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1.
J Fungi (Basel) ; 10(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667926

RESUMO

Alternaria leaf blight has recently been described as an emerging fungal disease of apple trees which is causing the significant damage in the apple-growing areas of Tianshui and Jingning, Gansu, China. In the present study, the pathogen species involved in apple leaf blight and its biological characteristics were identified, and the inhibitory activity of different botanical fungicides against the pathogen was evaluated in vitro. Four strains were isolated from the symptomatic areas of necrotic apple leaves, and initially healthy leaves showed similar symptoms to those observed in orchards after inoculation with the ABL2 isolate. The ABL2 isolate was identified as Alternaria tenuissima based on the morphological characteristics of its colonies, conidiophores, and conidia, and this was also confirmed by multi-gene sequence (ITS, OPA10-2, Alta-1, and endoPG) analysis and phylogenic analysis. The optimum temperature, pH, carbon source, and nitrogen source for the growth of A. tenuissima mycelia were 28 °C, 6-7, soluble starch, and soy flour, respectively. In addition, the botanical fungicide eugenol exhibited the highest inhibitory effect on the mycelial growth and conidia germination of A. tenuissima, and the median effective concentration (EC50) values were 0.826 and 0.755 µg/mL, respectively. The protective and curative efficacy of eugenol were 86.85% and 76.94% after inoculation in detached apple leaves at a concentration of 4 µg/mL. Our research provides new insights into the control of apple leaf blight disease by applying botanical fungicides.

2.
Environ Res ; 251(Pt 2): 118673, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493845

RESUMO

Both microplastics (MPs) and heavy metals are common soil pollutants and can interact to generate combined toxicity to soil ecosystems, but their impact on soil microbial communities (e.g., archaea and viruses) remains poorly studied. Here, metagenomic analysis was used to explore the response of soil microbiome in an agricultural soil exposed to MPs [i.e., polyethylene (PE), polystyrene (PS), and polylactic acid (PLA)] and/or Cd. Results showed that MPs had more profound effects on microbial community composition, diversity, and gene abundances when compared to Cd or their combination. Metagenomic analysis indicated that the gene taxonomic diversity and functional diversity of microbial communities varied with MPs type and dose. MPs affected the relative abundance of major microbial phyla and genera, while their coexistence with Cd influenced dominant fungi and viruses. Nitrogen-transforming and pathogenic genera, which were more sensitive to MPs variations, could serve as the indicative taxa for MPs contamination. High-dose PLA treatments (10%, w/w) not only elevated nitrogen metabolism and pathogenic genes, but also enriched copiotrophic microbes from the Proteobacteria phylum. Overall, MPs and Cd showed minimal interactions on soil microbial communities. This study highlights the microbial shifts due to co-occurring MPs and Cd, providing evidence for understanding their environmental risks.

3.
J Hazard Mater ; 459: 132142, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37515992

RESUMO

Microplastics (MPs) occur and distribute widely in agroecosystems, posing a potential threat to soil-plant systems. However, little is known about their effects on legumes and N-fixing microbes. Here, we explored the effects of high-density polyethylene (HDPE), polystyrene (PS), and polylactic acid (PLA) on the growth of peanuts and soil N-fixing bacterial communities. All MPs treatments showed no phytotoxic effects on plant biomass, and PS and PLA even increased plant height, especially at the high dose. All MPs changed soil NO3--N and NH4+-N contents and the activities of urease and FDAse. Particularly, high-dose PLA decreased soil NO3--N content by 97% and increased soil urease activity by 104%. In most cases, MPs negatively affected plant N content, and high-dose PLA had the most pronounced effects. All MPs especially PLA changed soil N-fixing bacterial community structure. Symbiotic N-fixer Rhizoboales were greatly enriched by high-dose PLA, accompanied by the emergence of root nodulation, which may represent an adaptive strategy for peanuts to overcome N deficiency caused by PLA MPs pollution. Our findings indicate that MPs can change peanut-N fixing bacteria systems in a type- and dose-dependent manner, and biodegradable MPs may have more profound consequences for N biogeochemical cycling than traditional MPs.


Assuntos
Arachis , Fabaceae , Microplásticos/toxicidade , Plásticos , Fixação de Nitrogênio , Urease , Bactérias , Poliésteres , Poliestirenos , Solo
4.
Artigo em Inglês | MEDLINE | ID: mdl-37327101

RESUMO

Multimodal sentiment analysis (MSA) is important for quickly and accurately understanding people's attitudes and opinions about an event. However, existing sentiment analysis methods suffer from the dominant contribution of text modality in the dataset; this is called text dominance. In this context, we emphasize that weakening the dominant role of text modality is important for MSA tasks. To solve the above two problems, from the perspective of datasets, we first propose the Chinese multimodal opinion-level sentiment intensity (CMOSI) dataset. Three different versions of the dataset were constructed: manually proofreading subtitles, generating subtitles using machine speech transcription, and generating subtitles using human cross-language translation. The latter two versions radically weaken the dominant role of the textual model. We randomly collected 144 real videos from the Bilibili video site and manually edited 2557 clips containing emotions from them. From the perspective of network modeling, we propose a multimodal semantic enhancement network (MSEN) based on a multiheaded attention mechanism by taking advantage of the multiple versions of the CMOSI dataset. Experiments with our proposed CMOSI show that the network performs best with the text-unweakened version of the dataset. The loss of performance is minimal on both versions of the text-weakened dataset, indicating that our network can fully exploit the latent semantics in nontext patterns. In addition, we conducted model generalization experiments with MSEN on MOSI, MOSEI, and CH-SIMS datasets, and the results show that our approach is also very competitive and has good cross-language robustness.

5.
Int J Mol Sci ; 24(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37373491

RESUMO

GDSL esterases/lipases are a subclass of lipolytic enzymes that play critical roles in plant growth and development, stress response, and pathogen defense. However, the GDSL esterase/lipase genes involved in the pathogen response of apple remain to be identified and characterized. Thus, in this study, we aimed to analyze the phenotypic difference between the resistant variety, Fuji, and susceptible variety, Gala, during infection with C. gloeosporioides, screen for anti-disease-associated proteins in Fuji leaves, and elucidate the underlying mechanisms. The results showed that GDSL esterase/lipase protein GELP1 contributed to C. gloeosporioides infection defense in apple. During C. gloeosporioides infection, GELP1 expression was significantly upregulated in Fuji. Fuji leaves exhibited a highly resistant phenotype compared with Gala leaves. The formation of infection hyphae of C. gloeosporioides was inhibited in Fuji. Moreover, recombinant His:GELP1 protein suppressed hyphal formation during infection in vitro. Transient expression in Nicotiana benthamiana showed that GELP1-eGFP localized to the endoplasmic reticulum and chloroplasts. GELP1 overexpression in GL-3 plants increased resistance to C. gloeosporioides. MdWRKY15 expression was upregulated in the transgenic lines. Notably, GELP1 transcript levels were elevated in GL-3 after salicylic acid treatment. These results suggest that GELP1 increases apple resistance to C. gloeosporioides by indirectly regulating salicylic acid biosynthesis.


Assuntos
Colletotrichum , Malus , Esterases/genética , Esterases/metabolismo , Lipase/metabolismo , Malus/genética , Malus/metabolismo , Colletotrichum/genética , Folhas de Planta/metabolismo , Ácido Salicílico/farmacologia , Doenças das Plantas/genética
6.
J Hazard Mater ; 451: 131152, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36934700

RESUMO

Both nitrogen deposition (ND) and microplastics (MPs) pose global change challenges. The effects of MPs co-existing with ND on ecosystem functions are still largely unknown. Herein, we conducted a 10-month soil incubation experiment to explore the effects of polyethylene (PE) and polylactic acid (PLA) MPs on soil multifunctionality under different ND scenarios. We found that the interactions between ND and MPs affected soil multifucntionality. FAPROTAX function prediction indicated that both ND and MPs affected C and N cycling. ND increased some C-cycling processes, such as cellulolysis, ligninolysis, and plastic degradation. MPs also showed stimulating effects on these processes, particularly in the soil with ND. ND significantly decreased the abundance of functional genes NifH, amoA, and NirK, leading to inhibited N-fixation, nitrification, and denitrification. The addition of MPs also modified N-cycling processes: 0.1% PE enriched the bacterial groups for nitrate reduction, nitrate respiration, nitrite respiration, and nitrate ammonification, and 1% PLA MPs enriched N-fixation bacteria at all ND levels. We found that ND caused lower soil pH but higher soil N, decreased bacterial diversity and richness, and changed the composition and activity of functional bacteria, which explains why ND changed soil functions and regulated the impact of MPs.


Assuntos
Microplásticos , Solo , Solo/química , Ecossistema , Plásticos , Nitrogênio/metabolismo , Nitratos , Microbiologia do Solo , Bactérias/metabolismo , Poliésteres
7.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850883

RESUMO

Movie scene event extraction is a practical task in media analysis, which aims at extracting structured events from unstructured movie scripts. However, although there have been many studies regarding open domain event extraction, there have only been a few studies focusing on movie scene event extraction. Specifically aimed at instances where different argument roles have the same characteristics in a movie scene, we propose the utilization of the correlation between different argument roles, which is beneficial for both movie scene trigger extraction (trigger identification and classification) and movie scene argument extraction (argument identification and classification) in event extraction. To model the correlation between different argument roles, we propose the superior role concept (SRC), a high-level role concept based upon the ordinary argument role. In this paper, we introduce a new movie scene event extraction model with two main features: (1) an attentive high-level argument role module to capture SRC information and (2) an SRC-based graph attention network (GAT) to fuse the argument role correlation information into semantic embeddings. To evaluate the performance of our model, we constructed a movie scene event extraction dataset named MovieSceneEvent and also conducted experiments on a widely used dataset to compare the results with other models. The experimental results show that our model outperforms competitive models, and the correlation information of argument roles helps to improve the performance of movie scene event extraction.

8.
Environ Technol ; 44(13): 1926-1935, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34882507

RESUMO

Bioreduction of Cr(VI) to Cr(III) by reducing microbes has attracted increasing concern. Here, Cr(VI) removal capacity of a Cr(VI)-resistant bacterium isolated from activated sludge was investigated. Based on its physio-biochemical attributes and 16S rDNA sequence analysis, the strain was identified as Bacillus cereus ZY-2009. It grew normally in the media containing 10-100 mg/L Cr(VI), indicating its high resistance to Cr(VI). Under the optimal conditions of pH 7.0, inoculation amount 10%, and temperature 30°C, Cr(VI) was effectively removed, with a removal rate of ∼80%. Co-existing Fe3+ and Cu2+ greatly increased Cr(VI) removal, but Cd2+ showed significant inhibition. Cr(VI) was removed mainly via enzyme-mediated bioreduction but not biosorption. Cr(VI) was reduced by different cell fractions (i.e. extracellular secretions, cytoplasm, and cell envelope), implying that Cr(VI) can be reduced both extracellularly and intracellularly. This strain can be used in the bioremediation of Cr(VI)-containing wastewater, with Fe3+ and Cu2+ as stimulators.


Assuntos
Bacillus cereus , Cromo , Biodegradação Ambiental , Esgotos/microbiologia , Oxirredução
9.
Entropy (Basel) ; 24(12)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36554248

RESUMO

Digital audio watermarking is a promising technology for copyright protection, yet its low embedding capacity remains a challenge for widespread applications. In this paper, the spread-spectrum watermarking algorithm is viewed as a communication channel, and the embedding capacity is analyzed and modeled with information theory. Following this embedding capacity model, we propose the extended-codebook spread-spectrum (ECSS) watermarking algorithm to heighten the embedding capacity. In addition, the diversity reception (DR) mechanism is adopted to optimize the proposed algorithm to obtain both high embedding capacity and strong robustness while the imperceptibility is guaranteed. We experimentally verify the effectiveness of the ECSS algorithm and the DR mechanism, evaluate the performance of the proposed algorithm against common signal processing attacks, and compare the performance with existing high-capacity algorithms. The experiments demonstrate that the proposed algorithm achieves a high embedding capacity with applicable imperceptibility and robustness.

10.
PeerJ ; 10: e12923, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530412

RESUMO

Several studies have reported the deleterious effects of excessive salt stress on Triticum aestivum L. seedlings. Seed pretreatment with exogenous salicylic acid (SA) enhances plants to tolerate salt stress. Herein, the present study aims to investigate the potential of plant-growth-promoting fungus Trichoderma longibrachiatum (TG1) to increase the plant growth and enhance the salicylic acid (SA) contents and antioxidants activity in wheat seedlings under different concentrations of salt stress. Wheat seeds were pretreated in TG1 spore suspension before exposure to different salt stresses. Compared with 0, 50, 100, 150 salt stresses, the TG1 and NaCl increased the wheat seeds germination rate, germination potential and germination index significantly; the shoot height and root length were increased by an average of 39.45% and 29.73%, respectively. Compared to NaCl stress across the four concentrations (0, 50, 100, and 150 mM), the TG1 treated wheat seedlings increased SA concentration and phenylalanine ammonia-lyase activity (PAL) by an average of 55.87% and 24.10% respectively. In addition, the TG1+NaCl-treated seedlings increased superoxide dismutase (SOD), peroxidases (POD), and catalase (CAT) activities in the shoot by an average of 47.68%, 23.68%, and 38.65% respectively compared to NaCl-stressed seedlings. Significantly, the genes, SOD, CAT, and POD were relatively up-regulated in the salt-tolerant TG1-treated seedlings at all NaCl concentrations in comparison to the control. Wheat seedlings treated with TG1+NaCl increased the transcript levels of SOD, POD and CAT by 1.35, 1.85 and 1.04-fold at 50 mM NaCl concentration, respectively, compared with 0 mM NaCl concentration. Our results indicated that seeds pretreatment with TG1 could increase endogenous SA of plants and promote seedling growth under salt stress by improving enzymatic antioxidant activities and gene expression.


Assuntos
Antioxidantes , Plântula , Antioxidantes/metabolismo , Triticum , Ácido Salicílico/farmacologia , Cloreto de Sódio/farmacologia , Estresse Salino , Peroxidases/metabolismo , Superóxido Dismutase/genética
11.
J Fungi (Basel) ; 8(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36354941

RESUMO

Brown rot caused by the pathogen of the genus Monilinia is the most destructive disease in peaches worldwide. It has seriously reduced the economic value of the peach (Prunus persica (L.) Batsch) in Nyingchi and Qamdo, Tibet, China. Monilinia fructicola, Monilia mumecola, and M. yunnanensis have been reported as the causal agents of brown rot disease on stone fruits in China. In this study, we report on the identification of M. yunnanensis in peach orchards in Nyingchi and Qamdo, Tibet. From twenty-three isolates with the same characteristics, we identified the representative single-spore isolates T8-1, T8-8, and T8-20 as M. yunnanensis and confirmed that the Tibet brown rot disease was caused by M. yunnanensis based on the morphological characteristics and molecular analyses. The phylogenetic analysis of the glyceraldehyde-3-phosphate dehydrogenase (G3PDH) and ß-tubulin (TUB2) nucleotide sequences and the multiplex PCR identification revealed that the representative isolates T8-1, T8-8, and T8-20 were more closely related to M. yunnanensis than other Monilinia species. Furthermore, the biocontrol strain of Trichoderma T6 presented significant antagonistic activity on the M. yunnanensis T8-1 isolate (T8-1) among the five Trichoderma strains. The highest inhibitory rates for Trichoderma T6 and its fermentation product against T8-1 mycelial growth were 72.13% and 68.25%, respectively. The obvious inhibition zone displayed on the colony interaction area between the colony of T8-1 isolate and Trichoderma T6 and the morphological characterization of the T8-1 hyphae were enlarged and malformed after inoculation with the Trichoderma T6 fermentation product at 20-fold dilution. Our results indicate that the strain of Trichoderma T6 could be considered as a beneficial biocontrol agent in managing brown rot of peach fruit disease.

12.
Int J Biol Macromol ; 223(Pt B): 1641-1652, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36273547

RESUMO

Endochitinase is a natural extracellular protein in Trichoderma longibrachiatum T6, which can degrade the eggshell of Heterodera avenae significantly, however the related genes that coding this protein was rarely characterized. In the present study, the endochitinase 18-5 gene (T6-Echi18-5) of T. longibrachiatum T6 was cloned and sequenced. The expression level of T6-Echi18-5 gene in T. longibrachiatum T6 was induced and increased after the H. avenae cysts inoculation. The full-length cDNA sequence of T6-Echi18-5 was 1671 bp that contained an ORF of 1275 bp, corresponding to 424 amino acids with a 45.9 kDa molecular weight. A single band of 60.04 kDa was detected and identified using SDS-PAGE and Western blot analysis after transferring the T6-Echi18-5 gene to Escherichia coli BL21 Rosetta (DE3). The concentration of purified recombinant T6-Echi18-5 protein was 1.53 mg·ml-1, and the optimal temperature and pH were 50 °C and 5.0, respectively. The eggshell and content were dissolved and exuded from 4 to10 days after treatment with the purified recombinant T6-Echi18-5 protein. The relative inhibition rate of eggs hatching was 86.79 % at 12 days after treatment. Our study demonstrated the key role of T6-Echi18-5 gene in degrading the H. avenae eggshell and inhibiting the eggs hatching.


Assuntos
Quitinases , Hypocreales , Trichoderma , Quitinases/genética , Trichoderma/metabolismo , Antinematódeos , Hypocreales/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
13.
Front Physiol ; 13: 901115, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928566

RESUMO

Aphids are one of the most common insect pests in greenhouse and field crops worldwide, causing significant crop yields and economic losses. The objective of this study was to determine the mortality, enzymatic antioxidant activity and gene expression of cabbage aphids (Brevicoryne brassicae L.) in response to Trichoderma longibrachiatum T6 (T6) at different time points from Day 1 to 7 after inoculation. Our results showed that the highest mortality of B. brassicae was observed on Day 7 at a concentration of 1 × 108 spores ml-1 (73.31%) after inoculation with T6 compared with the control on Day 7 (11.51%). The activities of the enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GPX) and glutathione S-transferase (GST) were increased by 52.98%, 44.77%, 48.26%, 49.39%, 45.13% and 39.67%, respectively on Day 3 after inoculation with T6 compared to the control. Howerver increased days post treatment (dpt) decreased the activities of SOD, POD, CAT, APX, GPX and GST enzymes by 20.79%, 21.05%, 13.75%, 20.45%, 25.38%, and 19.76% repectively on Day 7 compared to control. The transcript levels of SOD, POD, CAT, GPX, and GST genes were increased by 10.87, 9.87, 12.77, 6.22 and 4.07 respectively at Day 3 after inoculation with T6 in comparison to the control. However, the SOD, POD, CAT, GPX, and GST transcription levels decreased by 0.43, 0.44, 0.35, 0.52 and 0.47 respectively, compared to control at Day 7. Our results suggest that the T6 strain has a potential effect on the antioxidant activity and mortality of B. brassicae and therefore could be used as a natural biocontrol agent against B. brassicae in the future.

14.
Nanomaterials (Basel) ; 12(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35630987

RESUMO

To improve the extraction performance of the silica aerogel, a melamine-terephthalaldehyde polymer was used to hybridize silica aerogel, and the hybridized aerogel was coated on the surface of stainless steel wire to prepare a fiber-filled extraction tube through placing four wires into a polyetheretherketone tube. The tube was combined with high-performance liquid chromatography, then the online extraction and detection were established. Several polycyclic aromatic hydrocarbons (PAHs) were selected as the target analytes. Under the optimum extraction and desorption conditions, the limit of detection was as low as 3.0 ng L-1, and the linear range was 0.01-20.0 µg L-1. The enrichment factors of PAHs were in the range of 1724-2393. Three environmental water samples of mineral water, tap water and river water were analyzed by this method, and the recoveries that spiked at 1.0-10.0 µg L-1 were between 80.5-126%. It showed many advantages compared with other methods, such as better sensitivity, faster detection and online analysis.

15.
J Hazard Mater ; 433: 128826, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35381513

RESUMO

A 100-day soil incubation experiment was conducted to explore the effects of conventional (high-density polyethylene, HDPE) and biodegradable (polylactic acid, PLA) microplastics (MPs) and multiwall carbon nanotubes (MWCNTs) on soil geochemical properties and bacterial communities. Generally, soil pH was increased by 10% HDPE and 10% PLA, but decreased by increasing MWCNTs. Soil dissolved organic carbon content was only increased by 10% PLA. NO3--N content was significantly decreased by MPs, with a decrement of 99% by 10% PLA. Similarly, available P content was reduced by 10% MPs. The activities of urease and alkaline phosphatase were stimulated by 10% PLA, but generally inhibited by HDPE. Conversely, FDAse activity was stimulated by HDPE, but inhibited by 10% PLA, whereas invertase activity decreased with increasing MWCNTs. Overall, both MPs and MWCNTs changed soil bacterial diversity. Co-exposure to 10% MPs and MWCNTs of 1 and 10 mg/kg caused the lowest species richness and Shannon indexes. MPs especially at the 10% dose changed bacterial community composition and the associated metabolic pathways, causing the enrichment of specific taxa and functional genes. Our findings show that conventional and biodegradable MPs differently change soil geochemical properties and microbial community structure and functions, which can be further modified by co-existing MWCNTs.


Assuntos
Nanotubos de Carbono , Solo , Bactérias/genética , Microplásticos , Nanotubos de Carbono/toxicidade , Plásticos , Poliésteres , Polietileno , Solo/química , Microbiologia do Solo
16.
PLoS One ; 17(2): e0263068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35104292

RESUMO

The aim of this study was to uncover the molecular mechanism through which fungicide resistance develops in Podosphaera xanthii, a fungi that causes powdery mildew in hull-less pumpkin. Treatments of inoculated P. xanthii were carried out on leaves of hull-less pumpkin and subsequently treated with kinds of triazole fungicide for seven generations. Resistant strains of P. xanthii thus obtained were evaluated for their resistance levels. The resistance levels of the fungi to four fungicides of were high except that of the propiconazole-resistant strain, which showed moderate resistance. The F7 generations of five resistant strains thus obtained were cultured continuously for five generations without fungicide induction, and their resistance level were found to be relatively stable. The DNA of the sensitive strain and the five kinds of resistant strains were extracted by the sodium dodecyl sulfate (SDS) method and its internal transcribed spacer (ITS) region was amplified by using ITS1/ITS4 primer and specific primer F/R and they were sequenced respectively. The DNA sequence comparison of resistant and sensitive strains showed that the base pairs of tebuconazole-resistant strains and flusilazole-resistant strains were mutated, with mutation rates of 4.8% and 1.6%, respectively. The base pairs of the other three resistant strains did not change.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/genética , Farmacorresistência Fúngica/efeitos dos fármacos , Doenças das Plantas/microbiologia , Triazóis/farmacologia , Ascomicetos/fisiologia , Cucurbita/genética , Cucurbita/microbiologia , Farmacorresistência Fúngica/genética , Doenças das Plantas/genética , Folhas de Planta/genética , Folhas de Planta/microbiologia , Silanos/farmacologia
17.
J Fungi (Basel) ; 8(2)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35205867

RESUMO

Apple Valsa canker is one of the most serious diseases, having caused significant apple yield and economic loss in China. However, there is still no effective biological methods for controlling this disease. Our present study focused on the inhibitory activity and mechanisms of Trichoderma longibrachiatum (T6) fermentation on Valsa mali that causes apple Valsa canker (AVC). Our results showed that the T6 fermentation exhibited effective antifungal activity on the mycelial growth and conidia germination of V. mali, causing mycelium malformation and the hyphal disintegrating in comparison to the control. The activity of pathogenically related enzymes that are secreted from V. mali and the expression level of gene of V. mali were significantly inhibited and downregulated by treatment with T6 fermentation. In addition, the lesion area and number of pycnidia of V. mali formed on the branches were significantly reduced after treatment with the T6 fermentation through the pathogenicity test on the detached branches. Our results indicate that the possible mechanism of T6 fermentation against V. mali occurs through inhibiting its growth and reproduction, the pathogenic enzyme activity, and its related gene expression.

18.
J Hazard Mater ; 424(Pt C): 127531, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740160

RESUMO

Microplastics (MPs) are a type of emerging contaminants that pose a potential threat to global terrestrial ecosystems, including agroecosystems. In recent years, MPs in soil and their adverse effects on soil health and fertility have attracted increasing concern. Based on the current knowledge, this review begins with a summary of the occurrence and characteristics of MPs in various soil environments, and then highlights the impacts of MPs on soil physical, chemical, and microbiological properties. Data show that MPs occur widely in all surveyed soil types, such as agricultural soils, industrial soils, urban soils, and unused soils, but show variation in their abundance, type, shape, and size. In most cases, MPs can change soil physical, chemical, and microbiological properties, but the effects vary, and are dependent on polymer type, shape, dose, and size. MPs-induced changes in soil fertility and the availability of pollutants may pose a potential threat to plant performance and crop productivity and safety. Particularly, MPs influence the emission of greenhouse gases from soil, ultimately leading to uncertain consequences for global climate change. More comprehensive and in-depth studies are required to fill large knowledge gaps.


Assuntos
Microplásticos , Solo , Agricultura , Ecossistema , Plásticos/toxicidade
19.
J Hazard Mater ; 421: 126700, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34332487

RESUMO

Microplastics (MPs) are emerging contaminants in terrestrial systems that cause diverse impacts on plants. However, little is known about whether MPs especially micro-sized MPs can be accumulated and translocated in plants particularly food crops. Hereby, a hydroponic experiment was conducted to verify whether nano-sized (80 nm) and micro-sized (1 µm) fluorescently labeled polystyrene (PS) microspheres can enter rice roots and translocate to aerial parts. Plant samples were taken for detection of PS after 14 days and 40 days exposure, respectively. Both nano- and micro-sized PS microspheres were detected in roots, stems, and leaves of rice seedlings by using confocal laser scanning microscopy. Both 80 nm and 1 µm PS microspheres accumulated in the vascular systems of plant tissues, especially root stele, stem vascular bundles and leaf veins, and mostly aggregated on cell walls and in the intercellular regions. These findings imply that both nano- and micro-sized MPs could be absorbed by rice roots and subsequently translocated to aerial parts, and apoplastic transport may be the main pathway. In conclusion, rice seedlings can accumulate nano/microplastics in their roots and translocate them to aboveground tissues, thereby possibly transferring the accumulated nano/microplastics to higher trophic levels through the food chain.


Assuntos
Microplásticos , Oryza , Hidroponia , Plásticos , Poliestirenos , Plântula
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