillana, Metropolitan Region, Chile. The forest cover corresponded to open (canopy density <25%), semi-dense (canopy density around 50%), and dense forest (canopy density >75%). All forest cover had C. alba as one of the dominant species. At each habitat type, 38 families from four seed sources (Cuesta La Dormida (CD), Antumapu (AN), Cantillana (CA, local seed source) and Cayumanque (CY)) were directly seeded. Germination (Germin) and survival (Surv) were evaluated weekly during one growing season. There were significant differences between seed sources in Germin and Surv, with means values varying from 7.8% to 37% for Germin and 0% to 20% for Surv. The local seed source CA had the highest values in both traits. A significant variation was also observed between families within seed sources only for Germin. The dense forest cover had the highest Germin (22%) and Surv (55%) results compared to the other forest cover types, which was partially associated with differences in soil moisture, temperature, and bulk density. Due to the most frequent droughts in these Mediterranean-type climate zones, the use of local seeds on dense forest cover is recommended for the direct seeding of the species in the initial recruitment.

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Projected rises in atmospheric CO2 concentration and minimum night-time temperatures may have important effects on plant carbon metabolism altering the carbon balance of the only two vascular plant species in the Antarctic Peninsula. We assessed the effect of nocturnal warming (8/5 °C vs. 8/8 °C day/night) and CO2 concentrations (400 ppm and 750 ppm) on gas exchange, non-structural carbohydrates, two respiratory-related enzymes, and mitochondrial size and number in two species of vascular plants. In Colobanthus quitensis, light-saturated photosynthesis measured at 400 ppm was reduced when plants were grown in the elevated CO2 or in the nocturnal warming treatments. Growth in elevated CO2 reduced stomatal conductance but nocturnal warming did not. The short-term sensitivity of respiration, relative protein abundance, and mitochondrial traits were not responsive to either treatment in this species. Moreover, some acclimation to nocturnal warming at ambient CO2 was observed. Altogether, these responses in C. quitensis led to an increase in the respiration-assimilation ratio in plants grown in elevated CO2. The response of Deschampsia antarctica to the experimental treatments was quite distinct. Photosynthesis was not affected by either treatment; however, respiration acclimated to temperature in the elevated CO2 treatment. The observed short-term changes in thermal sensitivity indicate type I acclimation of respiration. Growth in elevated CO2 and nocturnal warming resulted in a reduction in mitochondrial numbers and an increase in mitochondrial size in D. antarctica. Overall, our results suggest that with climate change D. antarctica could be more successful than C. quitensis, due to its ability to make metabolic adjustments to maintain its carbon balance.

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Crop and weed discrimination in natural field environments is still challenging for implementing automatic agricultural practices, such as weed control. Some weed control methods have been proposed. However, these methods are still restricted as they are implemented under controlled conditions. The development of a sound weed control system begins by recognizing the crop and the different weed plants presented in the field. In this work, a classification approach of Zea mays L. (Crop), narrow-leaf weeds (NLW), and broadleaf weeds (BLW) from multi-plant images are presented. Moreover, a large image dataset was generated. Images were captured in natural field conditions, in different locations, and growing stages of the plants. The extraction of regions of interest (ROI) is carried out employing connected component analysis (CCA), whereas the classification of ROIs is based on Convolutional Neural Networks (CNN) and compared with a shallow learning approach. To measure the classification performance of both methods, accuracy, precision, recall, and F1-score metrics were used. The best alternative for the weed classification task at early stages of growth and in natural corn field environments was the CNN-based approach, as indicated by the 97% accuracy value obtained.

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Essential oils (EOs) and their compounds have attracted particular attention for their reported beneficial properties, especially their antiviral potential. However, data regarding their anti-SARS-CoV-2 potential are scarce in the literature. Thus, this study aimed to identify the most promising EO compounds against SARS-CoV-2 based on their physicochemical, pharmacokinetic, and toxicity properties. A systematic literature search retrieved 1669 articles; 40 met the eligibility criteria, and 35 were eligible for analysis. These studies resulted in 465 EO compounds evaluated against 11 human and/or SARS-CoV-2 target proteins. Ninety-four EO compounds and seven reference drugs were clustered by the highest predicted binding affinity. Furthermore, 41 EO compounds showed suitable drug-likeness and bioactivity score indices (≥0.67). Among these EO compounds, 15 were considered the most promising against SARS-CoV-2 with the ADME/T index ranging from 0.86 to 0.81. Some plant species were identified as EO potential sources with anti-SARS-CoV-2 activity, such as Melissa officinalis Arcang, Zataria multiflora Boiss, Eugenia brasiliensis Cambess, Zingiber zerumbet Triboun & K.Larsen, Cedrus libani A.Rich, and Vetiveria zizanoides Nash. Our work can help fill the gap in the literature and guide further in vitro and in vivo studies, intending to optimize the finding of effective EOs against COVID-19.

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Identifying plant species requires considerable knowledge and can be difficult without complete specimens. Fourier-transform near-infrared spectroscopy (FT-NIR) is an effective technique for discriminating plant species, especially angiosperms. However, its efficacy has never been tested on ferns. Here we tested the accuracy of FT-NIR at discriminating species of the genus Microgramma. We obtained 16 spectral readings per individual from the adaxial and abaxial surfaces of 100 specimens belonging to 13 species. The analyses included all 1557 spectral variables. We tested different datasets (adaxial + abaxial, adaxial, and abaxial) to compare the correct identification of species through the construction of discriminant models (Linear discriminant analysis and partial least squares discriminant analysis) and cross-validation techniques (leave-one-out, K-fold). All analyses recovered an overall high percentage (> 90%) of correct predictions of specimen identifications for all datasets, regardless of the model or cross-validation used. On average, there was > 95% accuracy when using partial least squares discriminant analysis and both cross-validations. Our results show the high predictive power of FT-NIR at correctly discriminating fern species when using leaves of dried herbarium specimens. The technique is sensitive enough to reflect species delimitation problems and possible hybridization, and it has the potential of helping better delimit and identify fern species.

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BACKGROUND: Hybridization is an evolutionary event present in the natural world. Several studies suggest that natural hybridization is an important process in plant evolution, creating new genetic combinations which can play a vital role in speciation (Soltis and Soltis 2009, Soltis 2013, Neri et al. 2017, Taylor and Larson 2019). Therefore, it is important to understand and protect naturally occurring hybrids, conserving their ecological novelties and new traits, such as the ability to explore new niches, different from those of the parental species (Soltis 2013, Supple and Shapiro 2018).The British Virgin Islands (BVI) is a UK Overseas Territory situated in the Caribbean biodiversity hotspot (Myers et al. 2000). To date, three natural hybrids are known to occur within this territory: Tillandsia × lineatispica Mez, Anthurium × selloanum K.Koch and Coccoloba krugii × C. uvifera R.A.Howard (Howard 1957, Acevedo-Rodriguez and Strong 2005, Acevedo-Rodriguez and Strong 2012).Tillandsia × lineatispica is endemic to the Puerto Rican Bank, occurring in Puerto Rico, the US Virgin Islands (USVI) and the British Virgin Islands with an extent of occurrence estimated to be 3,390 km2 and a limited number of locations. The suitable habitat for this hybrid is declining mainly due to the negative impacts of feral ungulates, development for tourism and residential infrastructure and the impact of human-induced wildfires. In addition, it is suspected that the global population does not exceed 10,000 individuals with the largest subpopulation on Beef Island in the BVI thought to have no more than 1,000 mature individuals. This hybrid is therefore evaluated as Vulnerable, based on IUCN Red List Criteria, B1a(iii)+2b(iii) + C2a(i).Anthurium × selloanum is an endemic hybrid to BVI and USVI with a very restricted extent of occurrence which was estimated to range between 103 km2 and 207 km2 and an area of occupancy which was estimated to range between 56 km2 and 188 km2 and a limited number of locations. The suitable habitat of this species is declining mainly due to the negative impacts of feral ungulates, development for tourism and residential infrastructure and the negative impact of recreation activities in protected areas. This species is therefore evaluated as Endangered, based on IUCN Red List Criteria B1a+ b(iii) + B2a+b(iii).Coccoloba krugii × C. uvifera is native to the BVI, USVI, Puerto Rico, Dominican Republic, Haiti and Anguilla. It is estimated to have an extent of occurrence of 89,412 km2. This value exceeds the threshold for any threatened category. Despite an observed continuing decline of suitable habitat for this species, which is being degraded mainly through ongoing development pressures, this species occurs in more than 10 locations. It is therefore assessed as Least Concern (LC). NEW INFORMATION: In this paper, we discuss the conservation status of all the known, naturally occurring, native hybrids in the the British Virgin Islands and we provide distribution data, including new records, from across these hybrid species ranges. Although conservation assessments of hybrids are out of the scope of the published IUCN Red List of Threatened Species (IUCN Standards and Petitions Committee 2019), we use the IUCN Red List Criteria and Categories (version 3.1) to establish an equivalent conservation status of these hybrids and discuss conservation action due to the potential evolutionary importance of these naturally occurring hybrids. These assessments provide the necessary baseline information for prioritising species conservation and making informed management decisions, such as establishing the BVI's Tropical Important Plant Areas (TIPAS) network (Sanchez et al. 2019).

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Regrowth via production of epicormic shoots is an important strategy for many woody plants after environmental disturbances such as fire, drought, and herbivory. Populations spreading across a broad latitudinal gradient offer opportunities to investigate if essential traits vary with heterogenous environmental conditions, such as in savanna ecosystems. This information can help us predict plant responses to climate change. Here, we evaluated if epicormic bud protection traits varied among populations of three focal savanna species (Miconia albicans, Solanum lycocarpum, and Zeyheria montana) that have a wide distribution and grow under variable climatic conditions. We randomly sampled 225 individuals over five spatially independent sites (7°, 10°, 15°, 18°, and 24° S) in Brazil, totaling 15 individuals per species per area. We analyzed anatomical transverse sections of five buds per species per area to assess the relative area occupied by crystal and phenolic idioblasts, the thickness of the trichome boundary layer, and to test if these traits were associated with climatic conditions. The buds were protected by cataphylls and composed of a variable number of undeveloped leaves enveloping the shoot apex. For M. albicans, we found an association between maximum temperature and both phenolic idioblasts and trichome boundary layer, but no association with crystal idioblasts. In S. lycocarpum, only the trichome boundary layer was associated with maximum temperature plus high radiation. Z. montana showed no variation. Combination of two or more traits can lead to the development of adaptative strategies to different climatic conditions. We present for the first time an analysis of epicormic bud traits in plant populations occurring in an extensive latitudinal gradient and shed light on how maximum temperature is associated with these traits, contributing to a better understanding of plant resprouting capabilities in widespread savanna plant species.

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Recently, many studies have reported the anticancer properties of flavonoid luteolin against a variety of tumors, but there is still a lack in the description of its mechanism of action. In attempt to better contribute to the literature, we evaluated the antiproliferative activity of luteolin extracted by Fridericia platyphylla in a panel of tumor cell lines representative of six different tissues. Luteolin presented antiproliferative activity for all the assessed tumor cell lines, being glioblastoma the most sensitive one. This compound was able to inhibit U-251 cells migration and tumorigenesis. Besides, luteolin leads U-251 tumor cells to apoptosis death by depolarisation of the mitochondrial membrane, ERK proteins phosphorylation, cleavage of PARP and Caspase 9, further inducing DNA damage by H2AX phosphorylation, which had not yet been described for glioblastomas. Altogether, our results reaffirm luteolin as a potential therapeutic drug.

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Abstract: A list of plant species, in alphabetical order by their scientific name, and the viruses found naturally infecting them in Brazilian territory, with some comments, was prepared . The production of such a list was based on a yearly catalog of publications on plant viruses collected by the author, from 1926 to 2018. Listed species of viruses were those recognized by the International Committee on Taxonomy of Viruses (ICTV), but also those characterized and still waiting official recognition, were included. Several cases of putative viral diseases were listed for historical reasons expecting to raise interest for their clarification. This list includes 345 plants species belonging to 74 families naturally infected by plant viruses in Brazil. Fabaceae and Asteraceae had most virus-infected species, respectively 49 and 36. Until 2018, a total of 213 plant virus and 6 viroid species belonging to 57 genera and 22 families and 6 orders, officially recognized by ICTV, were found naturally infecting these plants. Begomovirus and Potyvirus genera have most representatives, with 45 and 42 species, respectively. There are 59 characterized plant viruses, up to species level, described in Brazil waiting for the inclusion in the ICTV Master Species List. One hundred and thirteen viruses were identified up to genus level but still uncharacterized, while four putative isometric viruses and eleven presumptive viral diseases ("unidentified") are included in the list. A reverse catalog, listing viruses and the plant species in which they were found is also included.

Resumo: Esta publicação consiste em uma listagem de espécies de plantas, em ordem alfabética de seus nomes científicos, e dos vírus que foram encontrados naturalmente infetando-as em território brasileiro, com alguns comentários. O preparo de tal lista foi basedo nas publicações sobre vírus de plantas e as doenças que eles causam, colecionadas pelo autor de 1926 a 2018. Os vírus listados incluem aqueles já oficialmente reconhecidos pelo International Committee on Taxonomy of Viruses (ICTV), constantes do "Master Species List 2018". Também estão incluídos vírus já caracterizados, aguardando oficialização pelo ICTV, e outros casos de possíveis viroses, cujo agente causal ainda não se acha adequadamente caracterizado. A listagem inclui 345 espécies de plantas, pertencentes a 74 famílias, que foram encontradas naturalmente infetadas por diferentes vírus. Fabáceas e Asteráceas foram as famílias que tiveram mais espécies infetadas por vírus, respectivamente 49 e 36. Até 2018, 213 espécies de vírus e 6 de viróides, pertencentes a 57 gêneros e 22 famílias e 6 ordens, oficialmente reconhecidas pelo ICTV, acham-se descritas no Brasil. Os gêneros Begomovirus e Potyvirus têm mais espécies representadas, com 45 e 42 respectivamente. Além das espécies identificadas e aceitas pelo ICTV, foram incluídas na lista 59 possíveis espécies que ainda aguardam oficialização, 113 vírus identificados a nível de gênero, quatro possíveis vírus isométricos e onze presumíveis viroses, de agentes etiológicos não confirmados. Foi incluída também uma lista reversa, com catalogação dos vírus e viróides descritos no Brasdil e suas respectivas plantas hospedeiras.

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Alzheimer's disease (AD) is a main cause of dementia, accounting for up to 75% of all dementia cases. Pathophysiological processes described for AD progression involve neurons and synapses degeneration, mainly characterized by cholinergic impairment. This feature makes acetylcholinesterase inhibitors (AChEi) the main class of drugs currently used for the treatment of AD dementia phase, among which galantamine is the only naturally occurring substance. However, several plant species producing diverse classes of alkaloids, coumarins, terpenes, and polyphenols have been assessed for their anti-AChE activity, becoming potential candidates for new anti-AD drugs. Therefore, this mini-review aimed to recapitulate last decade studies on the anti-AChE activity of plant species, their respective extracts, as well as isolated compounds. The anti-AChE activity of extracts prepared from 54 plant species pertaining 29 families, as well as 36 isolated compounds were classified and discussed according to their anti-AChE pharmacological potency to highlight the most prominent ones. Besides, relevant limitations, such as proper antioxidant assessment, and scarcity of toxicological and clinical studies were also discussed in order to help researchers out with the bioprospection of potentially new AChEi.

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Native bees contribute a considerable portion of pollination services for endemic as well as introduced plant species. Their decline has been attributed to several human-derived influences including global warming as well as the reduction, alteration, and loss of bees' habitat. With human expansion comes along the introduction of exotic plant species with negative impacts over native ecosystems. Anthropic effects may even have a deeper impact on communities adapted to extreme environments, such as high elevation habitats, where abiotic stressors alone are a natural limitation to biodiversity. Among these effects, the introduction of exotic plants and urbanization may have a greater influence on native communities. In this work, we explored such problems, studying the relationship between the landscape and its effect over richness and abundance of native bees from the subandean belt in the Andes mountain chain. Furthermore, we investigated the effects of exotic plant abundance on this high-altitude bee assemblage. Despite the landscape not showing an effect over bee richness and abundance, exotic plants did have a significant influence over the native bee assemblage. The abundance of exotic plants was associated with a relative increase in the proportion of small and medium bee species. Moreover, Halictidae was the only family that appeared to be favored by an increase in the abundance of exotic plant species. We discuss these results and the urgent need for further research of high-altitude environments due to their vulnerability and high endemicity.

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Metal contamination is a recurring problem in Peru, caused mainly by mine tailings from a past active mining activity. The Ancash region has the largest number of environmental liabilities, which mobilizes high levels of metals and acid drainages into soils and freshwater sources, posing a standing risk on human and environmental health. Native plant species spontaneously growing on naturally acidified soils and acid mine tailings show a unique tolerance to high metal concentrations and are thus potential candidates for soil phytoremediation. However, little is known about their propagation capacity and metal accumulation under controlled conditions. In this study, we aimed at characterizing nine native plant species, previously identified as potential hyperaccumulators, from areas impacted by mine tailings in the Ancash region. Plants were grown on mine soils under greenhouse conditions during 5 months, after which the concentration of Cd, Cu, Ni, Pb, and Zn was analyzed in roots, shoots, and soils. The bioaccumulation (BAF) and translocation factor (TF) were calculated to determine the amount of each metal accumulated in the roots and shoots and to identify which species could be better suited for phytoremediation purposes. Soil samples contained high Cd (6.50-49.80 mg/kg), Cu (159.50-1187.00 mg/kg), Ni (3.50-8.70 mg/kg), Pb (1707.00-4243.00 mg/kg), and Zn (909.00-7100.00 mg/kg) concentrations exceeding national environmental quality standards. After exposure to mine tailings, concentrations of metals in shoots were highest in Werneria nubigena (Cd, 16.68 mg/kg; Cu, 41.36 mg/kg; Ni, 26.85 mg/kg; Zn, 1691.03 mg/kg), Pennisetum clandestinum (Pb, 236.86 mg/kg), and Medicago lupulina (Zn, 1078.10 mg/kg). Metal concentrations in the roots were highest in Juncus bufonius (Cd, 34.34 mg/kg; Cu, 251.07 mg/kg; Ni, 6.60 mg/kg; Pb, 718.44 mg/kg) and M. lupulina (Zn, 2415.73 mg/kg). The greatest BAF was calculated for W. nubigena (Cd, 1.92; Cu, 1.20; Ni, 6.50; Zn, 3.50) and J. bufonius (Ni, 3.02; Zn, 1.30); BCF for Calamagrostis recta (Cd, 1.09; Cu, 1.80; Ni, 1.09), J. bufonius (Cd, 3.91; Cu, 1.79; Ni, 18.36), and Achyrocline alata (Ni, 137; Zn, 1.85); and TF for W. nubigena (Cd, 2.36; Cu, 1.70; Ni, 2.42; Pb, 1.17; Zn, 1.43), A. alata (Cd, 1.14; Pb, 1.94), J. bufonius (Ni, 2.72; Zn, 1.63), and P. clandestinum (Zn, 1.14). Our results suggest that these plant species have a great potential for soil phytoremediation, given their capability to accumulate and transfer metals and their tolerance to highly metal-polluted environments in the Andean region.

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Plant-microbial interactions in the litter layer represent one of the most relevant interactions for biogeochemical cycling as litter decomposition is a key first step in carbon and nitrogen turnover. However, our understanding of these interactions in the litter layer remains elusive. In an old-growth mixed Nothofagus forest in Patagonia, we studied the effects of single tree species identity and the mixture of three tree species on the fungal and bacterial composition in the litter layer. We also evaluated the effects of nitrogen (N) addition on these plant-microbial interactions. In addition, we compared the magnitude of stimulation of litter decomposition due to home field advantage (HFA, decomposition occurs more rapidly when litter is placed beneath the plant species from which it had been derived than beneath a different plant species) and N addition that we previously demonstrated in this same forest, and used microbial information to interpret these results. Tree species identity had a strong and significant effect on the composition of fungal communities but not on the bacterial community of the litter layer. The microbial composition of the litter layer under the tree species mixture show an averaged contribution of each single tree species. N addition did not erase the plant species footprint on the fungal community, and neither altered the bacterial community. N addition stimulated litter decomposition as much as HFA for certain tree species, but the mechanisms behind N and HFA stimulation may have differed. Our results suggest that stimulation of decomposition from N addition might have occurred due to increased microbial activity without large changes in microbial community composition, while HFA may have resulted principally from plant species' effects on the litter fungal community. Together, our results suggest that plant-microbial interactions can be an unconsidered driver of litter decomposition in temperate forests.

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Saproxylic insects depend on deadwood for larval development, and a certain degree of specialization may be involved in their choice of host plants and/or wood in a particular stage of degradation. The plant species chosen for oviposition in turn act as an environmental pressure on the head morphology of larvae and it is expected that head shape plasticity varies directly with the number of woody plant species used for larval development in each insect species. We analyzed head shape variation in saproxylic beetles with respect to host plant species, maximum time of larval emergence and season of the year when insects colonized branches. Generalist species in the use of host plants showed significant variation in head shape and size. Time of emergence and season did not appear to affect head shape, although season was a determinant factor of abundance and possibly head size variation.

Assuntos

RESUMO

An increasing number of studies have aimed to clarify the factors leading human groups to prioritize the use of some woody plant species compared to others. Some of these studies have tested the apparency hypothesis in aiming to understand this phenomenon. According to the apparency hypothesis, the most commonly available local plant species on a forest path are the most useful to that local human population. However, the sparse and diverse nature of the results from studies investigating the factors that influence human exploitation of plant resources motivated us to perform a meta-analysis on the apparency hypothesis. We searched in the main databases (Scopus, ScienceDirect, Google Scholar, and Scielo) for studies that correlated the environmental availability of woody species (estimated through vegetation parameters) with the degree of importance of such species to the local human population (estimated by means of the use value index). Overall, this meta-analysis supported the apparency hypothesis, although we also found high levels of heterogeneity in these studies. When the distinct uses of woody flora were considered separately, we found that local species availability is important for fuelwood (firewood and charcoal) and construction (houses, fences, etc.) purposes but does not explain medicinal and technological (object manufacture) plant use. We found no important differences in correlation values between the degree of species importance for people and the different vegetation parameters, although correlations are slightly higher for the dominance and importance value index. Our findings suggest that the exploitation of woody flora is influenced by local availability.

Assuntos

RESUMO

This study investigated the spatial distribution of an Amazonian fruit-feeding butterfly assemblage by linking species taxonomic and functional approaches. We hypothesized that: 1) vegetation richness (i.e., resources) and abundance of insectivorous birds (i.e., predators) should drive changes in butterfly taxonomic composition, 2) larval diet breadth should decrease with increase of plant species richness, 3) small-sized adults should be favored by higher abundance of birds, and 4) communities with eyespot markings should be able to exploit areas with higher predation pressure. Fruit-feeding butterflies were sampled with bait traps and insect nets across 25 km(2) of an Amazonian ombrophilous forest in Brazil. We measured larval diet breadth, adult body size, and wing marking of all butterflies. Our results showed that plant species richness explained most of the variation in butterfly taxonomic turnover. Also, community average diet breadth decreased with increase of plant species richness, which supports our expectations. In contrast, community average body size increased with the abundance of birds, refuting our hypothesis. We detected no influence of environmental gradients on the occurrence of species with eyespot markings. The association between butterfly taxonomic and functional composition points to a mediator role of the functional traits in the environmental filtering of butterflies. The incorporation of the functional approach into the analyses allowed for the detection of relationships that were not observed using a strictly taxonomic perspective and provided an extra insight into comprehending the potential adaptive strategies of butterflies.

Assuntos