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1.
BMC Microbiol ; 24(1): 371, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342079

RESUMO

The soybean cyst nematode (SCN, Heterodera glycines) is the most yield-limiting pathogen in soybeans worldwide. Using chemical pesticides to control this disease is harmful to human and environment. It is urgent to develop environment-friendly nematicides. The aim of this study was to discover novel biocontrol agents on H. glycines control and soybean growth under greenhouse and field conditions Eight Bacillus strains were isolated from soil rhizosphere soils and the stability and efficiency of H. glycines was assessed in greenhouse and field experiments in 2021 and 2022. In particular, the Ba2-6 strain had the highest potential, because it was a biocontrol agent against H. glycines shown to cause 93.85% juvenile mortality. Furthermore, strains Ba 1-7, Ba2-4, and Ba2-6 effectively reduced the number of females and improved the soybean seed number per plant. Based on their morphological, physiological, biochemical and molecular (16 S rRNA) characteristics, the three strains were identified as B. aryabhattai (Ba1-7), B. megatherium (Ba2-4), and B. halotolerans (Ba2-6). The ability of Ba2-6 to induce systemic resistance to H. glycines in soybeans was investigated by the split-root system and real-time quantitative PCR experiments. The results indicated that the Ba2-6 strain induced systemic resistance to suppress the penetration of H. glycines, and enhanced gene expression of PR1, PR3a, PR5, and NPR1-2, involved in the salicylic acid and jasmonic acid pathways. The study suggests that the strains of B. aryabhattai Ba1-7, B. megatherium Ba2-4, and B. halotolerans Ba2-6 can be considered as effective biocontrol agents to control H. glycines. Further, B. halotolerans Ba2-6 not only promotes soybean growth but also enhances resistance to H. glycines by regulating defense-related gene expression and inducing systemic resistance in soybean.


Assuntos
Bacillus , Glycine max , Doenças das Plantas , Rizosfera , Microbiologia do Solo , Tylenchoidea , Glycine max/parasitologia , Glycine max/microbiologia , Animais , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/fisiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Bacillus/genética , Bacillus/fisiologia , Bacillus/metabolismo , Controle Biológico de Vetores/métodos , Filogenia , Feminino
2.
Crit Rev Biotechnol ; : 1-19, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004515

RESUMO

Filamentous plant pathogens, including fungi and oomycetes, pose significant threats to cultivated crops, impacting agricultural productivity, quality and sustainability. Traditionally, disease control heavily relied on fungicides, but concerns about their negative impacts motivated stakeholders and government agencies to seek alternative solutions. Biocontrol agents (BCAs) have been developed as promising alternatives to minimize fungicide use. However, BCAs often exhibit inconsistent performances, undermining their efficacy as plant protection alternatives. The eukaryotic cell wall of plants and filamentous pathogens contributes significantly to their interaction with the environment and competitors. This highly adaptable and modular carbohydrate armor serves as the primary interface for communication, and the intricate interplay within this compartment is often mediated by carbohydrate-active enzymes (CAZymes) responsible for cell wall degradation and remodeling. These processes play a crucial role in the pathogenesis of plant diseases and contribute significantly to establishing both beneficial and detrimental microbiota. This review explores the interplay between cell wall dynamics and glycan interactions in the phytobiome scenario, providing holistic insights for efficiently exploiting microbial traits potentially involved in plant disease mitigation. Within this framework, the incorporation of glycobiology-related functional traits into the resident phytobiome can significantly enhance the plant's resilience to biotic stresses. Therefore, in the rational engineering of future beneficial consortia, it is imperative to recognize and leverage the understanding of cell wall interactions and the role of the glycome as an essential tool for the effective management of plant diseases.

3.
Appl Microbiol Biotechnol ; 108(1): 370, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861018

RESUMO

Members of the genus Lysinibacillus attract attention for their mosquitocidal, bioremediation, and plant growth-promoting abilities. Despite this interest, comprehensive studies focusing on genomic traits governing plant growth and stress resilience in this genus using whole-genome sequencing are still scarce. Therefore, we sequenced and compared the genomes of three endophytic Lysinibacillus irui strains isolated from Canary Island date palms with the ex-type strain IRB4-01. Overall, the genomes of these strains consist of a circular chromosome with an average size of 4.6 Mb and a GC content of 37.2%. Comparative analysis identified conserved gene clusters within the core genome involved in iron acquisition, phosphate solubilization, indole-3-acetic acid biosynthesis, and volatile compounds. In addition, genome analysis revealed the presence of genes encoding carbohydrate-active enzymes, and proteins that confer resistance to oxidative, osmotic, and salinity stresses. Furthermore, pathways of putative novel bacteriocins were identified in all genomes. This illustrates possible common plant growth-promoting traits shared among all strains of L. irui. Our findings highlight a rich repertoire of genes associated with plant lifestyles, suggesting significant potential for developing inoculants to enhance plant growth and resilience. This study is the first to provide insights into the overall genomic signatures and mechanisms of plant growth promotion and biocontrol in the genus Lysinibacillus. KEY POINTS: • Pioneer study in elucidating plant growth promoting in L. irui through comparative genomics. • Genome mining identified biosynthetic pathways of putative novel bacteriocins. • Future research directions to develop L. irui-based biofertilizers for sustainable agriculture.


Assuntos
Bacillaceae , Genoma Bacteriano , Genômica , Bacillaceae/genética , Bacillaceae/metabolismo , Composição de Bases , Família Multigênica , Arecaceae/microbiologia , Desenvolvimento Vegetal , Sequenciamento Completo do Genoma , Bacteriocinas/genética , Bacteriocinas/metabolismo , Bacteriocinas/biossíntese , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Estresse Fisiológico
4.
Molecules ; 29(16)2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39202859

RESUMO

Molds pose a severe challenge to agriculture because they cause very large crop losses. For this reason, synthetic fungicides have been used for a long time. Without adequate protection against pests and various pathogens, crop losses could be as high as 30-40%. However, concerns mainly about the environmental impact of synthetic antifungals and human health risk have prompted a search for natural alternatives. But do natural remedies only have advantages? This article reviews the current state of knowledge on the use of antifungal substances in agriculture to protect seeds against phytopathogens. The advantages and disadvantages of using both synthetic and natural fungicides to protect cereal grains were discussed, indicating specific examples and mechanisms of action. The possibilities of an integrated control approach, combining cultural, biological, and chemical methods are described, constituting a holistic strategy for sustainable mold management in the grain industry.


Assuntos
Antifúngicos , Grão Comestível , Fungicidas Industriais , Grão Comestível/química , Grão Comestível/microbiologia , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Antifúngicos/farmacologia , Antifúngicos/química , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Fungos/efeitos dos fármacos , Humanos , Agricultura/métodos
5.
Indian J Microbiol ; 64(2): 343-366, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39011025

RESUMO

Uncontrolled usage of chemical fertilizers, climate change due to global warming, and the ever-increasing demand for food have necessitated sustainable agricultural practices. Removal of ever-increasing environmental pollutants, treatment of life-threatening diseases, and control of drug-resistant pathogens are also the need of the present time to maintain the health and hygiene of nature, as well as human beings. Research on plant-microbe interactions is paving the way to ameliorate all these sustainably. Diverse bacterial endophytes inhabiting the internal tissues of different parts of the plants promote the growth and development of their hosts by different mechanisms, such as through nutrient acquisition, phytohormone production and modulation, protection from biotic or abiotic challenges, assisting in flowering and root development, etc. Notwithstanding, efficient exploitation of endophytes in human welfare is hindered due to scarce knowledge of the molecular aspects of their interactions, community dynamics, in-planta activities, and their actual functional potential. Modern "-omics-based" technologies and genetic manipulation tools have empowered scientists to explore the diversity, dynamics, roles, and functional potential of endophytes, ultimately empowering humans to better use them in sustainable agricultural practices, especially in future harsh environmental conditions. In this review, we have discussed the diversity of bacterial endophytes, factors (biotic as well as abiotic) affecting their diversity, and their various plant growth-promoting activities. Recent developments and technological advancements for future research, such as "-omics-based" technologies, genetic engineering, genome editing, and genome engineering tools, targeting optimal utilization of the endophytes in sustainable agricultural practices, or other purposes, have also been discussed.

6.
BMC Plant Biol ; 23(1): 435, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723471

RESUMO

BACKGROUND: During Fritillaria thunbergii planting, pests and diseases usually invade the plant, resulting in reduced yield and quality. Previous studies have demonstrated that using biocontrol agents can effectively control grubs and affect the steroid alkaloids content in F. thunbergii. However, the molecular regulatory mechanisms underlying the differences in the accumulation of steroid alkaloids in response to biocontrol agents remain unclear. RESULTS: Combined transcriptomic and metabolic analyses were performed by treating the bulbs of F. thunbergii treated with biocontrol agents during planting. Otherwise, 48 alkaloids including 32 steroid alkaloids, 6 indole alkaloids, 2 scopolamine-type alkaloids, 1 isoquinoline alkaloid, 1 furoquinoline alkaloid, and 6 other alkaloids were identified. The content of steroidal alkaloids particularly peimine, peiminine, and veratramine, increased significantly in the group treated with the biocontrol agents. Transcriptome sequencing identified 929 differential genes using biocontrol agents, including 589 upregulated and 340 downregulated genes. Putative biosynthesis networks of steroid alkaloids have been established and combined with differentially expressed structural unigenes, such as acetyl-CoA C-acetyl-transferase, acelyl-CoAC-acetyltransferase3-hydroxy-3-methylglutaryl-coenzyme A synthase, 1-deoxy-D-xylulose-5-phosphate reductor-isomerase, 2-C-methyl-D-erythritol-4-phosphate cytidylyltransferase and 4-hydroxy-3-methylbut-2-enyl diphosphate reductase. In addition, biological processes such as amino acid accumulation and oxidative phosphorylation were predicted to be related to the synthesis of steroid alkaloids. Cytochrome P450 enzymes also play crucial roles in the steroid alkaloid synthesis. The transcription factor families MYB and bHLH were significantly upregulated after using biocontrol agents. CONCLUSIONS: Biocontrol agents increased the steroid alkaloids accumulation of steroid alkaloids by affecting key enzymes in the steroid alkaloid synthesis pathway, biological processes of oxidative phosphorylation and amino acid synthesis, cytochrome P450 enzymes, and transcription factors. This study revealed the mechanism underlying the difference in steroidal alkaloids in F. thunbergii after using biocontrol agents, laying the groundwork for future industrial production of steroid alkaloids and ecological planting of medicinal materials in the future.


Assuntos
Alcaloides , Fritillaria , Transcriptoma , Perfilação da Expressão Gênica , Aminoácidos
7.
BMC Microbiol ; 23(1): 218, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573330

RESUMO

BACKGROUND: The most serious challenges in medicinal 'Sanghuang' mushroom production are the fungal diseases caused by various molds. Application of biological agents has been regarded as a potential crop disease management strategy. Here, the soil microbiome associated with 'Sanghuang' mushroom affected by fungal diseases grown under field cultivation (FC) and hanging cultivation (HC) was characterized using culture-dependent and culture-independent methods. RESULTS: A total of 12,525 operational taxonomic units (OTUs) and 168 pure cultures were obtained using high-throughput sequencing and a culture-dependent method, respectively. From high-throughput sequencing, we found that HC samples had more OTUs, higher α-diversity, and greater microbial community complexity than FC samples. Analysis of ß-diversity divided the soil microbes into two groups according to cultivation mode. Basidiomycota (48.6%) and Ascomycota (46.5%) were the two dominant fungal phyla in FC samples, with the representative genera Trichoderma (56.3%), Coprinellus (29.4%) and Discosia (4.8%), while only the phylum Ascomycota (84.5%) was predominant in HC samples, with the representative genera Discosia (34.0%), Trichoderma (30.2%), Penicillium (14.9%), and Aspergillus (7.8%). Notably, Trichoderma was predominant in both the culture-independent and culture-dependent analyses, with Trichoderma sp. FZ0005 showing high host pathogenicity. Among the 87 culturable bacteria, 15 exhibited varying extents of antifungal activity against Trichoderma sp. FZ0005, with three strains of Bacillus spp. (HX0037, HX0016, and HX0039) showing outstanding antifungal capacity. CONCLUSIONS: Overall, our results suggest that Trichoderma is the major causal agent of 'Sanghuang' fungal diseases and that Bacillus strains may be used as biocontrol agents in 'Sanghuang' cultivation.


Assuntos
Agaricales , Ascomicetos , Bacillus , Microbiota , Micoses , Trichoderma , Agaricales/genética , Solo/química , Antifúngicos , Microbiota/genética , Trichoderma/genética , Microbiologia do Solo
8.
Arch Microbiol ; 205(8): 288, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464076

RESUMO

The agriculture is extremely important for the life of human beings. Therefore, it is needed to control the enemies that destroy vast areas of crops causing great economic losses. Chemical pesticides were the option for many decades, but the damage that they cause to environment and human health led to the idea of changing the use of these for more sustainable options such as biopesticides as a biological control. Among microbial pesticides, Serratia species have been found as suitable options to apply against several pests or pathogens. Serratia species produce a wide range of secondary metabolites with several biological activities such as antifungal, antibacterial, and pesticides which can be used in sustainable agriculture. It has been reported that several Serratia species are able to suppress some crop diseases caused by Fusarium oxysporum, Rhizoctonia solani, Phytophthora parasitica, Sclerotinia sclerotiorum, Verticillium dahlia, and Phytophthora capsici among others. Therefore, they have been used as biocontrol agents in agriculture. In this review, we summarized the genus Serratia describing its history and development and the metabolites it secretes, which are responsible for their antibacterial and antifungal activity. We have analyzed the insecticide capacity of several Serratia species as well antifungal properties of Serratia species against most important crops' pathogens. In conclusion, the use of Serratia as a biological control agent against plant pathogens can be a good option for a sustainable agriculture. More work is needed to assess the safety of the isolated new strains and their effectiveness against pathogens in in vivo conditions.


Assuntos
Inseticidas , Praguicidas , Humanos , Antifúngicos/metabolismo , Serratia , Antibacterianos , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
9.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086610

RESUMO

AIMS: Aspergillus fungi are common members of the soil microbiota. Some physiological and structural characteristics of Aspergillus species make them important participants in soil ecological processes. In this study, we aimed to evaluate the impact of 2,4-diacetylphloroglucinol (2,4-DAPG), a common metabolite of soil and rhizosphere bacteria, on the physiology of Aspergillus fumigatus. METHODS AND RESULTS: Integrated analysis using microscopy, spectrophotometry, and liquid chromatography showed the following effects of 2,4-DAPG on Aspergillus physiology. It was found that A. fumigatus in the biofilm state is resistant to high concentrations of 2,4-DAPG. However, experimental exposure led to a depletion of the extracellular polymeric substance, changes in the structure of the cell wall of the mycelium (increase in the content of α- and ß-glucans, chitin, and ergosterol), and conidia (decrease in the content of DHN-melanin). 2,4-DAPG significantly reduced the production of mycotoxins (gliotoxin and fumagillin) but increased the secretion of proteases and galactosaminogalactan. CONCLUSIONS: Overall, the data obtained suggest that 2,4-DAPG-producing Pseudomonas bacteria are unlikely to directly eliminate A. fumigatus fungi, as they exhibit a high level of resistance when in the biofilm state. However, at low concentrations, 2,4-DAPG significantly alters the physiology of aspergilli, potentially reducing the adaptive and competitive capabilities of these fungi.


Assuntos
Aspergillus fumigatus , Matriz Extracelular de Substâncias Poliméricas , Humanos , Aspergillus fumigatus/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Floroglucinol/farmacologia , Floroglucinol/metabolismo , Solo
10.
Appl Microbiol Biotechnol ; 107(10): 3341-3352, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37017732

RESUMO

The mountain pine beetle (MPB) has infested over 16 million hectares of pine forests in western Canada, killing over 50% of mature lodgepole pine, Pinus contorta, in British Columbia alone. There are few tools available to manage irruptive bark beetle populations and to mitigate tree mortality. Beauveria bassiana is an entomopathogenic fungus that causes mortality to several bark beetle species. However, the potential for B. bassiana as a biocontrol agent against pine beetle populations is unknown. We selected three strains of B. bassiana from several culture collections and evaluated their conidial stability under cold storage, in planta (greenhouse, and pine bolts) and in natura (forest stand, pine bolts, and live pines) conditions. The stability assays showed that all fungal strains maintained a minimum effective conidial yield through the assay durations (3-12 weeks). In addition, we adapted a biphasic liquid-solid fermentation approach for the large-scale production of conidial biomass, yielding up to a 100-fold increase in production. In greenhouse virulence assays, the mean lethal time of MPBs was reduced to 3-4 days upon treatment with B. bassiana, where high B. bassiana-associated mycosis was also observed. Furthermore, the application of B. bassiana formulation substantially affected the gallery network of MPBs in bolts in the field, resulting in shorter larval galleries and significantly reduced offspring production. Indeed, high titer treatments reduced the mean larvae per gallery to virtually zero. Together these results demonstrate that B. bassiana may be a viable biocontrol tool to reduce mountain pine beetle populations in pine forests in western Canada. KEY POINTS: • Three B. bassiana strains identified to be stable at various test conditions. • Large-scale conidial biomass production using liquid-solid biphasic fermentation. • Reproductive success of D. ponderosae significantly reduced by B. bassiana formulation.


Assuntos
Beauveria , Besouros , Pinus , Animais , Virulência , Pinus/microbiologia , Florestas , Larva , Esporos Fúngicos
11.
Appl Microbiol Biotechnol ; 107(7-8): 2027-2037, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36820899

RESUMO

The different organisms, ranging from plants to bacteria, and viruses that dwell on built cultural heritage can be passive or active participants in conservation processes. For the active participants, particular attention is generally given to organisms that play a positive role in bioprotection, bioprecipitation, bioconsolidation, bioremediation, biocleaning, and biological control and to those involved in providing ecosystem services, such as reducing temperature, pollution, and noise in urban areas. The organisms can also evolve or mutate in response to changes, becoming tolerant and resistant to biocidal treatments or acquiring certain capacities, such as water repellency or resistance to ultraviolet radiation. Our understanding of the capacities and roles of these active organisms is constantly evolving as bioprotection/biodeterioration, and biotreatment studies are conducted and new techniques for characterizing species are developed. This brief review article aims to shed light on interesting research that has been abandoned as well as on recent (some ongoing) studies opening up new scopes of research involving a wide variety of organisms and viruses, which are likely to receive more attention in the coming years. KEY POINTS: • Organisms and viruses can be active or passive players in heritage conservation • Biotreatment and ecosystem service studies involving organisms and viruses are shown • Green deal, health, ecosystem services, and global change may shape future research.


Assuntos
Ecossistema , Vírus , Humanos , Raios Ultravioleta , Plantas , Bactérias
12.
Plant Dis ; 107(9): 2701-2708, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36774574

RESUMO

Center rot of onion is caused by a complex of plant pathogenic Pantoea species, which can lead to significant yield losses in the field and during storage. Conventional growers use foliar protectants such as a mixture of copper bactericides and an ethylene-bis-dithiocarbamate (EBDC) fungicide to manage the disease; however, organic growers have limited management options besides copper-protectants. Biocontrol agents (BCAs) provide an alternative; however, their efficacy could be compromised due in part to their inability to colonize the foliage. We hypothesized that pretreatment with peroxide (OxiDate 2.0: a.i., hydrogen peroxide and peroxyacetic acid) enhances the colonizing ability of the subsequently applied BCAs, leading to effective center rot management. Field trials were conducted in 2020 and 2021 to assess the efficacy of peroxide, BCAs (Serenade ASO: Bacillus subtilis and BlightBan: Pseudomonas fluorescens), and an insecticide program (tank mix of spinosad and neem oil) to manage center rot. We observed no significant difference in foliar area under the disease progress curve (AUDPC) between the peroxide pretreated P. fluorescens plots and only P. fluorescens-treated plots in 2020 and 2021. Peroxide pretreatment before B. subtilis application significantly reduced the foliar AUDPC as compared with the stand-alone B. subtilis treatment in 2020; however, no such difference was observed in 2021. Similarly, peroxide pretreatment before either of the BCAs did not seem to reduce the incidence of bulb rot as compared with the stand-alone BCA treatment in any of the trials (2020 and 2021). Additionally, our foliar microbiome study showed comparatively higher P. fluorescens retention on peroxide pretreated onion foliage; however, at the end of the growing season, P. fluorescens was drastically reduced and was virtually nonexistent (<0.002% of the total reads). Overall, the pretreatment with peroxide had a limited effect in improving the foliar colonizing ability of BCAs and consequently a limited effect in managing center rot.


Assuntos
Fungicidas Industriais , Pantoea , Cobre , Doenças das Plantas/prevenção & controle , Peróxidos
13.
J Basic Microbiol ; 63(11): 1196-1218, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37208796

RESUMO

Worldwide mounting demand for better food production to nurture exasperating population emphasizes on reduced crop losses. The incidence of pathogens into the agricultural fields has tend to dwindle plethora of cereal, vegetable, and other fodder crops. This, in turn, has seriously impacted the economic losses on global scale. Apart from this, it is quite challenging to feed the posterity in the coming decades. To counteract this problem, various agrochemicals have been commercialized in the market that no doubt shows positive results but along with adversely affecting the ecosystem. Therefore, the excessive ill-fated use of agrochemicals to combat the plant pests and diseases highlights that alternatives to chemical pesticides are need of the hour. In recent days, management of plant diseases using plant-beneficial microbes is gaining interest as safer and potent alternatives to replace chemically based pesticides. Among these beneficial microbes, actinobacteria especially streptomycetes play considerable role in combating plant diseases along with promoting the plant growth and development along with their productivity and yield. The mechanisms exhibited by actinobacteria include antibiosis (antimicrobial compounds and hydrolytic enzymes), mycoparasitism, nutrient competition, and induction of resistance in plants. Thus, in cognizance with potential of actinobacteria as potent biocontrol agents, this review summarizes role of actinobacteria and the multifarious mechanisms exhibited by actinobacteria for commercial applications.


Assuntos
Actinobacteria , Praguicidas , Ecossistema , Produtos Agrícolas , Praguicidas/farmacologia , Agroquímicos
14.
Int J Mol Sci ; 24(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37569603

RESUMO

Biological plant protection presents a promising and exciting alternative to chemical methods for safeguarding plants against the increasing threats posed by plant diseases. This approach revolves around the utilization of biological control agents (BCAs) to suppress the activity of significant plant pathogens. Microbial BCAs have the potential to effectively manage crop disease development by interacting with pathogens or plant hosts, thereby increasing their resistance. However, the current efficacy of biological methods remains unsatisfactory, creating new research opportunities for sustainable plant cultivation management. In this context, microbial consortia, comprising multiple microorganisms with diverse mechanisms of action, hold promise in terms of augmenting the magnitude and stability of the overall antipathogen effect. Despite scientific efforts to identify or construct microbial consortia that can aid in safeguarding vital crops, only a limited number of microbial consortia-based biocontrol formulations are currently available. Therefore, this article aims to present a complex analysis of the microbial consortia-based biocontrol status and explore potential future directions for biological plant protection research with new technological advancements.


Assuntos
Produtos Agrícolas , Consórcios Microbianos , Doenças das Plantas/prevenção & controle , Agentes de Controle Biológico
15.
World J Microbiol Biotechnol ; 39(9): 237, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37391650

RESUMO

Phomopsis canker is one of the major devastating stem diseases that occur in tea plants caused by the fungal pathogen Phomopsis theae. Rapid development of this disease leads to a capital loss in the tea industry which demands an ecofriendly disease management strategy to control this aggressive pathogen. A total of 245 isolates were recovered from the tea rhizosphere and screened for in vitro plant growth promoting (PGP) traits and antagonism against P. theae. Among them, twelve isolates exhibited multifarious PGP traits including phytohormones, siderophore, hydrogen cyanide, salicylic acid production, phosphate solubilization, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and antifungal activity. In vitro studies on morphological, biochemical, and phylogenetic analyses classified the selected isolates as Pseudomonas fluorescens (VPF5), Bacillus subtilis (VBS3), Streptomyces griseus (VSG4) and Trichoderma viride (VTV7). Specifically, P. fluorescens VPF5 and B. subtilis VBS3 strains showed the highest level of PGP activities. On the other hand, VBS3 and VTV7 strains showed higher biocontrol efficacy in inhibiting mycelia growth and spore germination of P. theae. A detailed investigation on hydrolytic enzymes produced by antagonistic strains, which degrade the fungus cell wall, revealed that highest amount of chitinase and ß-1,3- glucanase in VTV7 and VBS3 strains. Further, the key antifungal secondary metabolites from these biocontrol agents associated with suppression of P. theae were identified using gas chromatography mass spectrometry. The above study clearly recognized the specific traits in the isolated microbes, which make them good candidates as plant growth-promoting rhizobacteria (PGPR) and biocontrol agents to improve plant growth and health. However, greenhouse trials and field application of these beneficial microbes is required to further confirm their efficacy for the management of stem canker in tea cultivation.


Assuntos
Antifúngicos , Camellia sinensis , Antifúngicos/farmacologia , Phomopsis , Filogenia , Chá
16.
Arch Microbiol ; 204(11): 666, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36214917

RESUMO

Chemical fertilizers and pesticides are an integral part of modern agriculture and are often associated with numerous environmental problems. Biological agents such as microorganisms can largely replace chemical fertilizers and pesticides. The proper use of selected microorganisms such as bacteria, fungi and viruses have several benefits for agriculture. These include a healthy soil microbiota, biological production of important compounds that promote plant health, and to be used as biocontrol agents (BCAs) that provide protection from plant pathogenic microorganisms. Scientists have found that several bacterial genera including Bacillus and Pseudomonas have antimicrobial activity against numerous pathogenic bacterial and fungal plant pathogens. Trichoderma, Aspergillus, and Penicillium are among the most common fungal genera used as BCAs against both bacterial and fungal plant pathogens. Several bacteriophages and mycoviruses are also found effective as BCAs against selective plant pathogens. Fusarium oxysporum is a commonly found microbial plant pathogen causing wilts and rots in plants. Overall, it can be concluded that the use of microbial BCAs is an effective practice against microbial plant pathogens.


Assuntos
Anti-Infecciosos , Praguicidas , Bactérias , Fatores Biológicos , Fertilizantes , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Plantas/microbiologia , Solo
17.
BMC Nephrol ; 23(1): 279, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945494

RESUMO

BACKGROUND: The first case of Taralomyces flavus infection in human and peritoneal dialysis (PD) patient after exposure to biocontrol agent fumes is reported here. CASE PRESENTATION: A 77-year-old Thai female farmer with kidney failure presented with peritonitis and PD catheter obstruction from fungal biofilms. The potential root cause of infection was associated with exposure to biocontrol-agent fumes containing pathogen during agricultural work in her garden. This source of infection has not been mentioned previously. Showering and changing clothes right after outdoor activity with a high density of fungal matters or dust should be added to the routine aseptic technique before performing PD bag exchange to prevent the system contamination. Although the patient received early treatment with liposomal amphotericin B, itraconazole, and catheter removal, according to the ISPD Guideline 2016 and the Global Guideline 2021, the outcome was unfavorable. Antifungal susceptibility testing later revealed that the pathogen was only susceptible to voriconazole. Thus, antifungal susceptibility should be tested if the patient fails or slowly responds to the primary antifungal regimen. CONCLUSIONS: T. flavus peritonitis is reported here after exposure to biocontrol-agent fumes containing the pathogen. This work also alerts and reiterates nephrology peers to be aware of this overlooked source of peritonitis, the exposure to dusty environments, specifically containing biocontrol-agent fumes.


Assuntos
Diálise Peritoneal , Peritonite , Talaromyces , Idoso , Antifúngicos/efeitos adversos , Feminino , Humanos , Diálise Peritoneal/efeitos adversos , Peritonite/etiologia , Peritonite/microbiologia
18.
Bull Entomol Res ; 112(6): 715-723, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36200451

RESUMO

Tools that could be used to subvert the insect diapause response offer potential for insect pest management as well as for the experimental manipulation of insects and the facilitation of mass rearing procedures. In some cases, it is desirable to break diapause on demand and in other cases, it may be attractive to exploit diapause for long-term storage of biocontrol agents or valuable experimental lines. This review highlights some of the diapause disruptors reported in the literature, as well as chemical and physical manipulations that can be used to extend diapause or even induce diapause in an insect not programmed for diapause. The insect hormones are quite effective agents for breaking diapause and in some cases for extending the duration of diapause, but a collection of other chemical agents can also act as potent diapause disruptors, e.g. organic solvents, weak acids and bases, carbon dioxide, imidazole compounds, LSD, deuterium oxide, DMSO, ouabain, cholera toxin, cyclic GMP, heavy metals, and hydrogen peroxide. Physical manipulations such as artificial light at night, anoxia, shaking and heat shock are also known diapause disruptors. Some of these documented manipulations prevent diapause, others terminate diapause immediately, others alter the duration of diapause, and a few compounds can induce a diapause-like state in insects that are not programmed for diapause. The diversity of tools noted in the literature offers promise for the development of new tools or manipulations that possibly could be used to disrupt diapause or manage diapause in controlled laboratory experiments and in mass-rearing facilities.


Assuntos
Diapausa de Inseto , Diapausa , Hormônios de Inseto , Animais , Hormônios de Inseto/fisiologia , Insetos/fisiologia , Resposta ao Choque Térmico
19.
Rev Sci Tech ; 41(1): 228-250, 2022 May.
Artigo em Inglês, Francês, Espanhol | MEDLINE | ID: mdl-35925618

RESUMO

While the information on live insect shipments provided in this thematic issue of the Scientific and Technical Review could not be exhaustive, it clearly represents a broad variety of trade, of substantial value, involving many stakeholders throughout the world. The contributions to this issue demonstrate that most of the trade in insects is carried out safely and efficiently. The concerns related to shipping insects described within this issue fall broadly into four categories: risks to human, animal and environmental health; delays and loss of quality; refusal of carriage; and high and variable costs. Some opportunities for improvements to insect shipping for diverse stakeholders are shown across these four areas of concern, with specific recommendations and a general call for further collaboration among stakeholders.


À défaut d'être exhaustives, les informations fournies dans ce numéro thématique de la Revue scientifique et technique consacré aux expéditions d'insectes vivants recouvrent clairement un très large éventail de ces échanges, qui représentent une valeur importante et auxquels participent de nombreux intervenants dans le monde entier. Les contributions réunies dans ce numéro montrent que l'essentiel des échanges d'insectes se déroule sans risques associés et de manière efficiente. Les sujets de préoccupation relatifs aux expéditions d'insectes mis en avant dans ce numéro relèvent, en général, de l'une des quatre catégories suivantes : risques pour la santé humaine, animale et environnementale ; retards et perte de qualité ; refus de transport ; coüts élevés et sujets à variations. Les auteurs font état des perspectives d'amélioration des expéditions d'insectes qui s'offrent à plusieurs parties prenantes, pour chacune de ces catégories, et présentent des recommandations spécifiques ainsi qu'un appel général à renforcer la collaboration pluri-acteurs.


Aunque la información presentada en este número temático de la Revista científica y técnica sobre el transporte de insectos vivos no puede ser exhaustiva, sí da clara cuenta de diversos tipos de comercio que revisten importancia y convocan a numerosos interlocutores del mundo entero. Los artículos de este número evidencian que el comercio de insectos discurre la mayor parte del tiempo con eficacia y en condiciones seguras. Los problemas ligados al transporte de insectos que se exponen en este número corresponden, en líneas generales, a cuatro clases: riesgos para la salud humana, animal o ambiental; retrasos y pérdida de calidad; denegación de transporte; y costos elevados y variables. En relación con estos cuatro ámbitos problemáticos, aquí se apuntan algunas posibilidades para que distintas partes introduzcan mejoras en el transporte de insectos, se presentan recomendaciones específicas y se hace una exhortación general a una mayor colaboración entre los interlocutores del sector.


Assuntos
Insetos , Animais , Humanos
20.
Int J Mol Sci ; 23(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955951

RESUMO

The cultivation of soilless tomato in greenhouses has increased considerably, but little is known about the assembly of the root microbiome compared to plants grown in soil. To obtain such information, we constructed an assay in which we traced the bacterial and fungal communities by amplicon-based metagenomics during the cultivation chain from nursery to greenhouse. In the greenhouse, the plants were transplanted either into agricultural soil or into coconut fiber bags (soilless). At the phylum level, bacterial and fungal communities were primarily constituted in all microhabitats by Proteobacteria and Ascomycota, respectively. The results showed that the tomato rhizosphere microbiome was shaped by the substrate or soil in which the plants were grown. The microbiome was different particularly in terms of the bacterial communities. In agriculture, enrichment has been observed in putative biological control bacteria of the genera Pseudomonas and Bacillus and in potential phytopathogenic fungi. Overall, the study describes the different shaping of microbial communities in the two cultivation methods.


Assuntos
Ascomicetos , Microbiota , Solanum lycopersicum , Bactérias/genética , Solanum lycopersicum/microbiologia , Raízes de Plantas/microbiologia , Rizosfera , Solo , Microbiologia do Solo
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