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1.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350312

RESUMO

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Assuntos
Solo , Banco de Sementes , Paquistão , Plantas , Sementes , Ecossistema , Poaceae
2.
Bioresour Technol ; 367: 128297, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36370941

RESUMO

Herein, a Na2S promoted deep eutectic solvent (DES) was established to reduce the natural recalcitrance of moso bamboo (MB) and improve the subsequent enzymatic saccharification. It was found that the addition of Na2S (Choline chloride/Ethylene glycol/Na2S) dramatically promoted the deconstructions of lignin with highest removal of 74.67 %, but at the same time preserved glucan and hemicellulose to the maximum extent. With the fractionation, the enzymatic saccharification yield of pretreated MB can reach 100 % under the pretreatment condition of 140 °C, and lignin could be readily recovered with a high yield of 81.47 %. The proposed DES is superior to normal alkaline DES in terms of the higher lignin removal and recovery yield, carbohydrate preservation and enzymatic digestibility, which indicated Na2S as a novel and powerful reinforcer enhancing the DES fractionation efficiency.


Assuntos
Solventes Eutéticos Profundos , Lignina , Biomassa , Álcalis , Solventes , Poaceae , Hidrólise
3.
Sci Total Environ ; 856(Pt 2): 159174, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191703

RESUMO

Water provision is an important ecological function of alpine meadows on the Tibetan Plateau. Quantitative assessment of the effects of vegetation change induced by vegetation degradation and improvement on water yield (WY) in alpine meadows is urgent for rational water and grassland resources conservation and management. Previous studies mainly focused on the effects of vegetation coverage. What is less clear is how the WY of alpine meadow changes under plant community conversion caused by vegetation degradation and improvement. To test the hypotheses that lysimeter drainage (LD) decreases in the vegetation-degraded meadow and recovers in the vegetation-improved meadow, and the LD decreases as the stress tolerance of dominant strategy decreases, in situ lysimeters with intact monoliths of well-vegetated alpine meadows subjected to vegetation intact (sedge-dominated), degraded (forb-dominated) and improved (fast-growing grass-dominated) were employed, and then plant communities among treatments were compared based on the quantitative competitor, stress tolerator, and ruderal (CSR) theory. Compared to the vegetation-intact monoliths, the LD of vegetation-degraded monoliths was 59 % lower owing to the deeper roots and greater aboveground growth. The LD of vegetation-improved monoliths was 83 % higher than that of vegetation-degraded monoliths due to the shallower roots but was 25 % lower than that of vegetation-intact monoliths due to the greater aboveground growth. The LD decreased along a plant community conversion gradient in which the S-selection of the dominance strategy decreased (R2 = 0.34, P = 0.022) and the C-selection increased (R2 = 0.71, P < 0.001), likely due to the significant covariation between community-weighted CSR strategy with eco-hydrological plant and soil properties. These results indicated that the community conversion caused by vegetation degradation reduces the WY of alpine meadows, and sowing fast-growing grasses can only partly restore this function. Application of stress-tolerant plants for vegetation improvement may be more efficient in recovering the WY of degraded meadows, especially in flat meadows under humid climate.


Assuntos
Pradaria , Água , Tibet , Plantas , Solo , Poaceae
4.
Sci Total Environ ; 856(Pt 1): 158840, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36122729

RESUMO

The sea spray effect can severely influence the isotopic signature of terrestrial individuals in coastal regions. To further specify this effect, beach grass was grown in a greenhouse under controlled environmental conditions and sprayed with mineral salt solution containing different mineral salts but only traces of NaCl (group 1). Another group of plants was sprayed with salty water from the Schlei inlet and the Baltic Sea, respectively (group 2). Control plants were only sprayed with tap water. Isotope analyses were conducted on the unwashed and washed plants (δ13Ccellulose, δ18Ocellulose, δ34Stotal S, 87Sr/86Sr), soil (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr), and spray as well as irrigation water (δ18Osulfate, δ34Ssulfate, 87Sr/86Sr). Moreover, elemental analyses were performed on the water samples. The sea spray effect was visible in all isotopic systems under study. The uptake of SO42-, HCO3-, and Sr2+ directly affected plants of group 1, while plants of group 2, sprayed with salty water, additionally showed salinity stress in the case of α-cellulose and total sulfur due to biochemical reactions of the plants. Very high concentrations in HCO3- or SO42- also affected the plants' isotopic signatures. The impact of the sea spray and additional stress reactions were quantified. Our study is the first experiment creating an artificial sea spray effect in a greenhouse. This experiment for the first time enables the identification and quantification of the sea spray effect in environmental samples. The marine signature taken up by the plants and recorded by the investigated isotopic systems is apparently high and should have an impact on the isotopic fingerprints of animal consumers at the coast, as evidenced for archaeological animals from the Viking Haithabu and the early medieval Schleswig sites located close to the Baltic Sea. This result demonstrates the potential of greenhouse experiments as an isotopic predictor of the past local sea spray effect.


Assuntos
Poaceae , Enxofre , Animais , Água , Celulose , Sulfatos , Minerais
5.
J Hazard Mater ; 442: 130118, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303351

RESUMO

The molecular mechanism of arbuscular mycorrhizal fungi (AMF) in vertical flow constructed wetlands (VFCWs) for the purification of copper oxide nanoparticles (CuO-NPs) contaminated wastewater remains unclear. In this study, transcriptome analysis was used to explore the effect of AMF inoculation on the gene expression profile of Phragmites australis roots under different concentrations of CuO-NPs and/or flood stress. 551, 429 and 2281 differentially expressed genes (DEGs) were specially regulated by AMF under combined stresses of CuO-NPs and flood, single CuO-NPs stress and single flood stress, respectively. Based on the results of DEG function annotation and enrichment analyses, AMF inoculation under CuO-NPs and/or flood stress up-regulated the expression of a number of genes involved in antioxidant defense systems, cell wall biosynthesis and transporter protein, which may contribute to plant tolerance. The expression of 30 transcription factors (TFs) was up-regulated by AMF inoculation under combined stresses of CuO-NPs and flood, and 44 and 44 TFs were up-regulated under single CuO-NPs or flood condition, respectively, which may contribute to the alleviating effect of symbiosis on CuO-NPs and/or flood stress. These results provided a theoretical basis for enhancing the ecological restoration function of wetland plants for metallic nanoparticles (MNPs) by mycorrhizal technology in the future.


Assuntos
Micorrizas , Nanopartículas , Inundações , Raízes de Plantas/metabolismo , Poaceae/metabolismo , Perfilação da Expressão Gênica , Plantas , Nanopartículas/toxicidade
6.
Chemosphere ; 310: 136801, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241121

RESUMO

Fungicides containing manganese (Mn) applied to control plant diseases increase the concentration of Mn in soils, which may potentiate Mn toxicity in acid soils. Some species of wild grasses, such as those from the Pampa biome located in South America, or even those introduced into this biome, may possess different mechanisms of tolerance to excess Mn. The present study aimed to evaluate the subcellular distribution and physiological and biochemical responses of exotic and native grasses from the Pampa biome, cultivated in Mn excess. The experiment was conducted in nutrient solution in a greenhouse, in an entirely randomized design, bifactorial 4 × 4, consisting of four Mn concentrations (2 [control], 300, 600 and 900 µM) and four species (two exotic: Avena strigosa and Lolium multiflorum; and two native: Paspalum notatum and Paspalum plicatulum). At 27 days of exposure to the treatments, biomass and growth rates, leaf gas exchange with the environment, photosynthetic pigment concentrations of malondialdehyde and H2O2, antioxidant enzyme activities (SOD and POD), and subcellular distribution of Mn were evaluated. Most of the grasses showed high concentration of Mn in tissues, mainly, in the shoot. In the presence of 900 µM Mn, more than 80% of the absorbed Mn was compartmentalized in the cell walls and vacuoles of the cells. Compartmentalization of Mn excess into metabolically less active organelles is the main tolerance factor in grasses. Physiological and biochemical responses were stimulated in the presence of 300 µM Mn, while 900 µM Mn negatively affected biochemical-physiological responses of grasses. The species L. multiflorum was most sensitive to excess Mn, while P. notatum was the most tolerant.


Assuntos
Manganês , Poaceae , Antioxidantes , Ecossistema , Peróxido de Hidrogênio , Manganês/toxicidade , Solo
7.
Sci Total Environ ; 857(Pt 3): 159660, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36302420

RESUMO

A functional response-effect approach could predict how environmental changes affect ecosystem functioning. However, few studies have applied this approach to inner saline-alkaline marsh ecosystems where soil saline-alkaline, flooding/drought and nutrients stresses threat ecological functioning. To disentangle the relationships between environmental conditions and ecosystem functioning, a total of 81 plots were investigated across 22 marsh sites dominated by Phragmites australis and Bolboschoenus planiculmis in Western Songnen Plain wetlands, China. For both plant communities combined, deep flooding supported communities with higher specific leaf area (SLA), plant height and leaf nitrogen (N) content but lower leaf thickness. On the contrary, high soil salt content induced low leaf N and phosphorus (P) content, SLA and plant height. Only light acquisition-related trait, plant height and SLA, was the key traits which determined the relationships between ecosystem functioning (aboveground biomass) and saline-alkaline wetland environment. Yet indirect key traits related nutrient and water acquisition such as leaf thickness, N and P content were also found, and mediated the response of aboveground biomass through the allometric relationships with plant height or SLA. For the individual species community, only plant height was the key trait shared by P. australis and B. planiculmis, indicating the universality of plant height as a key trait for grass and sedge plants to explain how ecosystem functioning responds to abiotic factors. Hence, our findings suggest that saltmarsh plants are more inclined to alter light-acquisition traits to mediate the response of ecosystem functioning to environmental changes and that plant height is a particularly useful trait to predict plant productivity in earth system models under future environmental changes in inner saline-alkaline wetlands.


Assuntos
Ecossistema , Áreas Alagadas , Biomassa , Poaceae , Solo , Plantas
8.
Sci Total Environ ; 857(Pt 1): 159384, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36240921

RESUMO

Phytoremediation assisted by endophytic bacteria is promising to efficiently remediate cadmium (Cd) contaminated soil. Bacillus cereus BL4, isolated from Miscanthus floridulus growing around a pyrite mine, exhibited high Cd tolerance and plant growth-promoting traits and could improve Cd bioavailability in soil. As a result of the pot experiment, after inoculation with strain BL4, the fresh weight, height, and Cd accumulation of Miscanthus floridulus shoots increased by 19.08-32.26 %, 6.02-16.60 %, and 23.67 %-24.88 %, respectively, and roots increased by 49.38-56.41 %, 22.87-33.93 %, and 28.51 %-42.37 %, respectively. Under Cd stress, the chlorophyll content, photosynthetic rate, and root activity of Miscanthus floridulus increased, while the membrane permeability and malonaldehyde (MDA) content significantly decreased after the inoculation of BL4, which indicated the alleviation of the cytotoxicity of Cd. Accordingly, the glutathione (GSH) content increased, and the activities of antioxidant enzymes presented downward trends after BL4 inoculation. Cd bioavailability in soil increased after BL4 inoculation, accompanied by increases in the activities of soil enzymes (invertase, urease, alkaline phosphatase, dehydrogenase, FDA hydrolase, and catalase) as well as the richness and diversity of soil bacteria. Our findings revealed that strain BL4 might strengthen the phytoremediation of Cd by Miscanthus floridulus through its effects on plant physio-biochemistry and soil microecology, which provided a basis for the relative application to Cd-contaminated soil.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Solo/química , Bacillus cereus , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Biodegradação Ambiental , Poaceae , Raízes de Plantas/química
9.
Sci Total Environ ; 857(Pt 1): 159400, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36243070

RESUMO

This study examines the ability of the grass species Andropogon virginicus to alter the subsurface transport and redistribution of a suite of radionuclides (99Tc, 133Cs (stable analog for 135Cs and 137Cs), 237Np, 238U) with varying chemical behaviors in a Savannah River Site soil via the use of vegetated and unvegetated soil columns. After an acclimation period, a small volume of solution containing all radionuclides was introduced into the columns via Rhizon© pore water sampling tubes. Plants were grown for an additional 4 weeks before shoots were harvested, and columns were prepared for sampling. Plant presence led to decreased radionuclide release from the columns, mainly due to radionuclide specific combinations of system hydrology differences resulting from plant transpiration as well as plant uptake. For the most mobile radionuclides, 99Tc followed by 237Np, plant presence resulted in significantly different soil concentration profiles between vegetated and unvegetated columns, including notable upward migration for 237Np in columns with plants. Additionally, plant uptake of 99Tc was the greatest of all the radionuclides, with plant tissues containing an average of 44 % of the 99Tc, while plant uptake only accounted for <2 % of 237Np and <0.5 % of 133Cs and 238U in the system. Although overall plant uptake of 133Cs and 238U were similar, the majority of 133Cs taken up by plants was associated with 133Cs already available in the aqueous phase while 238U uptake was mainly associated with the solid phase, meaning that plant activity resulted in a fraction of the native 238U being mobilized and thus, made available for plant uptake. Overall, this study quantified the influence of several plant-mediated physical and biogeochemical factors that have significant influence on radionuclide mobility and transport in this complex system which can be further utilized in future system or site-specific environmental transport and risk assessment models.


Assuntos
Andropogon , Netúnio , Poluentes Radioativos do Solo , Urânio , Poluentes Radioativos do Solo/análise , Urânio/análise , Poaceae , Solo , Radioisótopos de Césio/análise , Plantas
10.
Food Chem ; 404(Pt B): 134707, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36327509

RESUMO

The effects of bamboo (Phyllostachys edulis) shoot dietary fiber (BSDF-1) on ulcerative colitis (UC) are unclear. Therefore, we performed an in vitro glycolysis study of intestinal microbiota samples, based on 16S rDNA sequencing and determining the metabolites in non-targeted colonic fecal fermentation broth. After a 48 h fermentation, the pH of the fermentation broth decreased significantly (p < 0.05) with the dextran sulfate sodium group (referred to here as the Mod group). The carbohydrate utilization rate was 26.59 %, and the total short-chain fatty acid content was 16.46 ± 0.71 mmol/L. The abundances of Alistipes and Lactobacillus increased after BDSF-1 fermentation, whereas those of Escherichia-Shigella, Enterococcus, and Proteus significantly decreased. BSDF-1 altered the levels of 17 metabolites in the Mod group after fermentation for 48 h, which reduced the cadaverine increasing induced by DSS. These results indicate that BSDF-1 can regulate the metabolism of the intestinal microbiota and the host, suggesting its use as a promising therapeutic strategy.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Animais , Camundongos , Sulfato de Dextrana , Fermentação , Fibras na Dieta/metabolismo , Colite Ulcerativa/tratamento farmacológico , Colo/metabolismo , Poaceae , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
11.
Environ Res ; 216(Pt 1): 114451, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183789

RESUMO

The composite pollution by Cr(VI) and p-chlorophenol (4-CP) has high toxicity and harms water safety. However, research on the effective removal of Cr(VI) and 4-CP composite-polluted wastewater (C&P) and efficient synchronous electricity generation with reclaimed resources is limited. In this study, a downflow Leersia hexandra constructed wetland-microbial fuel cell (DLCW-MFC) was builded to treat C&P, as well as wastewater singularly polluted by Cr(VI) (SC) and 4-CP (SP), respectively, to reveal the mechanism by which DLCW-MFC treats C&P and synchronously generates electricity. The results demonstrate that the cathode layer had a stronger removal effect on pollutants than the middle layer and anode zone layer. Moreover, SC and SP had stronger pollutant removal effects than C&P. Cr(VI) had more competitive with electrons than 4-CP, and they had a synergistic effect on efficient electricity generation. The L.hexandra in SC and SP had a better growth state and lower Cr enrichment concentration than that in C&P. Cr existed in the DLCW-MFC mainly in the form of Cr(III). Gas chromatography-mass spectrometry was used to investigate the degradation pathway of 4-CP in C&P, and indicated that Phenol, 2,4-bis(1,1-dimethylethyl)- and benzoic acid compounds were the main intermediates formed at the cathode, and further mineralized to form medium-long-chain organic compounds to form CO2. The microbial community distribution results revealed that Simplicispira, Cloacibacterium, and Rhizobium are associated with Cr(VI) removal and 4-CP degradation, and were found to be rich in the cathode of C&P. The anode of C&P was found to have more Acinetobacter (1.34%) and Spirochaeta (4.83%) than SC and SP, and the total relative abundance of electricigens at the anode of C&P (7.46%) was higher than that at the anodes of SC and SP. This study can provide a theoretical foundation for the DLCW-MFC to treat heavy metal and chlorophenol composite-polluted wastewater and synchronously generate electricity.


Assuntos
Fontes de Energia Bioelétrica , Clorofenóis , Áreas Alagadas , Águas Residuárias/química , Eletricidade , Poaceae
12.
Sci Total Environ ; 857(Pt 1): 159179, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36191722

RESUMO

Grasslands cover a large proportion of global agricultural landmass used to feed herbivores and ruminants and link the environment to the food chain via animals onto humans. However, most scientific studies of antimicrobial resistance and microbiomes at the environmental - animal nexus have focused on soil or vegetables rather than grasslands. Based on previous microbiome phyllosphere-soil studies we hypothesised that the microbiome and resistomes across soil and grass would have a core of shared taxa and antimicrobial resistance genes (ARGs), but that in addition each would also have a minority of unique signatures. Our data indicated grass contained a wider variety and higher relative abundance of ARGs and mobile genetic elements (MGEs) than soil with or without slurry amendments. The microbiomes of soil and grass were similar in content but varied in the composition proportionality. While there were commonalities across many of the ARGs present in soil and on grass their correlations with MGEs and bacteria differed, suggesting a source other than soil is also relevant for the resistome of grass. The variations in the relative abundances of ARGs in soil and on grass also indicated that either the MGEs or the bacteria carrying the ARGs comprised a higher relative abundance on grass than in soil. We conclude that while soil may be a source of some of these genes it cannot be the source for all ARGs and MGEs. Our data identifies grass as a more diverse and abundant reservoir of ARGs and MGEs in the environment than soil, which is significant to human and animal health when viewed in the context of grazing food animals.


Assuntos
Microbiota , Solo , Animais , Humanos , Antibacterianos/farmacologia , Poaceae , Microbiologia do Solo , Genes Bacterianos , Farmacorresistência Bacteriana , Bactérias
13.
BMC Plant Biol ; 22(1): 525, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36372890

RESUMO

BACKGROUND: The study presents results of research on the evolution of plastid genomes in Stipa L. which is a large genus of the Poaceae family, comprising species diverse in terms of geographic distribution, growing under highly variated habitat conditions. Complete plastome sequences of 43 taxa from Stipeae and Ampelodesmae tribes were analyzed for the variability of the coding regions against the background of phylogenetic relationships within the genus Stipa. The research hypothesis put forward in our research was that some of coding regions are affected by a selection pressure differentiated between individual phylogenetic lines of Stipa, potentially reducing the phylogenetic informativeness of these CDS. The study aimed to answer the question, which genes evolve in Stipa most rapidly and what kind of changes in the properties of encoded amino acids this entails. Another goal of this research was to find out whether individual genes are affected by positive selection and finally, whether selective pressure is uniform within the genus or does it vary between particular evolutionary lines within the genus. RESULTS: Results of our study proved the presence of selective pressure in 11 genes: ccsA, matK, ndhC, ndhF, ndhK, rbcL, rpoA rpoC1, rpoC2, rps8 and rps11. For the first time the effect of positive selection on the rps8, rps11, and ndhK genes was documented in grasses. The varied pace of evolution, different intensity and effects of selective pressure have been demonstrated between particular phylogenetic lines of the genus tested. CONCLUSIONS: Positive selection in plastid genome in Stipa mostly affects photosynthetic genes. The potential strongest adaptive pressure was observed in the rbcL gene, especially in the oldest evolutionary group comprising Central Asian high-mountain species: S. basiplumosa, S. klimesii, S. penicillata and S. purpurea, where adaptive pressure probably affected the amino acids directly related to the efficiency of CO2 assimilation.


Assuntos
Genomas de Plastídeos , Poaceae , Poaceae/genética , Filogenia , Genomas de Plastídeos/genética , Fases de Leitura Aberta , Aminoácidos , Evolução Molecular
14.
Sci Rep ; 12(1): 19580, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379963

RESUMO

Site-specific treatment of weeds in agricultural landscapes has been gaining importance in recent years due to economic savings and minimal impact on the environment. Different detection methods have been developed and tested for precision weed management systems, but recent developments in neural networks have offered great prospects. However, a major limitation with the neural network models is the requirement of high volumes of data for training. The current study aims at exploring an alternative approach to the use of real images to address this issue. In this study, synthetic images were generated with various strategies using plant instances clipped from UAV-borne real images. In addition, the Generative Adversarial Networks (GAN) technique was used to generate fake plant instances which were used in generating synthetic images. These images were used to train a powerful convolutional neural network (CNN) known as "Mask R-CNN" for weed detection and segmentation in a transfer learning mode. The study was conducted on morningglories (MG) and grass weeds (Grass) infested in cotton. The biomass for individual weeds was also collected in the field for biomass modeling using detection and segmentation results derived from model inference. Results showed a comparable performance between the real plant-based synthetic image (mean average precision for mask-mAPm: 0.60; mean average precision for bounding box-mAPb: 0.64) and real image datasets (mAPm: 0.80; mAPb: 0.81). However, the mixed dataset (real image  + real plant instance-based synthetic image dataset) resulted in no performance gain for segmentation mask whereas a very small performance gain for bounding box (mAPm: 0.80; mAPb: 0.83). Around 40-50 plant instances were sufficient for generating synthetic images that resulted in optimal performance. Row orientation of cotton in the synthetic images was beneficial compared to random-orientation. Synthetic images generated with automatically-clipped plant instances performed similarly to the ones generated with manually-clipped instances. Generative Adversarial Networks-derived fake plant instances-based synthetic images did not perform as effectively as real plant instance-based synthetic images. The canopy mask area predicted weed biomass better than bounding box area with R2 values of 0.66 and 0.46 for MG and Grass, respectively. The findings of this study offer valuable insights for guiding future endeavors oriented towards using synthetic images for weed detection and segmentation, and biomass estimation in row crops.


Assuntos
Aprendizado Profundo , Biomassa , Redes Neurais de Computação , Plantas Daninhas , Produtos Agrícolas , Poaceae , Gossypium , Processamento de Imagem Assistida por Computador/métodos
15.
PLoS One ; 17(11): e0277341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36383625

RESUMO

Mast seeding and associated events in Melocanna baccifera, the largest fruit producing bamboo, is an enigma. So far there are no comprehensive accounts on its flowering phenology, fruiting dynamics and animal interactions. In this study, spanning over 13 years (2009 to 2022), we observed eight M. baccifera clumps in JNTBGRI Bambusetum from flowering initiation, fruiting to eventual death. Flowering phenology, floral characteristics, floret types, breeding system, bee visitation, pollination, fruit production and predators were recorded; predation patterns were correlated with fruit chemistry. Flowering duration of clumps ranged from 20 (March 2009-October 2010) to 120 (September 2012-August 2022) months. Bisexual florets are dichogamous and protogynous; and female duration (22-72 h) is many times higher than male duration (2-6 h). The highest ever fruit production for an individual bamboo clump (456.67 Kg) was recorded. Of the total fallen fruits (38371), 38.11% were predated, 43.80% good fruits (no predator hits) and 18.09% immature fruits. A positive correlation between reward (fruits) versus predation was observed, especially in short intervals of high fruit production. Pollen predators (Apis cerana indica, Halictus taprabonae, Braunsapis cupulifera, Trigona iridipennis), fruit predators, ranging from arthropods to mammals, viz., millipede (Spinotarsus colosseus), slug (Mariaella dussumieri), snails (Cryptozona bistrialis, Macrochlamys sp.), borers (Achroia grisella, Blattella germanica), mammals (monkeys Macaca radiata, rats Rattus rattus, porcupine Hystrix indica, wild boar Sus scrofa, palm civet Paradoxurus hermaphroditus), seedling predators (rabbit Lepus nigricollis, deer Axis axis), and insect/pest predators (ants Crematogaster biroi, Oecophylla smaragdina, mantis Euchomenella indica) were identified. Fruit predation is linked to its age and chemistry. Apart from new insights on flowering phenology, breeding system, pollination and fruiting dynamics, this study demonstrates the vibrant interaction between M. baccifera flowers/fruits and visitors/predators, and provides significant leads towards elucidating the cause of rat multiplication and other events associated with its gregarious flowering.


Assuntos
Cervos , Frutas , Feminino , Masculino , Animais , Abelhas , Ratos , Coelhos , Melhoramento Vegetal , Flores , Polinização , Poaceae
16.
BMJ Open ; 12(11): e066851, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414301

RESUMO

OBJECTIVES: We aim to establish daily risk estimates of the relationships between grass, tree and weed pollen and asthma health outcomes. DESIGN: Time series regression analysis of exposure and health outcomes using interaction by month to determine risk estimates all year round. SETTING: Metropolitan Adelaide, South Australia. PARTICIPANTS: Health outcomes for asthma are based on 15 years of hospital admissions, 13 years emergency presentations and ambulance callouts. In adults (≥18 years), there were 10 381 hospitalisations, 26 098 emergency department (ED) presentations and 11 799 ambulance callouts and in children (0-17 years), 22 114, 39 813 and 3774, respectively. OUTCOME MEASURES: The cumulative effect of 7 day lags was calculated as the sum of the coefficients and reported as incidence rate ratio (IRR) related to an increase in 10 grains of pollen/m3. RESULTS: In relation to grass pollen, children and adults were disparate in their timing of health effects. Asthma outcomes in children were positively related to grass pollen in May, and for adults in October. Positive associations with weed pollen in children was seen from February to May across all health outcomes. For adults, weed pollen-related health outcomes were restricted to February. Adults were not affected by tree pollen, while children's asthma morbidity was associated with tree pollen in August and September. In children, IRRs ranged from 1.14 (95% CI 1.06 to 1.21) for ED presentations for tree pollen in August to 1.98 (95% CI 1.06 to 3.72) for weed pollen in February. In adults, IRRs ranged from 1.28 (95% CI 1.01 to 1.62) for weed pollen in February to 1.31 (95% CI 1.08 to 1.57) for grass pollen in October. CONCLUSION: Monthly risk assessment indicated that most pollen-related asthma health outcomes in children occur in the colder part of the year, while adults are affected in the warm season. The findings indicate a need for year-round pollen monitoring and related health campaigns to provide effective public health prevention.


Assuntos
Asma , Rinite Alérgica Sazonal , Criança , Adulto , Humanos , Poaceae , Árvores , Austrália do Sul/epidemiologia , Fatores de Tempo , Pólen/efeitos adversos , Asma/epidemiologia , Asma/etiologia , Análise de Regressão , Avaliação de Resultados em Cuidados de Saúde
17.
PLoS One ; 17(11): e0277091, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36322593

RESUMO

The use of multispecies swards on livestock farms is growing due to the wide range of benefits they bring, such as improved biomass yield and animal performance. Preferential uptake of micronutrients by some plant species means the inclusion of legumes and forbs in grass-dominated pasture swards could improve micronutrient provision to livestock via careful species selection. However, although soil properties affect plant micronutrient concentrations, it is unknown whether choosing 'best-performing' species, in terms of their micronutrient content, needs to be soil-specific or whether the recommendations can be more generic. To address this question, we carried out an experiment with 15 common grass, forb and legume species grown on four soils for five weeks in a controlled environment. The soils were chosen to have contrasting properties such as texture, organic matter content and micronutrient concentrations. The effect of soil pH was tested on two soils (pH 5.4 and 7.4) chosen to minimise other confounding variables. Yield was significantly affected by soil properties and there was a significant interaction with botanical group but not species within a botanical group (grass, forb or legume). There were differences between botanical groups and between species in both their micronutrient concentrations and total uptake. Micronutrient herbage concentrations often, but not always, reflected soil micronutrient concentrations. There were soil-botanical group interactions for micronutrient concentration and uptake by plants, but the interaction between plant species (within a botanical group) and soil was significant only for forbs, and predominantly occurred when considering micronutrient uptake rather than concentration. Generally, plants had higher yields and micronutrient contents at pH 5.4 than 7.4. Forbs tended to have higher concentrations of micronutrients than other botanical groups and the effect of soil on micronutrient uptake was only significant for forbs.


Assuntos
Fabaceae , Oligoelementos , Animais , Solo/química , Micronutrientes , Poaceae/química , Plantas
18.
Microbiome ; 10(1): 186, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329505

RESUMO

BACKGROUND: Phytoremediation is a potentially cost-effective way to remediate highly contaminated mine tailing sites. However, nutrient limitations, especially the deficiency of nitrogen (N), can hinder the growth of plants and impair the phytoremediation of mine tailings. Nevertheless, pioneer plants can successfully colonize mine tailings and exhibit potential for tailing phytoremediation. Diazotrophs, especially diazotrophic endophytes, can promote the growth of their host plants. This was tested in a mine-tailing habitat by a combination of field sampling, DNA-stable isotope probing (SIP) analysis, and pot experiments. RESULTS: Bacteria belonging to the genera Herbaspirillum, Rhizobium, Devosia, Pseudomonas, Microbacterium, and Delftia are crucial endophytes for Chinese silvergrass (Miscanthus sinensis) grown in the tailing, the model pioneer plant selected in this study. Further, DNA-SIP using 15N2 identified Pseudomonas, Rhizobium, and Exiguobacterium as putative diazotrophic endophytes of M. sinensis. Metagenomic-binning suggested that these bacteria contained essential genes for nitrogen fixation and plant growth promotion. Finally, two diazotrophic endophytes Rhizobium sp. G-14 and Pseudomonas sp. Y-5 were isolated from M. sinensis. Inoculation of another pioneer plant in mine tailings, Bidens pilosa, with diazotrophic endophytes resulted in successful plant colonization, significantly increased nitrogen fixation activity, and promotion of plant growth. CONCLUSIONS: This study indicated that diazotrophic endophytes have the potential to promote the growth of pioneer plant B. pilosa in mine tailings. Video Abstract.


Assuntos
Endófitos , Poaceae , Poaceae/microbiologia , Fixação de Nitrogênio , Bactérias , Plantas/genética , Pseudomonas/genética , China , DNA , Raízes de Plantas/microbiologia
19.
BMC Ecol Evol ; 22(1): 130, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335298

RESUMO

BACKGROUND: Fairy rings occur in diverse global biomes; however, there is a critical knowledge gap regarding drivers of fairy rings in grassland ecosystems. Grassland fairy rings are characterized belowground by an expanding mycelial front and aboveground by vigorous vegetation rings that develop concentrically with each growing season. We evaluated fairy ring dynamics in a field study conducted in semiarid grasslands to elucidate above- and belowground interactions driving distinct vegetation patterns. We followed this initial field investigation with a complementary greenhouse experiment, using soils collected from specific fairy ring zones (inside, ring-edge, outside) to examine plant-soil-microbial interactions under controlled conditions. We selected Leymus chinensis (a dominant grass) as our model plant species to assess the role of diverse fairy ring microbial communities on plant growth and nutrition. RESULTS: In our field study, plants on the ring-edge produced greater shoot biomass with higher concentrations of N and P, compared to plants inside the ring or adjacent (outside) controls. Soil microbial community biomarkers indicate shifts in relative microbial biomass as fairy rings expand. Inside the ring, plant roots showed greater damage from pathogenic fungi, compared to outside or ring-edge. Our greenhouse experiment confirmed that inoculation with live ring-edge soil generally promoted plant growth but decreased shoot P concentration. Inoculation with soil collected from inside the ring increased root pathogen infection and reduced shoot biomass. CONCLUSION: We propose that soil microbial activity within ring-edges promotes plant growth via mobilization of plant-available P or directed stimulation. However, as the ring expands, L. chinensis at the leading edge may increase pathogen accumulation, resulting in reduced growth at the center of the ring in subsequent growing seasons. Our results provide new insights into the plant-soil-microbial dynamics of fairy rings in grasslands, helping to elucidate these mysterious vegetation patterns.


Assuntos
Microbiota , Solo , Pradaria , Poaceae , Microbiologia do Solo , Plantas
20.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361880

RESUMO

Soil cadmium (Cd) pollution is a serious environmental problem imperiling food safety and human health. The endophyte Epichloë gansuensis can improve the tolerance of Achnatherum inebrians to Cd stress. However, it is still unknown whether and how the endophyte helps host plants build up a specific bacterial community when challenged by CdCl2. In this study, the responses of the structure and function of bacterial community and root exudates of E+ (E. gansuensis infected) and E- (E. gansuensis uninfected) plants to Cd stress were investigated. Analysis of bacterial community structure indicated that the rhizosphere bacterial community predominated over the root endosphere bacterial community in enhancing the resistance of CdCl2 in a host mediated by E. gansuensis. E+ plant strengthened the interspecific cooperation of rhizosphere bacterial species. Moreover, the analysis of root exudates demonstrated E. gansuensis and increased the contents of organic acids and amino acids under Cd stress, and most root exudates were significantly correlated with rhizosphere bacteria. These results suggested that E. gansuensis employed a specific strategy to recruit distinct rhizosphere bacterial species and relevant functions by affecting root exudates to improve the tolerance of the host to Cd stress. This study provides a firm foundation for the potential application of symbionts in improving phytostabilization efficiency.


Assuntos
Cádmio , Epichloe , Humanos , Cádmio/metabolismo , Rizosfera , Poaceae , Endófitos/fisiologia , Bactérias , Sementes , Exsudatos e Transudatos , Raízes de Plantas/metabolismo
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