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1.
New Phytol ; 242(4): 1436-1440, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38594221

RESUMO

Global assessments of mycorrhizal symbiosis present large sampling gaps in rich biodiversity regions. Filling these gaps is necessary to build large-scale, unbiased mycorrhizal databases to obtain reliable analyses and prevent misleading generalizations. Underrepresented regions in mycorrhizal research are mainly in Africa, Asia, and South America. Despite the high biodiversity and endemism in these regions, many groups of organisms remain understudied, especially mycorrhizal fungi. In this Viewpoint, we emphasize the importance of inclusive and collaborative continental efforts in integrating perspectives for comprehensive trait database development and propose a conceptual framework that can help build large mycorrhizal databases in underrepresented regions. Based on the four Vs of big data (volume, variety, veracity, and velocity), we identify the main challenges of constructing a large mycorrhizal dataset and propose solutions for each challenge. We share our collaborative methodology, which involves employing open calls and working groups to engage all mycorrhizal researchers in the region to build a South American Mycorrhizal Database. By fostering interdisciplinary collaborations and embracing a continental-scale approach, we can create robust mycorrhizal trait databases that provide valuable insights into the evolution, ecology, and functioning of mycorrhizal associations, reducing the geographical biases that are so common in large-scale ecological studies.


Assuntos
Micorrizas , Simbiose , Biodiversidade , Bases de Dados Factuais , Micorrizas/fisiologia , Característica Quantitativa Herdável
2.
Mycorrhiza ; 34(1-2): 107-117, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38151658

RESUMO

The Andean paramo, hereafter "paramo", is a Neotropical high-mountain region between the treeline and permanent snowline (3500-4800 m) and is considered the world's coolest biodiversity hotspot. Because of paramo's high humidity, solar radiation and temperature variation, mycorrhizal symbiosis is expected to be essential for plants. Existing theory suggests that replacement of arbuscular mycorrhizal (AM) by ectomycorrhizal (ECM) and then ericoid mycorrhizal plants (ERM) can be expected with increasing elevation. Previous findings also suggest that non-(NM) and facultatively mycorrhizal (FM) species predominate over obligatory mycorrhizal (OM) species at high elevations. However, these expectations have never been tested outside of the northern temperate zone. We addressed the distribution and environmental drivers of plant mycorrhizal types (AM, ECM and ERM) and statuses (NM, FM and OM) along the paramo's elevational gradient. We used vegetation plots from the VegParamo database, climatic and edaphic data from online repositories, and up-to-date observation information about plant mycorrhizal traits at species and genus level, the latter being proposed as hypotheses. AM plants were dominant along the entire gradient, and ERM plants were most abundant at the lowest elevations (2500-3000 m). The share of FM plants increased and that of OM plants decreased with elevation, while NM plants increased above 4000 m. Temperature and soil pH were positively related to the abundance of AM plants and negatively to ERM plants. Our results reveal patterns that contrast with those observed in temperate northern-hemisphere ecosystems.


Assuntos
Micorrizas , Simbiose , Ecossistema , Plantas , Biodiversidade , Solo , Microbiologia do Solo
4.
Ecol Lett ; 26(11): 1862-1876, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37766496

RESUMO

Mycorrhizal symbioses are known to strongly influence plant performance, structure plant communities and shape ecosystem dynamics. Plant mycorrhizal traits, such as those characterising mycorrhizal type (arbuscular (AM), ecto-, ericoid or orchid mycorrhiza) and status (obligately (OM), facultatively (FM) or non-mycorrhizal) offer valuable insight into plant belowground functionality. Here, we compile available plant mycorrhizal trait information and global occurrence data ( ∼ 100 million records) for 11,770 vascular plant species. Using a plant phylogenetic mega-tree and high-resolution climatic and edaphic data layers, we assess phylogenetic and environmental correlates of plant mycorrhizal traits. We find that plant mycorrhizal type is more phylogenetically conserved than plant mycorrhizal status, while environmental variables (both climatic and edaphic; notably soil texture) explain more variation in mycorrhizal status, especially FM. The previously underestimated role of environmental conditions has far-reaching implications for our understanding of ecosystem functioning under changing climatic and soil conditions.


Assuntos
Micorrizas , Micorrizas/genética , Ecossistema , Filogenia , Microbiologia do Solo , Plantas , Solo/química
6.
Front Plant Sci ; 14: 1106617, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143888

RESUMO

Introduction: Traditional approaches to collecting large-scale biodiversity data pose huge logistical and technical challenges. We aimed to assess how a comparatively simple method based on sequencing environmental DNA (eDNA) characterises global variation in plant diversity and community composition compared with data derived from traditional plant inventory methods. Methods: We sequenced a short fragment (P6 loop) of the chloroplast trnL intron from from 325 globally distributed soil samples and compared estimates of diversity and composition with those derived from traditional sources based on empirical (GBIF) or extrapolated plant distribution and diversity data. Results: Large-scale plant diversity and community composition patterns revealed by sequencing eDNA were broadly in accordance with those derived from traditional sources. The success of the eDNA taxonomy assignment, and the overlap of taxon lists between eDNA and GBIF, was greatest at moderate to high latitudes of the northern hemisphere. On average, around half (mean: 51.5% SD 17.6) of local GBIF records were represented in eDNA databases at the species level, depending on the geographic region. Discussion: eDNA trnL gene sequencing data accurately represent global patterns in plant diversity and composition and thus can provide a basis for large-scale vegetation studies. Important experimental considerations for plant eDNA studies include using a sampling volume and design to maximise the number of taxa detected and optimising the sequencing depth. However, increasing the coverage of reference sequence databases would yield the most significant improvements in the accuracy of taxonomic assignments made using the P6 loop of the trnL region.

7.
Leukemia ; 37(5): 988-1005, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019990

RESUMO

Chromosomal rearrangements of the human KMT2A/MLL gene are associated with de novo as well as therapy-induced infant, pediatric, and adult acute leukemias. Here, we present the data obtained from 3401 acute leukemia patients that have been analyzed between 2003 and 2022. Genomic breakpoints within the KMT2A gene and the involved translocation partner genes (TPGs) and KMT2A-partial tandem duplications (PTDs) were determined. Including the published data from the literature, a total of 107 in-frame KMT2A gene fusions have been identified so far. Further 16 rearrangements were out-of-frame fusions, 18 patients had no partner gene fused to 5'-KMT2A, two patients had a 5'-KMT2A deletion, and one ETV6::RUNX1 patient had an KMT2A insertion at the breakpoint. The seven most frequent TPGs and PTDs account for more than 90% of all recombinations of the KMT2A, 37 occur recurrently and 63 were identified so far only once. This study provides a comprehensive analysis of the KMT2A recombinome in acute leukemia patients. Besides the scientific gain of information, genomic breakpoint sequences of these patients were used to monitor minimal residual disease (MRD). Thus, this work may be directly translated from the bench to the bedside of patients and meet the clinical needs to improve patient survival.


Assuntos
Histona-Lisina N-Metiltransferase , Leucemia Mieloide Aguda , Proteína de Leucina Linfoide-Mieloide , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Fusão Gênica
8.
Front Plant Sci ; 14: 1100235, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36743494

RESUMO

Our knowledge of microbial biogeography has advanced in recent years, yet we lack knowledge of the global diversity of some important functional groups. Here, we used environmental DNA from 327 globally collected soil samples to investigate the biodiversity patterns of nitrogen-fixing bacteria by focusing on the nifH gene but also amplifying the general prokaryotic 16S SSU region. Globally, N-fixing prokaryotic communities are driven mainly by climatic conditions, with most groups being positively correlated with stable hot or seasonally humid climates. Among soil parameters, pH, but also soil N content were most often shown to correlate with the diversity of N-fixer groups. However, specific groups of N-fixing prokaryotes show contrasting responses to the same variables, notably in Cyanobacteria that were negatively correlated with stable hot climates, and showed a U-shaped correlation with soil pH, contrary to other N-fixers. Also, the non-N-fixing prokaryotic community composition was differentially correlated with the diversity and abundance of N-fixer groups, showing the often-neglected impact of biotic interactions among bacteria.

9.
Sci Total Environ ; 857(Pt 3): 159633, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36280064

RESUMO

Microplastics (MPs) represent an emergent contamination marker. For this reason, we analyzed the vertical distribution of MPs in six sediment cores retrieved from the Patos-Mirim System, the world's largest coastal lagoonal system. The sediment cores span from mid Holocene to present times according to both radiocarbon and lead dating and are located close to both urban/industrial and agricultural regions. We identified a basal pre-disturbance MP-free zone in all cores and an uppermost contaminated 70-cm-zone, where a general increasing trend in MPs content resembling the human anthropization process was recorded. The predominant format of MPs was fiber, followed by fragments. The most commonly identified polymers were rayon, PVC, acrylate, polycarbonate and cellophane. Urban/industrial and agricultural activities were shown as clear sources of MPs, leading to comparable MPs concentration values in the sediment cores. Thus, MPs are collectively a reliable indicator of the Anthropocene onset, and in the Patos-Mirim System the most appropriate chronology can be assigned to the beginning of 1970s, matching the intensification of anthropogenic activities in the area.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Sedimentos Geológicos , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Biomarcadores , América do Sul
10.
Animals (Basel) ; 12(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36230261

RESUMO

Native wild boar (Sus scrofa) populations are expanding across Europe. This is cause for concern in some areas where overabundant populations impact natural ecosystems and adjacent agronomic systems. To better manage the potential for impacts, managers require more information about how the species may affect other organisms. For example, information regarding the effect of wild boar on soil fungi for management application is lacking. Soil fungi play a fundamental role in ecosystems, driving essential ecological functions; acting as mycorrhizal symbionts, sustaining plant nutrition and providing defense; as saprotrophs, regulating the organic matter decomposition; or as plant pathogens, regulating plant fitness and survival. During autumn (Sep-Nov) 2018, we investigated the effects of wild boar (presence/absence and rooting intensity) on the abundance (number of individuals) of fungal sporocarps and their functional guilds (symbiotic, saprotrophic and pathogenic). We selected eleven forested sites (400-500 × 150-200 m) in central Sweden; six with and five without the presence of wild boar. Within each forest, we selected one transect (200 m long), and five plots (2 × 2 m each) for sites without wild boar, and ten plots for sites with boars (five within and five outside wild boar disturbances), to determine the relationship between the intensity of rooting and the abundance of sporocarps for three fungal guilds. We found that the presence of wild boar and rooting intensity were associated with the abundance of sporocarps. Interestingly, this relationship varied depending on the fungal guild analyzed, where wild boar rooting had a positive correlation with saprophytic sporocarps and a negative correlation with symbiotic sporocarps. Pathogenic fungi, in turn, were more abundant in undisturbed plots (no rooting) but located in areas with the presence of wild boar. Our results indicate that wild boar activities can potentially regulate the abundance of fungal sporocarps, with different impacts on fungal guilds. Therefore, wild boar can affect many essential ecosystem functions driven by soil fungi in boreal forests, such as positive effects on energy rotation and in creating mineral availability to plants, which could lead to increased diversity of plants in boreal forests.

11.
Ecology ; 103(9): e3761, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35582944

RESUMO

Classical theory identifies resource competition as the major structuring force of biotic communities and predicts that (i) levels of dominance and richness in communities are inversely related, (ii) narrow niches allow dense "packing" in niche space and thus promote diversity, and (iii) dominants are generalists with wide niches, such that locally abundant taxa also exhibit wide distributions. Current empirical support, however, is mixed. We tested these expectations using published data on arbuscular mycorrhizal (AM) fungal community composition worldwide. We recorded the expected negative relationship between dominance and richness and, to a degree, the positive association between local and global dominance. However, contrary to expectations, dominance was pronounced in communities where more specialists were present and, conversely, richness was higher in communities with more generalists. Thus, resource competition and niche packing appear to be of limited importance in AM fungal community assembly; rather, patterns of dominance and diversity seem more consistent with habitat filtering and stochastic processes.


Assuntos
Micobioma , Micorrizas , Ecossistema , Solo , Microbiologia do Solo
12.
Mycorrhiza ; 32(2): 135-144, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35138435

RESUMO

Arbuscular mycorrhizal (AM) fungi are a ubiquitous group of plant symbionts, yet processes underlying their global assembly - in particular the roles of dispersal limitation and historical drivers - remain poorly understood. Because earlier studies have reported niche conservatism in AM fungi, we hypothesized that variation in taxonomic community composition (i.e., unweighted by taxon relatedness) should resemble variation in phylogenetic community composition (i.e., weighted by taxon relatedness) which reflects ancestral adaptations to historical habitat gradients. Because of the presumed strong dispersal ability of AM fungi, we also anticipated that the large-scale structure of AM fungal communities would track environmental conditions without regional discontinuity. We used recently published AM fungal sequence data (small-subunit ribosomal RNA gene) from soil samples collected worldwide to reconstruct global patterns in taxonomic and phylogenetic community variation. The taxonomic structure of AM fungal communities was primarily driven by habitat conditions, with limited regional differentiation, and there were two well-supported clusters of communities - occurring in cold and warm conditions. Phylogenetic structure was driven by the same factors, though all relationships were markedly weaker. This suggests that niche conservatism with respect to habitat associations is weakly expressed in AM fungal communities. We conclude that the composition of AM fungal communities tracks major climatic and edaphic gradients, with the effects of dispersal limitation and historic factors considerably less apparent than those of climate and soil.


Assuntos
Micobioma , Micorrizas , Fungos/genética , Micorrizas/genética , Filogenia , Solo , Microbiologia do Solo
13.
Clin Transl Oncol ; 24(2): 342-349, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34487307

RESUMO

PURPOSE/OBJECTIVE(S): Stereotactic body radiotherapy (SBRT) has become the standard of care for patients with medically inoperable early-stage non-small cell lung cancer (NSCLC) and for patients who refuse surgery. The aim of this study was to evaluate the effectiveness and safety of primary SBRT in patients with early-stage NSCLC. MATERIALS/METHODS: Retrospective multicenter study of 397 patients (416 primary lung tumours) treated with SBRT at 18 centres in Spain. 83.2% were men. The median age was 74.4 years. In 94.4% of cases, the tumour was inoperable. The pathological report was available in 54.6% of cases. SPSS vs 22.0. was used to perform all statistical analyses. RESULTS: Complete response was obtained in 53.6% of cases. Significant prognostic factors were standard CT planning (p = 0.014) and 4D cone beam CT (p = 0.000). Acute and chronic toxicity ≥ grade 3 was observed in 1.2% of cases. At a median follow-up of 30 months, local relapse was 9.6%, lymph node relapse 12.8%, distant metastasis 16.6%, and another lung tumour 11.5%. Complete response was the only significant prognostic factor for local relapse (p = 0.012) and distant metastasis (p = 0.001). The local relapse-free survival was 88.7%. The overall survival was 75.7%. The cancer-specific survival was 92.7%. The disease-free survival was 78.7%. CONCLUSION: SBRT is an effective and well-tolerated treatment option for patients with early-stage lung cancer who are not suitable for surgery. The most important prognostic factor for local and distant recurrence was complete response, which in our sample depended on the type of CT planning and the IGRT technique.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
14.
Front Microbiol ; 12: 743512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759901

RESUMO

Drought stress is an alarming constraint to plant growth, development, and productivity worldwide. However, plant-associated bacteria, fungi, and viruses can enhance stress resistance and cope with the negative impacts of drought through the induction of various mechanisms, which involve plant biochemical and physiological changes. These mechanisms include osmotic adjustment, antioxidant enzyme enhancement, modification in phytohormonal levels, biofilm production, increased water and nutrient uptake as well as increased gas exchange and water use efficiency. Production of microbial volatile organic compounds (mVOCs) and induction of stress-responsive genes by microbes also play a crucial role in the acquisition of drought tolerance. This review offers a unique exploration of the role of plant-associated microorganisms-plant growth promoting rhizobacteria and mycorrhizae, viruses, and their interactions-in the plant microbiome (or phytobiome) as a whole and their modes of action that mitigate plant drought stress.

15.
Nature ; 597(7878): 683-687, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34588667

RESUMO

Plant traits determine how individual plants cope with heterogeneous environments. Despite large variability in individual traits, trait coordination and trade-offs1,2 result in some trait combinations being much more widespread than others, as revealed in the global spectrum of plant form and function (GSPFF3) and the root economics space (RES4) for aboveground and fine-root traits, respectively. Here we combine the traits that define both functional spaces. Our analysis confirms the major trends of the GSPFF and shows that the RES captures additional information. The four dimensions needed to explain the non-redundant information in the dataset can be summarized in an aboveground and a fine-root plane, corresponding to the GSPFF and the RES, respectively. Both planes display high levels of species aggregation, but the differentiation among growth forms, families and biomes is lower on the fine-root plane, which does not include any size-related trait, than on the aboveground plane. As a result, many species with similar fine-root syndromes display contrasting aboveground traits. This highlights the importance of including belowground organs to the GSPFF when exploring the interplay between different natural selection pressures and whole-plant trait integration.


Assuntos
Ecossistema , Fenômenos Fisiológicos Vegetais , Raízes de Plantas/fisiologia , Plantas/classificação , Fenótipo , Desenvolvimento Vegetal , Análise de Componente Principal
16.
Nat Commun ; 12(1): 5162, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34453040

RESUMO

Although species with larger body size and slow pace of life have a higher risk of extinction at a global scale, it is unclear whether this global trend will be consistent across biogeographic realms. Here we measure the functional diversity of terrestrial and freshwater vertebrates in the six terrestrial biogeographic realms and predict their future changes through scenarios mimicking a gradient of extinction risk of threatened species. We show vastly different effects of extinctions on functional diversity between taxonomic groups and realms, ranging from almost no decline to deep functional losses. The Indo-Malay and Palearctic realms are particularly inclined to experience a drastic loss of functional diversity reaching 29 and 31%, respectively. Birds, mammals, and reptiles regionally display a consistent functional diversity loss, while the projected losses of amphibians and freshwater fishes differ across realms. More efficient global conservation policies should consider marked regional losses of functional diversity across the world.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção/estatística & dados numéricos , Vertebrados/classificação , Animais , Conservação dos Recursos Naturais , Ecossistema , Extinção Biológica , Vertebrados/crescimento & desenvolvimento
17.
Sci Total Environ ; 801: 149664, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34418619

RESUMO

The palaeolimnological conditions of Mirim Lagoon, a large coastal shallow lagoon under the influence of historical human impacts related to the development of the primary sector of the economy were reconstructed. The first significant human impact consisted of locking the estuarine system to induce the transition from brackish to freshwater conditions. During this transition, the sedimentation rate consistently increased from pre-disturbance values of 0.25 cm yr-1 to >1 cm yr-1. A concomitant increase in nitrogen and carbon values was recorded indicating a related eutrophication process. The highest nutrient levels were achieved during the 1990s after the incorporation of cutting-edge technologies for agricultural production such as high-yielding varieties of rice resistant to climate variability and pests, and the use of inorganic fertilisers, pesticides and water supply controlled by irrigation. After 2011, the soybean production boosted and the area cultivated with this oilseed equalled the area of rice paddies, i.e., 2 × 105 ha. A sharp decrease in δ13C from -19 to -24‰ and in δ15N from 6 to 2‰ were observed in the sedimentary record, indicating a major shift in the composition of the organic matter after the agricultural intensification. Trace elements Cr, Cu, Ni and Zn showed a high positive correlation with Al and Fe, and enrichment factors near 1, indicating a natural and terrigenous source of these elements and also unpolluted conditions. However, the increase of As after 1990 and the positive correlation with Pb was associated with agricultural practices. All elemental ratios (K/Al, Ti/Al and V/Cr) showed constant pre-disturbance trends and a turning point ca. the 1990s. Microplastics were detected from the beginning of the 1990s and increased towards recent sediments, thus corroborating an anthropogenically impacted scenario. Therefore, the development of the primary sector of the economy exerted clear impacts on the environmental quality of the system.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Monitoramento Ambiental , Eutrofização , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Plásticos , Oligoelementos/análise , Água , Poluentes Químicos da Água/análise
19.
Ann Bot ; 128(1): 97-113, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33821947

RESUMO

BACKGROUND AND AIMS: Daylength determines flowering dates. However, questions remain regarding flowering dates in the natural environment, such as the synchronous flowering of plants sown simultaneously at highly contrasting latitudes. The daily change in sunrise and sunset times is the cue for the flowering of trees and for the synchronization of moulting in birds at the equator. Sunrise and sunset also synchronize the cell circadian clock, which is involved in the regulation of flowering. The goal of this study was to update the photoperiodism model with knowledge acquired since its conception. METHODS: A large dataset was gathered, including four 2-year series of monthly sowings of 28 sorghum varieties in Mali and two 1-year series of monthly sowings of eight rice varieties in the Philippines to compare with previously published monthly sowings in Japan and Malaysia, and data from sorghum breeders in France, Nicaragua and Colombia. An additive linear model of the duration in days to panicle initiation (PI) and flowering time using daylength and daily changes in sunrise and sunset times was implemented. KEY RESULTS: Simultaneous with the phyllochron, the duration to PI of field crops acclimated to the mean temperature at seedling emergence within the usual range of mean cropping temperatures. A unique additive linear model combining daylength and daily changes in sunrise and sunset hours was accurately fitted for any type of response in the duration to PI to the sowing date without any temperature input. Once calibrated on a complete and an incomplete monthly sowing series at two tropical latitudes, the model accurately predicted the duration to PI of the concerned varieties from the equatorial to the temperate zone. CONCLUSIONS: Including the daily changes in sunrise and sunset times in the updated photoperiodism model largely improved its accuracy at the latitude of each experiment. More research is needed to ascertain its multi-latitudinal accuracy, especially at latitudes close to the equator.


Assuntos
Oryza , Sorghum , Aclimatação , Flores , Humanos , Fotoperíodo , Temperatura
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