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1.
BMC Plant Biol ; 21(1): 358, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348650

RESUMO

BACKGROUND: The South America pinworm, Tuta absoluta, is a destructive pest of tomato that causes important losses worldwide. Breeding of resistant/tolerant tomato cultivars could be an effective strategy for T. absoluta management but, despite the economic importance of tomato, very limited information is available about its response to this treat. To elucidate the defense mechanisms to herbivore feeding a comparative analysis was performed between a tolerant and susceptible cultivated tomato at both morphological and transcriptome level to highlight constitutive leaf barriers, molecular and biochemical mechanisms to counter the effect of T. absoluta attack. RESULTS: The tolerant genotype showed an enhanced constitutive barrier possibly as result of the higher density of trichomes and increased inducible reactions upon mild infestation thanks to the activation/repression of key transcription factors regulating genes involved in cuticle formation and cell wall strength as well as of antinutritive enzymes, and genes involved in the production of chemical toxins and bioactive secondary metabolites. CONCLUSIONS: Overall, our findings suggest that tomato resilience to the South America pinworm is achieved by a combined strategy between constitutive and induced defense system. A well-orchestrated modulation of plant transcription regulation could ensure a trade-off between defense needs and fitness costs. Our finding can be further exploited for developing T. absoluta tolerant cultivars, acting as important component of integrated pest management strategy for more sustainable production.


Assuntos
Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Doenças das Plantas/genética , Folhas de Planta/genética , Transcriptoma , Animais , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Interações Hospedeiro-Parasita , Larva/fisiologia , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Mariposas/fisiologia , Doenças das Plantas/parasitologia , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA-Seq/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tricomas/genética , Tricomas/metabolismo , Tricomas/parasitologia
2.
Science ; 373(6556): 774-779, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385392

RESUMO

The oomycete Phytophthora infestans is a damaging crop pathogen and a model organism to study plant-pathogen interactions. We report the discovery of a family of copper-dependent lytic polysaccharide monooxygenases (LPMOs) in plant pathogenic oomycetes and its role in plant infection by P. infestans We show that LPMO-encoding genes are up-regulated early during infection and that the secreted enzymes oxidatively cleave the backbone of pectin, a charged polysaccharide in the plant cell wall. The crystal structure of the most abundant of these LPMOs sheds light on its ability to recognize and degrade pectin, and silencing the encoding gene in P. infestans inhibits infection of potato, indicating a role in host penetration. The identification of LPMOs as virulence factors in pathogenic oomycetes opens up opportunities in crop protection and food security.


Assuntos
Lycopersicon esculentum/parasitologia , Oxigenases de Função Mista/metabolismo , Pectinas/metabolismo , Phytophthora infestans/enzimologia , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , Cobre , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Modelos Moleculares , Oxirredução , Phytophthora infestans/genética , Phytophthora infestans/patogenicidade , Folhas de Planta/parasitologia , Polissacarídeos/metabolismo , Conformação Proteica , Domínios Proteicos , Fatores de Virulência/química , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
3.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068779

RESUMO

Bacillus volatiles to control plant nematodes is a topic of great interest among researchers due to its safe and environmentally friendly nature. Bacillus strain GBSC56 isolated from the Tibet region of China showed high nematicidal activity against M. incognita, with 90% mortality as compared with control in a partition plate experiment. Pure volatiles produced by GBSC56 were identified through gas chromatography and mass spectrometry (GC-MS). Among 10 volatile organic compounds (VOCs), 3 volatiles, i.e., dimethyl disulfide (DMDS), methyl isovalerate (MIV), and 2-undecanone (2-UD) showed strong nematicidal activity with a mortality rate of 87%, 83%, and 80%, respectively, against M. incognita. The VOCs induced severe oxidative stress in nematodes, which caused rapid death. Moreover, in the presence of volatiles, the activity of antioxidant enzymes, i.e., SOD, CAT, POD, and APX, was observed to be enhanced in M. incognita-infested roots, which might reduce the adverse effect of oxidative stress-induced after infection. Moreover, genes responsible for plant growth promotion SlCKX1, SlIAA1, and Exp18 showed an upsurge in expression, while AC01 was downregulated in infested plants. Furthermore, the defense-related genes (PR1, PR5, and SlLOX1) in infested tomato plants were upregulated after treatment with MIV and 2-UD. These findings suggest that GBSC56 possesses excellent biocontrol potential against M. incognita. Furthermore, the study provides new insight into the mechanism by which GBSC56 nematicidal volatiles regulate antioxidant enzymes, the key genes involved in plant growth promotion, and the defense mechanism M. incognita-infested tomato plants use to efficiently manage root-knot disease.


Assuntos
Bacillus/genética , Resistência à Doença/genética , Lycopersicon esculentum/genética , Tylenchoidea/patogenicidade , Animais , Antinematódeos/metabolismo , Bacillus/metabolismo , China , Cromatografia Gasosa-Espectrometria de Massas , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/parasitologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Tylenchoidea/genética , Compostos Orgânicos Voláteis/metabolismo
4.
Int J Mol Sci ; 22(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946385

RESUMO

Radopholus similis is a migratory endoparasitic nematode that is extremely harmful to host plants. Venom allergen-like proteins (VAPs) are members of the cysteine-rich secretory protein family that are widely present in plants and animals. In this study, we cloned a VAP gene from R. similis, designated as RsVAP. RsVAP contains an open reading frame of 1089 bp encoding 362 amino acids. RsVAP is specifically expressed in the esophageal gland, and the expression levels of RsVAP are significantly higher in juveniles than in other life stages of R. similis. This expression pattern of RsVAP was consistent with the biological characteristics of juveniles of R. similis, which have the ability of infection and are the main infection stages of R. similis. The pathogenicity and reproduction rate of R. similis in tomato was significantly attenuated after RsVAP was silenced. In tobacco leaves transiently expressing RsVAP, the pathogen-associated molecular pattern-triggered immunity (PTI) induced by a bacterial flagellin fragment (flg22) was inhibited, while the cell death induced by two sets of immune elicitors (BAX and Gpa2/RBP-1) was repressed. The RsVAP-interacting, ras-related protein RABA1d (LeRabA1d) was identified in tomato hosts by yeast two-hybrid and co-immunoprecipitation assays. RsVAP may interact with LeRabA1d to affect the host defense response, which in turn facilitates nematode infection. This study provides the first evidence for the inhibition of plant defense response by a VAP from migratory plant-parasitic nematodes, and, for the first time, the target protein of R. similis in its host was identified.


Assuntos
Proteínas de Helminto/imunologia , Lycopersicon esculentum/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal , Tabaco/imunologia , Tylenchida/imunologia , Animais , Interações Hospedeiro-Parasita , Lycopersicon esculentum/parasitologia , Doenças das Plantas/parasitologia , Tabaco/parasitologia , Tylenchida/fisiologia
5.
Mol Plant Pathol ; 22(5): 495-507, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33709540

RESUMO

TAXONOMY: Phylum Nematoda; class Chromadorea; order Rhabditida; suborder Tylenchina; infraorder Tylenchomorpha; superfamily Tylenchoidea; family Heteroderidae; subfamily Heteroderinae; Genus Globodera. BIOLOGY: Potato cyst nematodes (PCN) are biotrophic, sedentary endoparasitic nematodes. Invasive (second) stage juveniles (J2) hatch from eggs in response to the presence of host root exudates and subsequently locate and invade the host. The nematodes induce the formation of a large, multinucleate syncytium in host roots, formed by fusion of up to 300 root cell protoplasts. The nematodes rely on this single syncytium for the nutrients required to develop through a further three moults to the adult male or female stage. This extended period of biotrophy-between 4 and 6 weeks in total-is almost unparalleled in plant-pathogen interactions. Females remain at the root while adult males revert to the vermiform body plan of the J2 and leave the root to locate and fertilize the female nematodes. The female body forms a cyst that contains the next generation of eggs. HOST RANGE: The host range of PCN is limited to plants of the Solanaceae family. While the most economically important hosts are potato (Solanum tuberosum), tomato (Solanum lycopersicum), and aubergine (Solanum melongena), over 170 species of Solanaceae are thought to be potential hosts for PCN (Sullivan et al., 2007). DISEASE SYMPTOMS: Symptoms are similar to those associated with nutrient deficiency, such as stunted growth, yellowing of leaves and reduced yields. This absence of specific symptoms reduces awareness of the disease among growers. DISEASE CONTROL: Resistance genes (where available in suitable cultivars), application of nematicides, crop rotation. Great effort is put into reducing the spread of PCN through quarantine measures and use of certified seed stocks. USEFUL WEBSITES: Genomic information for PCN is accessible through WormBase ParaSite.


Assuntos
Genoma Helmíntico/genética , Interações Hospedeiro-Parasita , Lycopersicon esculentum/parasitologia , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , Tylenchoidea/fisiologia , Animais , Resistência à Doença/genética , Feminino , Genômica , Especificidade de Hospedeiro/genética , Lycopersicon esculentum/genética , Lycopersicon esculentum/imunologia , Masculino , Doenças das Plantas/prevenção & controle , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/parasitologia , Raízes de Plantas/genética , Raízes de Plantas/imunologia , Raízes de Plantas/parasitologia , Solanum tuberosum/genética , Solanum tuberosum/imunologia , Tylenchoidea/genética
6.
PLoS One ; 16(2): e0247325, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606799

RESUMO

The human enteric bacterial pathogen Salmonella enterica causes approximately 1.35 million cases of food borne illnesses annually in the United States. Of these salmonellosis cases, almost half are derived from the consumption of fresh, raw produce. Although epiphytic S. enterica populations naturally decline in the phyllosphere, a subset of phytophagous insects have recently been identified as biological multipliers, consequently facilitating the growth of bacterial populations. We investigated whether tomato leaves with macroscopic feeding damage, caused by infestation of adult Western flower thrips (Frankliniella occidentalis), support higher S. enterica populations. To explore this hypothesis, we assessed S. enterica populations in response to thrips feeding by varying insect density, plant age, and the gender of the insect. As a reference control, direct leaf damage analogous to thrips feeding was also evaluated using directed, hydraulic pressure. In a supplementary set series of experiments, groups of F. occidentalis infested tomato plants were later inoculated with S. enterica to determine how prior insect infestation might influence bacterial survival and persistence. Following an infestation period, leaves visibly damaged by adult F. occidentalis supported significantly higher S. enterica populations and resulted in greater amounts of electrolyte leakage (measured as electrical conductivity) than leaves lacking visible feeding damage. Plant age did not significantly influence S. enterica populations or estimates of electrolyte leakage, independent of initial infestation. Additionally, the gender of the insect did not uniquely influence S. enterica population dynamics. Finally, applications of aggressive water bombardment resulted in more electrolyte leakage than leaves damaged by F. occidentalis, yet supported comparable S. enterica populations. Together, this study indicates that F. occidentalis feeding is one of the many potential biological mechanisms creating a more habitable environment for S. enterica.


Assuntos
Lycopersicon esculentum/parasitologia , Salmonella enterica/fisiologia , Tisanópteros/fisiologia , Ração Animal , Animais , Comportamento Animal , Feminino , Microbiologia de Alimentos , Lycopersicon esculentum/microbiologia , Masculino , Viabilidade Microbiana , Folhas de Planta/microbiologia , Folhas de Planta/parasitologia , Tisanópteros/microbiologia
7.
BMC Plant Biol ; 21(1): 114, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627099

RESUMO

BACKGROUND: The tomato psyllid, Bactericera cockerelli Sulc (Hemiptera: Triozidae), is a pest of solanaceous crops such as tomato (Solanum lycopersicum L.) in the U.S. and vectors the disease-causing pathogen 'Candidatus Liberibacter solanacearum'. Currently, the only effective strategies for controlling the diseases associated with this pathogen involve regular pesticide applications to manage psyllid population density. However, such practices are unsustainable and will eventually lead to widespread pesticide resistance in psyllids. Therefore, new control strategies must be developed to increase host-plant resistance to insect vectors. For example, expression of constitutive and inducible plant defenses can be improved through selection. Currently, it is still unknown whether psyllid infestation has any lasting consequences on tomato plant defense or tomato plant gene expression in general. RESULTS: In order to characterize the genes putatively involved in tomato defense against psyllid infestation, RNA was extracted from psyllid-infested and uninfested tomato leaves (Moneymaker) 3 weeks post-infestation. Transcriptome analysis identified 362 differentially expressed genes. These differentially expressed genes were primarily associated with defense responses to abiotic/biotic stress, transcription/translation, cellular signaling/transport, and photosynthesis. These gene expression changes suggested that tomato plants underwent a reduction in plant growth/health in exchange for improved defense against stress that was observable 3 weeks after psyllid infestation. Consistent with these observations, tomato plant growth experiments determined that the plants were shorter 3 weeks after psyllid infestation. Furthermore, psyllid nymphs had lower survival rates on tomato plants that had been previously psyllid infested. CONCLUSION: These results suggested that psyllid infestation has lasting consequences for tomato gene expression, defense, and growth.


Assuntos
Hemípteros/crescimento & desenvolvimento , Interações Hospedeiro-Parasita/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/genética , Lycopersicon esculentum/imunologia , Lycopersicon esculentum/parasitologia , Imunidade Vegetal/genética , Animais , Regulação da Expressão Gênica de Plantas , Genes de Plantas
8.
Food Microbiol ; 95: 103704, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33397622

RESUMO

Fresh vegetables are essential components of a healthy and nutritious diet, but if consumed raw without proper washing and/or disinfection, can be important agents of transmission of enteric pathogens. This study aimed to determine the prevalence of zoonotic parasites on vegetables freshly harvested and "ready to eat" vegetables from greengrocers and markets in northwestern Iran. In addition, the effect of cropping system and season on contamination levels were assessed as well as the efficacy of washing procedures to remove parasites from the vegetables. A total of 2757 samples composed of field (n = 1, 600) and "ready to eat" (n = 1157) vegetables were analyzed. Vegetables included leek, parsley, basil, coriander, savory, mint, lettuce, cabbage, radish, dill, spinach, mushroom, carrot, tomato, cucumber and pumpkin. Normal physiological saline washings from 200 g samples were processed using standard parasitological techniques and examined microscopically. A total of 53.14% of vegetable samples obtained from different fields and 18.23% of "ready to eat" vegetables purchased from greengrocers and markets were contaminated with different parasitic organisms including; Entamoeba coli cysts, Giardia intestinalis cysts, Cryptosporidium parvum oocysts, Fasciola hepatica eggs, Dicrocoelium dendriticum eggs, Taenia spp. eggs, Hymenolepis nana eggs, Ancylostoma spp. eggs, Toxocara cati eggs, Toxocara canis eggs, Strongyloides stercoralis larvae, and Ascaris lumbricoides eggs. In both field and "ready to eat" vegetables, the highest parasitic contamination was observed in lettuce with a rate of 91.1% and 55.44%, respectively. The most common parasitic organism was Fasciola hepatica. A seasonal difference in contamination with parasitic organisms was found for field and "ready to eat" vegetables (P < 0.05). There was a significant difference in the recovery of parasitic organisms depending on the washing method with water and dishwashing liquid being the least effective. Proper washing of vegetables is imperative for a healthy diet as the results of this study showed the presence of zoonotic parasites from field and ready to eat vegetables in Iran.


Assuntos
Zoonoses Bacterianas/parasitologia , Contaminação de Alimentos/análise , Parasitos/isolamento & purificação , Verduras/parasitologia , Animais , Cucumis sativus/parasitologia , Manipulação de Alimentos , Humanos , Irã (Geográfico) , Alface/parasitologia , Lycopersicon esculentum/parasitologia , Parasitos/classificação , Parasitos/genética , Parasitos/crescimento & desenvolvimento , Petroselinum/parasitologia
9.
PLoS One ; 16(1): e0239958, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33428626

RESUMO

Insect pests cause serious damage in crop production, and various attempts have been made to produce insect-resistant crops, including the expression of genes for proteins with anti-herbivory activity, such as Bt (Bacillus thuringiensis) toxins. However, the number of available genes with sufficient anti-herbivory activity is limited. MLX56 is an anti-herbivory protein isolated from the latex of mulberry plants, and has been shown to have strong growth-suppressing activity against the larvae of a variety of lepidopteran species. As a model of herbivore-resistant plants, we produced transgenic tomato lines expressing the gene for MLX56. The transgenic tomato lines showed strong anti-herbivory activities against the larvae of the common cutworm, Spodoptera litura. Surprisingly, the transgenic tomato lines also exhibited strong activity against the attack of western flower thrips, Frankliniera occidentalis. Further, growth of the hadda beetle, Henosepilachna vigintioctopunctata, fed on leaves of transgenic tomato was significantly retarded. The levels of damage caused by both western flower thrips and hadda beetles were negligible in the high-MLX56-expressing tomato line. These results indicate that introduction of the gene for MLX56 into crops can enhance crop resistance against a wide range of pest insects, and that MLX56 can be utilized in developing genetically modified (GM) pest-resistant crops.


Assuntos
Expressão Gênica , Látex , Lycopersicon esculentum , Morus/genética , Proteínas de Plantas , Plantas Geneticamente Modificadas , Animais , Bacillus thuringiensis , Insetos , Lycopersicon esculentum/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/parasitologia , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/parasitologia
10.
Sci Rep ; 11(1): 326, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431951

RESUMO

Throughout infection, plant-parasitic nematodes activate a complex host defense response that will regulate their development and aggressiveness. Oxylipins-lipophilic signaling molecules-are part of this complex, performing a fundamental role in regulating plant development and immunity. At the same time, the sedentary root-knot nematode Meloidogyne spp. secretes numerous effectors that play key roles during invasion and migration, supporting construction and maintenance of nematodes' feeding sites. Herein, comprehensive oxylipin profiling of tomato roots, performed using LC-MS/MS, indicated strong and early responses of many oxylipins following root-knot nematode infection. To identify genes that might respond to the lipidomic defense pathway mediated through oxylipins, RNA-Seq was performed by exposing Meloidogyne javanica second-stage juveniles to tomato protoplasts and the oxylipin 9-HOT, one of the early-induced oxylipins in tomato roots upon nematode infection. A total of 7512 differentially expressed genes were identified. To target putative effectors, we sought differentially expressed genes carrying a predicted secretion signal peptide. Among these, several were homologous with known effectors in other nematode species; other unknown, potentially secreted proteins may have a role as root-knot nematode effectors that are induced by plant lipid signals. These include effectors associated with distortion of the plant immune response or manipulating signal transduction mediated by lipid signals. Other effectors are implicated in cell wall degradation or ROS detoxification at the plant-nematode interface. Being an integral part of the plant's defense response, oxylipins might be placed as important signaling molecules underlying nematode parasitism.


Assuntos
Comunicação Celular , Interações Hospedeiro-Parasita , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Oxilipinas/metabolismo , Transdução de Sinais , Tylenchoidea/fisiologia , Animais , Lycopersicon esculentum/citologia
11.
Sci Rep ; 11(1): 1153, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441896

RESUMO

The tomato pinworm Tuta absoluta (Lepidoptera: Gelechuidae) is native to South America and has now become the main tomato pest in Europe, Africa and Asia. The wide range of host plants attacked by this pest has been reported as one of the main reasons for the success of this important insect species. However, the information currently available on the biological performance of T. absoluta on Solanaceae has been obtained from a limited number of host species. The Solanaceae family is composed of thousands of species, many of which are potential hosts for T. absoluta. Our results showed that the highest oviposition rates occurred on cultivated tomato plants, potato and wild tomato. The lowest rates occurred on "gilo", "jurubeba", green pepper and pepper. The highest survival rates of the immature stages occurred on potato and the lowest on pepper, green pepper and "jurubeba". Female fertility, following infestation of the different plant species, was highest for insects that developed on tomato or potato and the lowest rates were seen on American black nightshade. The net reproductive rate and the intrinsic growth rate were highest on potato and tomato. Cluster analysis grouped tomato and potato as highly susceptible to attack, American black nightshade, juá, eggplant, gilo and wild tomato as moderately susceptible, whilst pepper, green pepper and jurubeba were categorized as resistant to T. absoluta. These results clearly demonstrate that the choice of solanaceous host plant species has a direct impact on the fitness parameters of the tomato pinworm as well as survival potential, dispersion and establishment at new sites. These results are important for the planning of integrated pest management strategies.


Assuntos
Lepidópteros/anatomia & histologia , Lycopersicon esculentum/parasitologia , Oviposição , Solanaceae/parasitologia , Animais , Feminino , Fertilidade , Espécies Introduzidas , Lepidópteros/fisiologia , Masculino , Doenças das Plantas/parasitologia
12.
Mol Plant Microbe Interact ; 34(3): 309-318, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33258418

RESUMO

Phytophthora spp. secrete vast arrays of effector molecules during infection to aid in host colonization. The crinkling and necrosis (CRN) protein family forms an extensive repertoire of candidate effectors that accumulate in the host nucleus to perturb processes required for immunity. Here, we show that CRN12_997 from Phytophthora capsici binds a TCP transcription factor, SlTCP14-2, to inhibit its immunity-associated activity against Phytophthora spp. Coimmunoprecipitation and bimolecular fluorescence complementation studies confirm a specific CRN12_997-SlTCP14-2 interaction in vivo. Coexpression of CRN12_997 specifically counteracts the TCP14-enhanced immunity phenotype, suggesting that CRN mediated perturbation of SlTCP14-2 function. We show that SlTCP14-2 associates with nuclear chromatin and that CRN12_997 diminishes SlTCP14-2 DNA binding. Collectively, our data support a model in which SlTCP14-2 associates with chromatin to enhance immunity. The interaction between CRN12_997 and SlTCP14-2 reduces DNA binding of the immune regulator. We propose that the modulation of SlTCP14-2 chromatin affinity, caused by CRN12-997, enhances susceptibility to P. capsici.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Lycopersicon esculentum , Phytophthora , Receptores de Superfície Celular , Lycopersicon esculentum/parasitologia , Phytophthora/genética , Phytophthora/patogenicidade , Doenças das Plantas/parasitologia , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Virulência/genética
13.
Methods Mol Biol ; 2170: 35-43, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32797449

RESUMO

Laser capture microdissection (LCM) has become a powerful technique that allows analyzing gene expression in specific target cells from complex tissues. Widely used in animal research, still few studies on plants have been carried out. We have applied this technique to the plant-nematode interaction by isolating feeding cells (giant cells; GCs) immersed inside complex swelled root structures (galls) induced by root-knot nematodes. For this purpose, a protocol that combines good morphology preservation with RNA integrity maintenance was developed, and successfully applied to Arabidopsis and tomato galls. Specifically, early developing GCs at 3 and 7 days post-infection (dpi) were analyzed; RNA from LCM GCs was amplified and used successfully for microarray assays.


Assuntos
Crioultramicrotomia/métodos , Microdissecção e Captura a Laser/métodos , Lycopersicon esculentum/genética , Lycopersicon esculentum/parasitologia , RNA de Plantas/isolamento & purificação , Animais , Regulação da Expressão Gênica de Plantas , Células Gigantes/metabolismo , Células Gigantes/parasitologia , Interações Hospedeiro-Parasita , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Tylenchoidea/patogenicidade
14.
Sci Rep ; 10(1): 22195, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33335143

RESUMO

Endophytic fungi live within plant tissues without causing any harm to the host, promote its growth, and induce systemic resistance against pests and diseases. To mitigate the challenging concealed feeding behavior of immature stages of Tuta absoluta in both tomato (Solanum lycopersicum) and nightshade (Solanum scabrum) host plants, 15 fungal isolates were assessed for their endophytic and insecticidal properties. Twelve isolates were endophytic to both host plants with varied colonization rates. Host plants endophytically-colonized by Trichoderma asperellum M2RT4, Beauveria bassiana ICIPE 706 and Hypocrea lixii F3ST1 outperformed all the other isolates in reducing significantly the number of eggs laid, mines developed, pupae formed and adults emerged. Furthermore, the survival of exposed adults and F1 progeny was significantly reduced by Trichoderma sp. F2L41 and B. bassiana isolates ICIPE 35(4) and ICIPE 35(15) compared to other isolates. The results indicate that T. asperellum M2RT4, B. bassiana ICIPE 706 and H. lixii F3ST1 have high potential to be developed as endophytic-fungal-based biopesticide for the management of T. absoluta.


Assuntos
Endófitos , Fungos/fisiologia , Interações Hospedeiro-Parasita , Lepidópteros , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/parasitologia , Solanum , Simbiose , Animais , Resistência à Doença
15.
Dokl Biochem Biophys ; 495(1): 329-333, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33368045

RESUMO

New data on the effect of colloidal silicon nanoparticles on the content of nutrients and photosynthetic pigments in tomato plants invaded by root-knot nematode Meloidogyne incognita are presented. Foliar treatment of plants with colloidal solutions of silicon nanoparticles at concentrations of 0.5 and 1.0 µg/mL revealed an increase in the content of photosynthetic pigments and a number of biogenic elements (P, Mg, K, S, and Fe) in tomato leaves, indicating an improvement in the physiological state of the invaded plants. The stimulating effect of nanosilicon on the development and growth of plants and the inhibiting effect on the susceptibility of plants by nematodes and the morpho-physiological parameters of the parasite is shown.


Assuntos
Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/parasitologia , Nanopartículas/administração & dosagem , Pigmentos Biológicos/metabolismo , Doenças das Plantas/prevenção & controle , Silício/farmacologia , Oligoelementos/metabolismo , Animais , Lycopersicon esculentum/metabolismo , Nanopartículas/química , Fotossíntese/efeitos dos fármacos , Doenças das Plantas/parasitologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/parasitologia , Silício/química , Tylenchoidea/isolamento & purificação
16.
Int J Mol Sci ; 21(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317090

RESUMO

Defensins are small and rather ubiquitous cysteine-rich anti-microbial peptides. These proteins may act against pathogenic microorganisms either directly (by binding and disrupting membranes) or indirectly (as signaling molecules that participate in the organization of the cellular defense). Even though defensins are widespread across eukaryotes, still, extensive nucleotide and amino acid dissimilarities hamper the elucidation of their response to stimuli and mode of function. In the current study, we screened the Solanum lycopersicum genome for the identification of defensin genes, predicted the relating protein structures, and further studied their transcriptional responses to biotic (Verticillium dahliae, Meloidogyne javanica, Cucumber Mosaic Virus, and Potato Virus Y infections) and abiotic (cold stress) stimuli. Tomato defensin sequences were classified into two groups (C8 and C12). Our data indicate that the transcription of defensin coding genes primarily depends on the specific pathogen recognition patterns of V. dahliae and M. javanica. The immunodetection of plant defensin 1 protein was achieved only in the roots of plants inoculated with V. dahliae. In contrast, the almost null effects of viral infections and cold stress, and the failure to substantially induce the gene transcription suggest that these factors are probably not primarily targeted by the tomato defensin network.


Assuntos
Defensinas/genética , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Animais , Resposta ao Choque Frio , Defensinas/metabolismo , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/parasitologia , Proteínas de Plantas/metabolismo , Ativação Transcricional , Tylenchoidea/patogenicidade , Verticillium/patogenicidade
17.
Int J Mol Sci ; 21(22)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187355

RESUMO

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an important agricultural pest worldwide. Uridine diphosphate (UDP)-glucuronosyltransferases (UGTs) are one of the largest and most ubiquitous groups of proteins. Because of their role in detoxification, insect UGTs are attracting increasing attention. In this study, we identified and analyzed UGT genes in B. tabaci MEAM1 to investigate their potential roles in host adaptation and reproductive capacity. Based on phylogenetic and structural analyses, we identified 76 UGT genes in the B. tabaci MEAM1 genome. RNA-seq and real-time quantitative PCR (RT-qPCR) revealed differential expression patterns of these genes at different developmental stages and in association with four host plants (cabbage, cucumber, cotton and tomato). RNA interference results of selected UGTs showed that, when UGT352A1, UGT352B1, and UGT354A1 were respectively silenced by feeding on dsRNA, the fecundity of B. tabaci MEAM1 was reduced, suggesting that the expressions of these three UGT genes in this species may be associated with host-related fecundity. Together, our results provide detailed UGTs data in B.tabaci and help guide future studies on the mechanisms of host adaptation by B.tabaci.


Assuntos
Glucuronosiltransferase/genética , Hemípteros/genética , Difosfato de Uridina/genética , Animais , Brassica/parasitologia , Cucumis sativus/parasitologia , Estudo de Associação Genômica Ampla , Gossypium/parasitologia , Proteínas de Insetos/genética , Lycopersicon esculentum/parasitologia , Filogenia , RNA de Cadeia Dupla/genética
18.
Sci Rep ; 10(1): 19968, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203960

RESUMO

Tomato (Solanum Lycopersicum L.) is an important vegetable crop that belongs to the family Solanaceae. Root-knot nematodes reflect the highly critical economically damaging genera of phytoparasitic nematodes on tomato plants. In this study, the eco-nematicide activity of freshwater green macroalga Cladophora glomerata aqueous extract and their synthesized silver nanoparticles (Ag-NPs) against root-knot nematodes Meloidogyne javanica was investigated on tomato plants. The formation and chemical structure of Ag-NPs was examined. The aqueous extract from C. glomerata was applied against the root-knot nematodes besides the biosynthesized green silver nanoparticles with 100, 75, 50, and 25% (S, S/2, S/3, S/4) concentrations. To investigate the plant response toward the Green Synthesized Silver Nanoparticles (GSNPs) treatment, expression profiling of Phenylalanine Ammonia-Lyase (PAL), Poly Phenol Oxidase (PPO), and Peroxidase (POX) in tomato were examined using Quantitative Real-Time PCR (Q-PCR). The results indicated that GSNPs from C. glomerata exhibited the highest eco-nematicide activity in the laboratory bioassay on egg hatchability and juveniles (J2S) mortality of M. javanica compared with the chemical commercial nematicide Rugby 60%. Also, results showed a significant reduction in galls number, egg masses, females per root system/plant, and mortality of juveniles. The results of PAL and PPO enzyme expression for the control plants remained relatively stable, while the plant inoculated with nematode M. javanica as well as the activity of genes in scope was increased from 14 to 28 Days after Nematode Inoculation (DANI). These activities were improved in inoculated plants and treated with C. glomerata extract and their green syntheses of Ag-NPs and the other plants treated with Rugby 60% (4 mL/L). The greatest activities of the three enzymes were evident after 14 days after the nematode inoculation. It can be concluded that the green synthesized nanoparticles using C. glomerata could be used as potent nematicides against M. javanica which induces the immune system to defend against nematode infection.


Assuntos
Antinematódeos/farmacologia , Clorófitas/química , Lycopersicon esculentum/parasitologia , Nanopartículas Metálicas/administração & dosagem , Extratos Vegetais/farmacologia , Prata/administração & dosagem , Tylenchoidea/efeitos dos fármacos , Animais , Feminino , Lycopersicon esculentum/metabolismo , Masculino , Peroxidases/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia
19.
Dokl Biochem Biophys ; 494(1): 266-269, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33119831

RESUMO

Salicylic acid (SA) induces the mechanism of the plant defence and plays a role in plant -pathogen interactions. Following the nematode infection, effects of SA treatment on plant weights and the expression of pathogen related gene have not been fully understood. The present study was aimed to determine the effects of SA treatment on the expression Pathogenesis related 1 gene (PR1 gene) and alteration on plant parameters in tomatoes (Solanum lycopersicum). Plant seedlings were dripped within the SA solution. The expression of PR1 gene achieved using RT-PCR at 1, 3, 7, 14, 21-days post infection (dpi) with Meloidogyne incognita. Upregulation of PR1 gene was determined in early (1 dpi) and late (21 dpi). SA treatment and nematode infection altered plant parameters. SA treatment increased the plant defence mechanisms in tomato against Meloidogyne incognita.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Doenças das Plantas/genética , Ácido Salicílico/farmacologia , Tylenchoidea/fisiologia , Animais , Anti-Infecciosos/farmacologia , Lycopersicon esculentum/genética , Lycopersicon esculentum/parasitologia , Doenças das Plantas/parasitologia , Transdução de Sinais
20.
Nat Commun ; 11(1): 5299, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082345

RESUMO

Parasitic plants of the genus Cuscuta penetrate shoots of host plants with haustoria and build a connection to the host vasculature to exhaust water, solutes and carbohydrates. Such infections usually stay unrecognized by the host and lead to harmful host plant damage. Here, we show a molecular mechanism of how plants can sense parasitic Cuscuta. We isolated an 11 kDa protein of the parasite cell wall and identified it as a glycine-rich protein (GRP). This GRP, as well as its minimal peptide epitope Crip21, serve as a pathogen-associated molecular pattern and specifically bind and activate a membrane-bound immune receptor of tomato, the Cuscuta Receptor 1 (CuRe1), leading to defense responses in resistant hosts. These findings provide the initial steps to understand the resistance mechanisms against parasitic plants and further offer great potential for protecting crops by engineering resistance against parasitic plants.


Assuntos
Parede Celular/metabolismo , Cuscuta/metabolismo , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Doenças das Plantas/parasitologia , Proteínas de Plantas/metabolismo , Parede Celular/genética , Cuscuta/genética , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Parasita , Lycopersicon esculentum/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética
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