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1.
Int J Mol Sci ; 23(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35163522

RESUMO

Plant diseases that are caused by fungi and nematodes have become increasingly serious in recent years. However, there are few pesticide chemicals that can be used for the joint control of fungi and nematodes on the market. To solve this problem, a series of novel 1,2,4-oxadiazole derivatives containing amide fragments were designed and synthesized. Additionally, the bioassays revealed that the compound F15 demonstrated excellent antifungal activity against Sclerotinia sclerotiorum (S. sclerotiorum) in vitro, and the EC50 value of that was 2.9 µg/mL, which is comparable with commonly used fungicides thifluzamide and fluopyram. Meanwhile, F15 demonstrated excellent curative and protective activity against S. sclerotiorum-infected cole in vivo. The scanning electron microscopy results showed that the hyphae of S. sclerotiorum treated with F15 became abnormally collapsed and shriveled, thereby inhibiting the growth of the hyphae. Furthermore, F15 exhibited favorable inhibition against the succinate dehydrogenase (SDH) of the S. sclerotiorum (IC50 = 12.5 µg/mL), and the combination mode and binding ability between compound F15 and SDH were confirmed by molecular docking. In addition, compound F11 showed excellent nematicidal activity against Meloidogyne incognita at 200 µg/mL, the corrected mortality rate was 93.2%, which is higher than that of tioxazafen.


Assuntos
Antifúngicos/síntese química , Ascomicetos/crescimento & desenvolvimento , Oxidiazóis/síntese química , Succinato Desidrogenase/metabolismo , Amidas/química , Antifúngicos/química , Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Linhagem Celular , Desenho de Fármacos , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Humanos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Oxidiazóis/química , Oxidiazóis/farmacologia , Plantas/efeitos dos fármacos , Plantas/microbiologia , Plantas/parasitologia , Conformação Proteica , Relação Estrutura-Atividade , Succinato Desidrogenase/química
2.
PLoS One ; 17(2): e0263462, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35143545

RESUMO

Detoxification enzymes play significant roles in the interactions between insects and host plants, wherein detoxification-related genes make great contributions. As herbivorous pests, aphids reproduce rapidly due to parthenogenesis. They are good biological materials for studying the mechanisms that allow insect adaptation to host plants. Insect detoxification gene families are associated with insect adaptation to host plants. The Aphidinae is the largest subfamily in the Aphididae with at least 2483 species in 256 genera in 2 tribes: the Macrosiphini (with 3/4 of the species) and the Aphidini. Most aphid pests on crops and ornamental plants are Aphidinae. Members of the Aphidinae occur in nearly every region of the world. The body shape and colour vary significantly. To research the role that detoxification gene families played in the process of aphid adaptation to host evolution, we analyzed the phylogeny and evolution of these detoxification gene families in Aphidinae. In general, the P450/GST/CCE gene families contract, whereas the ABC/UGT families are conserved in Aphidinae species compared to these families in other herbivorous insects. Genus-specific expansions of P450 CYP4, and GST Delta have occurred in the genus Acyrthosiphon. In addition, the evolutionary rates of five detoxification gene families in the evolution process of Aphidinae are different. The comparison of five detoxification gene families among nine Aphidinae species and the estimated relative evolutionary rates provided herein support an understanding of the interaction between and the co-evolution of Aphidinae and plants.


Assuntos
Afídeos/genética , Coevolução Biológica , Genes de Insetos , Plantas/parasitologia , Adaptação Fisiológica , Animais , Afídeos/fisiologia , Filogenia , Plantas/genética
3.
J Biol Chem ; 298(4): 101734, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35181340

RESUMO

Crop parasites of the Striga genera are a major biological deterrent to food security in Africa and are one of the largest obstacles to poverty alleviation on the continent. Striga seeds germinate by sensing small-molecule hormones, strigolactones (SLs), that emanate from host roots. Although SL receptors (Striga hermonthica HYPOSENSITIVE TO LIGHT [ShHTL]) have been identified, discerning their function has been difficult because these parasites cannot be easily grown under laboratory conditions. Moreover, many Striga species are obligate outcrossers that are not transformable, hence not amenable to genetic analysis. By combining phenotypic screening with ShHTL structural information and hybrid drug discovery methods, we discovered a potent SL perception inhibitor for Striga, dormirazine (DOZ). Structural analysis of this piperazine-based antagonist reveals a novel binding mechanism, distinct from that of known SLs, blocking access of the hormone to its receptor. Furthermore, DOZ reduces the flexibility of protein-protein interaction domains important for receptor signaling to downstream partners. In planta, we show, via temporal additions of DOZ, that SL receptors are required at a specific time during seed conditioning. This conditioning is essential to prime seed germination at the right time; thus, this SL-sensitive stage appears to be critical for adequate receptor signaling. Aside from uncovering a function for ShHTL during seed conditioning, these results suggest that future Ag-Biotech Solutions to Striga infestations will need to carefully time the application of antagonists to exploit receptor availability and outcompete natural SLs, critical elements for successful parasitic plant invasions.


Assuntos
Lactonas , Extratos Vegetais , Plantas , Striga , Germinação/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Lactonas/farmacologia , Doenças das Plantas/prevenção & controle , Extratos Vegetais/farmacologia , Plantas/parasitologia , Striga/efeitos dos fármacos , Striga/metabolismo
4.
Sci Rep ; 12(1): 1116, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064176

RESUMO

Fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), is a highly polyphagous invasive plant pest that has expanded its global geographic distribution, including recently into much of Australia. Rapid diagnostic tests are required for identification of FAW to assist subsequent management and control. We developed a new loop-mediated isothermal amplification (LAMP) assay based on the mitochondrial cytochrome c oxidase subunit I (COI) gene for accurate and timely diagnosis of FAW in the field. The specificity of the new assay was tested against a broad panel of twenty non-target noctuids, including eight other Spodoptera species. Only S. frugiperda samples produced amplification within 20 min, with an anneal derivative temperature of 78.3 ± 0.3 °C. A gBlock dsDNA fragment was developed and trialled as a synthetic positive control, with a different anneal derivative of 81 °C. The new FAW LAMP assay was able to detect FAW DNA down to 2.4 pg, similar to an existing laboratory-based real-time PCR assay. We also trialled the new FAW assay with a colorimetric master mix and found it could successfully amplify positive FAW samples in half the time compared to an existing FAW colorimetric LAMP assay. Given the high sensitivity and rapid amplification time, we recommend the use of this newly developed FAW LAMP assay in a portable real-time fluorometer for in-field diagnosis of FAW.


Assuntos
Espécies Introduzidas , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Plantas/parasitologia , Spodoptera/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Larva , Spodoptera/enzimologia
5.
Nucleic Acids Res ; 50(D1): D837-D847, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34788826

RESUMO

Since 2005, the Pathogen-Host Interactions Database (PHI-base) has manually curated experimentally verified pathogenicity, virulence and effector genes from fungal, bacterial and protist pathogens, which infect animal, plant, fish, insect and/or fungal hosts. PHI-base (www.phi-base.org) is devoted to the identification and presentation of phenotype information on pathogenicity and effector genes and their host interactions. Specific gene alterations that did not alter the in host interaction phenotype are also presented. PHI-base is invaluable for comparative analyses and for the discovery of candidate targets in medically and agronomically important species for intervention. Version 4.12 (September 2021) contains 4387 references, and provides information on 8411 genes from 279 pathogens, tested on 228 hosts in 18, 190 interactions. This provides a 24% increase in gene content since Version 4.8 (September 2019). Bacterial and fungal pathogens represent the majority of the interaction data, with a 54:46 split of entries, whilst protists, protozoa, nematodes and insects represent 3.6% of entries. Host species consist of approximately 54% plants and 46% others of medical, veterinary and/or environmental importance. PHI-base data is disseminated to UniProtKB, FungiDB and Ensembl Genomes. PHI-base will migrate to a new gene-centric version (version 5.0) in early 2022. This major development is briefly described.


Assuntos
Bases de Dados Factuais , Interações Hospedeiro-Patógeno/genética , Fenótipo , Interface Usuário-Computador , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/patogenicidade , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Diplomonadida/classificação , Diplomonadida/genética , Diplomonadida/patogenicidade , Fungos/classificação , Fungos/genética , Fungos/patogenicidade , Insetos/classificação , Insetos/genética , Insetos/patogenicidade , Internet , Nematoides/classificação , Nematoides/genética , Nematoides/patogenicidade , Filogenia , Plantas/microbiologia , Plantas/parasitologia , Virulência
6.
Phytopathology ; 112(4): 881-887, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34495679

RESUMO

Ditylenchus gallaeformans is a plant parasitic nematode that induces galls on aboveground parts of Melastomataceae plants. It differs from most gall-inducing nematodes in that it is not an endoparasite and has been considered as a possible biological control agent against invasive species of Miconia. Little is known about D. gallaeformans biology, genetic differences among populations, and host preferences. This study examined the genetic differences among D. gallaeformans populations from different locations and host species and the phylogenetic relationships among them. Nematodes were collected from galls in plants from Costa Rica, Dominica, and Trinidad. The Cytochrome c oxidase 1 (cox1) region was sequenced from a total of 33 individual nematodes isolated from 33 different plant individuals, representing 21 species of Melastomataceae. Phylogenetic reconstructions, haplotype networks, and analysis of molecular variance showed that the species is monophyletic and has three major clades, which were mostly consistent with geographic location but not with host species. The first clade was composed by two subclades, one with individuals from Costa Rica and one with individuals from Dominica. The second and third clades comprised nematodes only from Trinidad. Overall, there is no evidence of host-species specialization in D. gallaeformans. Biocontrol efforts using the nematode against invasive Miconia could focus on geographical location matching but likely will not need to match host species.


Assuntos
Melastomataceae , Nematoides , Tylenchida , Animais , Genética Populacional , Melastomataceae/parasitologia , Nematoides/genética , Filogenia , Doenças das Plantas , Folhas de Planta/parasitologia , Plantas/parasitologia
7.
Microbiol Res ; 254: 126888, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34700185

RESUMO

Phyllosphere or aerial surface of plants represents the globally largest and peculiar microbial habitat that inhabits diverse and rich communities of bacteria, fungi, viruses, cyanobacteria, actinobacteria, nematodes, and protozoans. These hyperdiverse microbial communities are related to the host's specific functional traits and influence the host's physiology and the ecosystem's functioning. In the last few years, significant advances have been made in unravelling several aspects of phyllosphere microbiology, including diversity and microbial community composition, dynamics, and functional interactions. This review highlights the current knowledge about the assembly, structure, and composition of phyllosphere microbial communities across spatio-temporal scales, besides functional significance of different microbial communities to the plant host and the surrounding environment. The knowledge will help develop strategies for modelling and manipulating these highly beneficial microbial consortia for furthering scientific inquiry into their interactions with the host plants and also for their useful and economic utilization.


Assuntos
Biodiversidade , Interações entre Hospedeiro e Microrganismos , Microbiota , Plantas , Microbiota/fisiologia , Plantas/microbiologia , Plantas/parasitologia , Plantas/virologia
8.
Sci Rep ; 11(1): 21635, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737375

RESUMO

Plant taxonomic and functional diversity promotes interactions at higher trophic levels, but the contribution of functional diversity effects to multitrophic interactions and ecosystem functioning remains unclear. We investigated this relationship in a factorial field experiment comparing the effect of contrasting plant communities on parasitism rates in five herbivore species. We used a mechanistic trait-matching approach between plant and parasitoids to determine the amount of nectar available and accessible to parasitoids. This trait-matching approach best explained the rates of parasitism of each herbivorous species, confirming the predominant role of mass-ratio effects. We found evidence for an effect of functional diversity only in analyses considering the ability of plant communities to support the parasitism of all herbivores simultaneously. Multi-species parasitism was maximal at intermediate levels of functional diversity. Plant specific richness had a negligible influence relative to functional metrics. Plant communities providing large amounts of accessible nectar and with intermediate levels of functional diversity were found to be the most likely to enhance the conservation biological control of diverse crop herbivores.


Assuntos
Parasitos/fisiologia , Plantas/metabolismo , Plantas/parasitologia , Animais , Biodiversidade , Fenômenos Biológicos , Classificação/métodos , Ecologia/métodos , Ecossistema , Herbivoria/fisiologia , Parasitos/metabolismo , Parasitos/patogenicidade
9.
Sci Rep ; 11(1): 19473, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593852

RESUMO

Herbivorous insects can escape the strong pressure of parasitoids by switching to feeding on new host plants. Parasitoids can adapt to this change but at the cost of changing their preferences and performance. For gregarious parasitoids, fitness changes are not always observable in the F1 generation but only in the F2 generation. Here, with the model species and gregarious parasitoid Anaphes flavipes, we examined fitness changes in the F1 generation under pressure from the simulation of host switching, and by a new two-generation approach, we determined the impact of these changes on fitness in the F2 generation. We showed that the parasitoid preference for host plants depends on hatched or oviposited learning in relation to the possibility of parasitoid decisions between different host plants. Interestingly, we showed that after simulation of parasitoids following host switching, in the new environment of a fictitious host plant, parasitoids reduced the fictitious host. At the same time, parasitoids also reduced fertility because in fictitious hosts, they are not able to complete larval development. However, from a two-generation approach, the distribution of parasitoid offspring into both native and fictitious hosts caused lower parasitoid clutch size in native hosts and higher individual offspring fertility in the F2 generation.


Assuntos
Aptidão Genética , Interações Hospedeiro-Parasita , Insetos , Animais , Herbivoria , Plantas/parasitologia
10.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34681926

RESUMO

Spodoptera frugiperda is a highly polyphagous and invasive agricultural pest that can harm more than 300 plants and cause huge economic losses to crops. Symbiotic bacteria play an important role in the host biology and ecology of herbivores, and have a wide range of effects on host growth and adaptation. In this study, high-throughput sequencing technology was used to investigate the effects of different hosts (corn, wild oat, oilseed rape, pepper, and artificial diet) on gut microbial community structure and diversity. Corn is one of the most favored plants of S. frugiperda. We compared the gut microbiota on corn with and without a seed coating agent. The results showed that Firmicutes and Bacteroidetes dominated the gut microbial community. The microbial abundance on oilseed rape was the highest, the microbial diversity on wild oat was the lowest, and the microbial diversity on corn without a seed coating agent was significantly higher than that with such an agent. PCoA analysis showed that there were significant differences in the gut microbial community among different hosts. PICRUSt analysis showed that most of the functional prediction categories were related to metabolic and cellular processes. The results showed that the gut microbial community of S. frugiperda was affected not only by the host species, but also by different host treatments, which played an important role in host adaptation. It is important to deepen our understanding of the symbiotic relationships between invasive organisms and microorganisms. The study of the adaptability of host insects contributes to the development of more effective and environmentally friendly pest management strategies.


Assuntos
Bactérias/classificação , Plantas/parasitologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Spodoptera/fisiologia , Animais , Avena/parasitologia , Bactérias/genética , Bactérias/isolamento & purificação , Brassica napus/parasitologia , Capsicum/parasitologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Microbioma Gastrointestinal , Sequenciamento de Nucleotídeos em Larga Escala , Especificidade de Hospedeiro , Filogenia , Plantas/classificação , Spodoptera/microbiologia , Zea mays/parasitologia
11.
Opt Express ; 29(18): 28461-28480, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34614977

RESUMO

Studying in vivo feeding and other behaviors of small insects, such as aphids, is important for understanding their lifecycle and interaction with the environment. In this regard, the EPG (electrical penetration graph) technique is widely used to study the feeding activity in aphids. However, it is restricted to recording feeding of single insects and requires wiring insects to an electrode, impeding free movement. Hence, easy and straightforward collective observations, e.g. of groups of aphids on a plant, or probing other aphid activities in various body parts, is not possible. To circumvent these drawbacks, we developed a method based on an optical technique called laser speckle contrast imaging (LSCI). It has the potential for direct, non-invasive and contactless monitoring of a broad range of internal and external activities such as feeding, hemolymph cycling and muscle contractions in aphids or other insects. The method uses a camera and coherent light illumination of the sample. The camera records the laser speckle dynamics due to the scattering and interference of light caused by moving scatters in a probed region of the insect. Analyzing the speckle contrast allowed us to monitor and extract the activity information during aphid feeding on leaves or on artificial medium containing tracer particles. We present evidence that the observed speckle dynamics might be caused by muscle contractions, movement of hemocytes in the circulatory system or food flows in the stylets. This is the first time such a remote sensing method has been applied for optical mapping of the biomechanical activities in aphids.


Assuntos
Afídeos/fisiologia , Imagem de Contraste de Manchas a Laser/métodos , Animais , Fenômenos Biomecânicos , Desenho de Equipamento , Comportamento Alimentar , Hemolinfa/fisiologia , Contração Muscular/fisiologia , Plantas/parasitologia , Tecnologia de Sensoriamento Remoto , Salivação
12.
World J Microbiol Biotechnol ; 37(10): 180, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34562178

RESUMO

Agricultural production is one of most important activities for food supply and demand, that provides a source of raw materials, and generates commercial opportunities for other industries around the world. It may be both positively and negatively affected by climatic and biological factors. Negative biological factors are those caused by viruses, bacteria, or parasites. Given the serious problems posed by phytoparasitic nematodes for farmers, causing crop losses globally every year, the agrochemical industry has developed compounds with the capacity to inhibit their development; however, they can cause the death of other beneficial organisms and their lixiviation can contaminate the water table. On the other hand, the positive biological factors are found in biotechnology, the scientific discipline that develops products, such as nematophagous fungi (of which Purpureocillium lilacinum and Pochonia chlamydosporia have the greatest potential), for the control of pests and/or diseases. The present review focuses on the importance of nematophagous fungi, particularly sedentary endoparasitic nematodes, their research on the development of biological control agents, the mass production of fungi Purpureocillium lilacinum and Pochonia chlamydosporia, and their limited commercialization due to the lack of rigorous methods that enable the anticipation of complex interactions between plant and phytopathogenic agents.


Assuntos
Agentes de Controle Biológico , Fungos , Nematoides/microbiologia , Patologia Vegetal , Animais , Fungos/crescimento & desenvolvimento , Fungos/patogenicidade , Hypocreales/crescimento & desenvolvimento , Hypocreales/patogenicidade , Controle Biológico de Vetores , Plantas/parasitologia
13.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502330

RESUMO

Galls are characteristic plant structures formed by cell size enlargement and/or cell proliferation induced by parasitic or pathogenic organisms. Insects are a major inducer of galls, and insect galls can occur on plant leaves, stems, floral buds, flowers, fruits, or roots. Many of these exhibit unique shapes, providing shelter and nutrients to insects. To form unique gall structures, gall-inducing insects are believed to secrete certain effector molecules and hijack host developmental programs. However, the molecular mechanisms of insect gall induction and development remain largely unknown due to the difficulties associated with the study of non-model plants in the wild. Recent advances in next-generation sequencing have allowed us to determine the biological processes in non-model organisms, including gall-inducing insects and their host plants. In this review, we first summarize the adaptive significance of galls for insects and plants. Thereafter, we summarize recent progress regarding the molecular aspects of insect gall formation.


Assuntos
Interações Hospedeiro-Parasita , Insetos/fisiologia , Tumores de Planta/etiologia , Plantas/parasitologia , Animais
14.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361721

RESUMO

To improve the proinsecticidal activity and phloem mobility of amino acid-tralopyril conjugates further, nine conjugates were designed and synthesized by introducing glutamic acid to tralopyril, and the length of the linker between glutamic acid and tralopyril ranged from 2 atoms to 10 atoms. The results of insecticidal activity against the third-instar larvae of P. xylostella showed that conjugates 42, 43, 44,and 45 (straight-chain containing 2-5 atoms) exhibited good insecticidal activity, and their LC50 values were 0.2397 ± 0.0366, 0.4413 ± 0.0647, 0.4400 ± 0.0624, and 0.4602 ± 0.0655 mM, respectively. The concentrations of conjugates 43-45 were higher than that of conjugate 42 in the phloem sap at 2 h, and conjugate 43 showed the highest concentration. The introduction of glutamic acid can improve phloem mobility. The in vivo metabolism of conjugates 42 and 43 was investigated in P. xylostella, and the parent compound tralopyril was detected at concentrations of 0.5950 and 0.3172 nmol/kg, respectively. According to the above results, conjugates 42 and 43 were potential phloem mobile pro-insecticide candidates.


Assuntos
Ácido Glutâmico/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Pró-Fármacos/farmacologia , Pirróis/farmacologia , Animais , Transporte Biológico , Biotransformação , Concentração Inibidora 50 , Inseticidas/síntese química , Inseticidas/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Longevidade/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Floema/metabolismo , Floema/parasitologia , Plantas/metabolismo , Plantas/parasitologia , Pró-Fármacos/síntese química , Pró-Fármacos/metabolismo , Piretrinas/metabolismo , Piretrinas/farmacologia , Pirróis/síntese química , Pirróis/metabolismo , Relação Estrutura-Atividade
15.
Commun Biol ; 4(1): 847, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234279

RESUMO

The aphid Myzus persicae is a destructive agricultural pest that displays an exceptional ability to develop resistance to both natural and synthetic insecticides. To investigate the evolution of resistance in this species we generated a chromosome-scale genome assembly and living panel of >110 fully sequenced globally sampled clonal lines. Our analyses reveal a remarkable diversity of resistance mutations segregating in global populations of M. persicae. We show that the emergence and spread of these mechanisms is influenced by host-plant associations, uncovering the widespread co-option of a host-plant adaptation that also offers resistance against synthetic insecticides. We identify both the repeated evolution of independent resistance mutations at the same locus, and multiple instances of the evolution of novel resistance mechanisms against key insecticides. Our findings provide fundamental insights into the genomic responses of global insect populations to strong selective forces, and hold practical relevance for the control of pests and parasites.


Assuntos
Afídeos/genética , Evolução Molecular , Variação Genética , Genoma de Inseto/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Animais , Afídeos/classificação , Afídeos/fisiologia , Sequência de Bases , Genômica/métodos , Geografia , Interações Hospedeiro-Parasita/efeitos dos fármacos , Mutação , Filogenia , Plantas/parasitologia , Polimorfismo de Nucleotídeo Único , Homologia de Sequência do Ácido Nucleico
16.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202141

RESUMO

Intestinal symbiotic bacteria have played an important role in the digestion, immunity detoxification, mating, and reproduction of insects during long-term coevolution. The oriental fruit moth, Grapholita molesta, is an important fruit tree pest worldwide. However, the composition of the G. molesta microbial community, especially of the gut microbiome, remains unclear. To explore the differences of gut microbiota of G. molesta when reared on different host plants, we determined the gut bacterial structure when G. molesta was transferred from an artificial diet to different host plants (apples, peaches, nectarines, crisp pears, plums, peach shoots) by amplicon sequencing technology. The results showed that Proteobacteria and Firmicutes are dominant in the gut microbiota of G. molesta. Plum-feeding G. molesta had the highest richness and diversity of gut microbiota, while apple-feeding G. molesta had the lowest. PCoA and PERMANOVA analysis revealed that there were significant differences in the gut microbiota structure of G. molesta on different diets. PICRUSt2 analysis indicated that most of the functional prediction pathways were concentrated in metabolic and cellular processes. Our results confirmed that gut bacterial communities of G. molesta can be influenced by host diets and may play an important role in host adaptation.


Assuntos
Microbioma Gastrointestinal , Lepidópteros/microbiologia , Análise de Variância , Animais , Biologia Computacional/métodos , Interações Hospedeiro-Parasita , Metagenômica/métodos , Plantas/parasitologia , RNA Ribossômico 16S/genética
17.
Nat Microbiol ; 6(8): 1000-1006, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34211160

RESUMO

Phytophthora species, classified as oomycetes, are among the most destructive plant pathogens worldwide and pose a substantial threat to food security. Plant pathogens have developed various methods to breach the cuticle and walls of plant cells. For example, plant-pathogenic fungi use a 'brute-force' approach by producing a specialized and fortified invasion organ to generate invasive pressures. Unlike in fungi, the biomechanics of host invasion in oomycetes remains poorly understood. Here, using a combination of surface-deformation imaging, molecular-fracture sensors and modelling, we find that Phytophthora infestans, Phytophthora palmivora and Phytophthora capsici slice through the plant surface to gain entry into host tissues. To distinguish this mode of entry from the brute-force approach of fungi that use appressoria, we name this oomycete entry without appressorium formation 'naifu' invasion. Naifu invasion relies on polarized, non-concentric, force generation onto the surface at an oblique angle, which concentrates stresses at the site of invasion to enable surface breaching. Measurements of surface deformations during invasion of artificial substrates reveal a polarized mechanical geometry that we describe using a mathematical model. We confirm that the same mode of entry is used on real hosts. Naifu invasion uses actin-mediated polarity, surface adherence and turgor generation to enable Phytophthora to invade hosts without requiring specialized organs or vast turgor generation.


Assuntos
Phytophthora infestans/fisiologia , Doenças das Plantas/parasitologia , Interações Hospedeiro-Patógeno , Plantas/parasitologia
18.
Math Biosci ; 340: 108670, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34302819

RESUMO

The spotted lanternfly (SLF) is an invasive pest that emerged in the US less than a decade ago. With few natural enemies and an ability to feed on a wide variety of readily available plants the population has grown rapidly. It is causing damage to a wide range of natural and economically important farmed plants and at present there is no known way to stop the growth and spread of the population. However, a number of control measures have been proposed to limit the growth and the effectiveness of some of these have been assessed via empirical studies. Studies to estimate the natural mortality rate of the lanternfly's different life stages and other properties of its life cycle are also available. However, no attempt to integrate this empirical information to estimate population level characteristics such as the population growth rate and the potential effects of proposed control measures can be found in the literature. Here, we introduce a simple population dynamics model parameterized using available information in the literature to obtain estimates of this type. Our model suggests that the annual growth rate of the SLF population in the US is 5.47, that only three out of six proposed control measures considered here have the potential to decrease the population even if we can find and treat each SLF in every stage, and that even with a combined strategy involving the most effective proposed control measures about 35% of all SLF in the relevant stages must be found and treated to turn the current population growth into decline. Suggesting that eradication of the spotted lanternfly over larger geographical areas in the US will be challenging, and we believe that the modeling framework presented here may be useful in providing estimates to inform feasibility assessment of proposed management efforts.


Assuntos
Hemípteros , Espécies Introduzidas , Estágios do Ciclo de Vida , Modelos Biológicos , Controle de Pragas , Animais , Hemípteros/fisiologia , Espécies Introduzidas/estatística & dados numéricos , Controle de Pragas/métodos , Plantas/parasitologia , Dinâmica Populacional , Crescimento Demográfico
19.
Trends Parasitol ; 37(11): 947-958, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34162521

RESUMO

Plant-parasitic nematodes (PPNs) remain a hardly treatable problem in many crops worldwide. Low efficacy of many biocontrol agents may be due to negligence of the native microbiota that is naturally associated with nematodes in soil, and which may protect nematodes against microbial antagonists. This phenomenon is more extensively studied for other nematode parasites, so we compiled these studies and drew parallels to the existing knowledge on PPN. We describe how microbial-mediated modulation of host immune responses facilitate nematode parasitism and discuss the role of Caenorhabditis elegans-protective microbiota to get an insight into the microbial protection of PPNs in soil. Molecular mechanisms of PPN-microbial interactions are also discussed. An understanding of microbial-aided PPN performance is thus pivotal for efficient management of PPNs.


Assuntos
Nematoides , Parasitos , Animais , Caenorhabditis elegans , Nematoides/fisiologia , Plantas/parasitologia , Solo
20.
Nat Commun ; 12(1): 3911, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162855

RESUMO

Empirical measurements of ecological networks such as food webs and mutualistic networks are often rich in structure but also noisy and error-prone, particularly for rare species for which observations are sparse. Focusing on the case of plant-pollinator networks, we here describe a Bayesian statistical technique that allows us to make accurate estimates of network structure and ecological metrics from such noisy observational data. Our method yields not only estimates of these quantities, but also estimates of their statistical errors, paving the way for principled statistical analyses of ecological variables and outcomes. We demonstrate the use of the method with an application to previously published data on plant-pollinator networks in the Seychelles archipelago and Kosciusko National Park, calculating estimates of network structure, network nestedness, and other characteristics.


Assuntos
Algoritmos , Insetos/fisiologia , Modelos Biológicos , Plantas/parasitologia , Polinização/fisiologia , Animais , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Interações Hospedeiro-Parasita , New South Wales , Parques Recreativos , Seicheles
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