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1.
Microbiol Res ; 266: 127242, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36356349

RESUMO

Pochonia chlamydosporia is a soil-dwelling fungus and biological control agent of nematodes, active ingredient in commercial bionematicides. The fungus is also endophytically associated with the roots of several plant species, promoting their growth and inducing systemic resistance. In this study, different pathways and tomato defense metabolites were studied to identify mechanisms induced by P. chlamydosporia that contribute to the control of Meloidogyne javanica, at early and late developmental stages. Some defense responses activated by the fungus appeared related to the nematode life cycle. Among the evaluated biochemical analysis, root colonization of P. chlamydosporia showed an increase in the concentration of phenolic compounds, such as chlorogenic acid. In addition, the expression of some host plant genes was also modified. The interaction of the fungus with roots parasitized by M. javanica resulted in the highest expression of Phenylalanine Ammonia-Lyase (PAL), Chalcone synthase (LECHS 2), and Protease Inhibitor (PI1) genes at 24 days post-inoculation. At the second sampling time (44 days), there was an increase in the expression of the Respiratory Burst Oxidase Homolog (RBOH) gene. Fungus reduced the expression of the ACC-oxidase and Pathogenesis-Related Proteins 1 (PR-1) genes in roots. Moreover, P. chlamydosporia inoculation changed metabolites and phytohormone profiles of the gall formed by M. javanica. Plant defense response appeared to involve the jasmonic acid and phytosphingosine cascades. With this analysis, it was possible to propose new molecular mechanisms induced by the fungus that contribute to the control of M. javanica.


Assuntos
Hypocreales , Lycopersicon esculentum , Tylenchoidea , Animais , Tylenchoidea/microbiologia , Lycopersicon esculentum/microbiologia , Raízes de Plantas/microbiologia
2.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362334

RESUMO

We investigated gut bacteria from three insect species for the presence of plant growth properties (PGP). Out of 146 bacterial strains obtained from 20 adult specimens of Scolytidae sp., 50 specimens of Oulema melanopus, and 150 specimens of Diabrotica virgifera, we selected 11 strains displaying the following: PGP, phosphate solubility, production of cellulase, siderophore, lipase, protease, and hydrogen cyanide. The strains were tested for growth promotion ability on tomato (Lycopersicon esculentum) plants. Each strain was tested individually, and all strains were tested together as a bacterial consortium. Tomato fruit yield was compared with the negative control. The plants treated with bacterial consortium showed a significant increase in fruit yield, in both number of fruits (+41%) and weight of fruits (+44%). The second highest yield was obtained for treatment with Serratia liquefaciens Dv032 strain, where the number and weight of yielded fruits increased by 35% and 30%, respectively. All selected 11 strains were obtained from Western Corn Rootworm (WCR), Diabrotica virgifera. The consortium comprised: Ewingella americana, Lactococcus garvieae, L. lactis, Pseudomonas putida, Serratia liquefaciens, and S. plymuthica. To our knowledge, this is the first successful application of D. virgifera gut bacteria for tomato plant growth stimulation that has been described.


Assuntos
Besouros , Lycopersicon esculentum , Pseudomonas putida , Animais , Lycopersicon esculentum/microbiologia , Insetos , Zea mays
3.
Arch Microbiol ; 204(11): 687, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36324009

RESUMO

Antimicrobial proteins and peptides are an alternative to current antibiotics. Here, we report an antimicrobial activity in a low-molecular-weight protein secreted naturally by Streptomyces lividans TK24 when glucose or glycerol were used as carbon sources. The antimicrobial activity was demonstrated against Bacillus subtilis, Bacillus cereus, Kokuria rhizophila, Clostridium sporogenes and Clavibacter michiganensis, causal pathogen of tomato bacterial canker; one of the most destructive bacterial diseases of this crop. The protein fraction with antimicrobial activity was identified and quantified by LC-MS/MS. From a total of 155 proteins, 11 were found to be within the range of 11.3-13.9 kDa of which four proteins were selected by functional analysis as possibly responsible for the antimicrobial activity. Protein fractionation, correlation analysis between antimicrobial activity and abundance of selected proteins, as well as transcriptional expression analysis, indicate that 50S ribosomal protein L19 is the main candidate responsible for antimicrobial activity.


Assuntos
Anti-Infecciosos , Lycopersicon esculentum , Micrococcaceae , Streptomyces lividans , Cromatografia Líquida , Espectrometria de Massas em Tandem , Lycopersicon esculentum/microbiologia , Anti-Infecciosos/farmacologia
4.
Curr Microbiol ; 79(12): 380, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329344

RESUMO

Tomato is affected by various diseases which cause economical loss to the farming community. In the present study, twenty isolates of Bacillus sp. were isolated from the rhizosphere of tomato and screened against soil-borne pathogens viz., Pythium aphanidermatum No.5, Fusarium oxysporum f. sp. lycopersici No. FOL-8, and Sclerotium rolfsii No. S-MK in tomato. The results revealed that three Bacillus sp. viz., BST8, BST18, and BST19 were promising in reducing the mycelial growth of the pathogens (up to 48% reduction) when compared to control under in vitro. The isolates possessed antimicrobial peptide genes which were detected through PCR. Novel compounds and secondary metabolites responsible for antifungal action were identified through GC-MS and FTIR analysis. Endospores have been isolated from the Bacillus sp. BST18 and standardized for the development of formulation. Pot culture experiment revealed sequential application of endospore-based bioformulation as seed treatment, (10 ml/kg), seedling dip (10 ml/lit), soil application on 30 days (100 ml/pot) along with foliar spray (0.2%) on 60 days recorded the lowest disease incidence of wilt (9.5%), and collar rot (11.5%) as against 65.5% and 75%, respectively, in the inoculated control. Field experiments revealed sequential application of endospore-based formulation of Bacillus sp. BST 18 as seed treatment, (10 ml/kg), seedling dip (10 ml/lit), soil application (400 ml/acre) at 30 days after transplantation (DAT) along with foliar spray (0.2%) on 60 DAT recorded the lowest wilt disease incidence of 15.97 &17.07 percent as against 49.77 & 51.10 percent in the control.


Assuntos
Bacillus , Fusarium , Lycopersicon esculentum , Lycopersicon esculentum/microbiologia , Bacillus/genética , Bacillus/metabolismo , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Solo , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Plântula
5.
Biochem Biophys Res Commun ; 634: 203-210, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36274333

RESUMO

Long noncoding RNAs (lncRNAs) have attracted widespread attention because of their meaningful roles in various plant biological processes. However, the potential functions of lncRNAs in the plant-beneficial microorganism interactions have not been fully explored. Arbuscular mycorrhiza (AM) symbiosis is accompanied by the systemic induction of defense responses in the host leaves. In the present study, we globally profiled lncRNA expression and explored their potential regulatory roles in AM fungi-inoculated tomato leaves. Among 851 differentially expressed lncRNAs, a novel lncRNA (lncRNA69908) that was significantly downregulated in the leaves of AM fungi inoculated tomato, affected tomato resistance after pathogen infection. One of the competing endogenous RNA networks, lncRNA69908-sly-miR319c, was verified by using a coexpression system. Silencing of lncRNA69908 or overexpression of sly-miR319c enhanced tomato resistance to Phytophthora infestans, whereas overexpression of lncRNA69908 decreased the reactive oxygen species scavenging. As above, we speculated that lncRNA69908 may be involved in mycorrhiza-induced defense responses. Our findings can broaden the knowledge on the potential regulatory roles of ncRNAs in AM symbiosis.


Assuntos
Lycopersicon esculentum , Micorrizas , RNA Longo não Codificante , Lycopersicon esculentum/microbiologia , Resistência à Doença/genética , RNA Longo não Codificante/genética , Micorrizas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas
6.
Appl Environ Microbiol ; 88(22): e0133022, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36314834

RESUMO

The physiology of plant hosts can be dramatically altered by phytopathogens. Xanthomonas hortorum pv. gardneri is one such pathogen that creates an aqueous niche within the leaf apoplast by manipulating the plant via the transcription activator-like effector AvrHah1. Simultaneous immigration of X. hortorum pv. gardneri and Salmonella enterica to healthy tomato leaves results in increased survival of S. enterica as Xanthomonas infection progresses. However, the fate of S. enterica following arrival on actively infected leaves has not been examined. We hypothesized that the water soaking caused by X. hortorum pv. gardneri could facilitate the ingression of S. enterica into the apoplast and that this environment would be conducive for growth. We found that an altered apoplast, abiotically water congested or Xanthomonas infected and water-soaked, enabled surface S. enterica to passively localize to the protective apoplast and facilitated migration of S. enterica to distal sites within the aqueous apoplast. avrHah1 contributed to the protection and migration of S. enterica early in X. hortorum pv. gardneri infection. Xanthomonas-infected apoplasts facilitated prolonged survival and promoted S. enterica replication compared to the case with healthy apoplasts. Access to an aqueous apoplast in general protects S. enterica from immediate exposure to irradiation, whereas the altered environment created by Xanthomonas infection provides growth-conducive conditions for S. enterica. Overall, we have characterized an ecological relationship in which host infection converts an unreachable niche to a habitable environment. IMPORTANCE Bacterial spot disease caused by Xanthomonas species devastates tomato production worldwide. Salmonellosis outbreaks from consumption of raw produce have been linked to the arrival of Salmonella enterica on crop plants in the field via contaminated irrigation water. Considering that Xanthomonas is difficult to eradicate, it is highly likely that S. enterica arrives on leaves precolonized by Xanthomonas with infection under way. Our study demonstrated that infection and disease fundamentally alter the leaf, resulting in redistribution and change in abundance of a phyllosphere bacterial member. These findings contribute to our understanding of how S. enterica manages to persist on leaf tissue despite lacking the ability to liberate nutrients from plant cells. More broadly, this study reveals a mechanism by which physiochemical changes to a host environment imposed by a plant pathogen can convert an uninhabitable leaf environment into a hospitable niche for selected epiphytic microbes.


Assuntos
Lycopersicon esculentum , Salmonella enterica , Xanthomonas , Xanthomonas/fisiologia , Lycopersicon esculentum/microbiologia , Plantas , Água , Doenças das Plantas/microbiologia
7.
Int J Mol Sci ; 23(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36142825

RESUMO

Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (Fol) is a common disease that affects tomatoes, which can cause the whole plant to wilt and seriously reduce the production of tomatoes in greenhouses. In this study, the morphological indexes, photosynthetic performance and incidence rate of NSY50 under Fol infection were evaluated. It was found that NSY50 could improve the growth of tomato seedlings and significantly reduce the incidence rate of Fusarium wilt. However, the molecular mechanism of NSY50 that induces resistance to Fusarium wilt is still unclear. We used transcriptomic methods to analyze NSY50-induced resistance to Fol in tomatoes. The results showed that plant defense related genes, such as PR and PAL, were highly expressed in tomato seedlings pretreated with NSY50. At the same time, photosynthetic efficiency, sucrose metabolism, alkaloid biosynthesis and terpene biosynthesis were significantly improved, which played a positive role in reducing the damage caused by Fol infection and enhancing the disease tolerance of seedlings. Through transgenic validation, we identified an important tomato NAC transcription factor, SlNAP1, which was preliminarily confirmed to be effective in relieving the detrimental symptoms induced by Fol. Our findings reveal that P. polymyxa NSY50 is an effective plant-growth-promoting rhizosphere bacterium and also a biocontrol agent of soil-borne diseases, which can significantly improve the resistance of tomato to Fusarium wilt.


Assuntos
Alcaloides , Fusarium , Lycopersicon esculentum , Fusarium/genética , Perfilação da Expressão Gênica , Lycopersicon esculentum/genética , Lycopersicon esculentum/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Plântula/genética , Solo , Sacarose , Terpenos , Fatores de Transcrição/genética , Transcriptoma
8.
Arch Microbiol ; 204(10): 629, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115881

RESUMO

This work aims at exploring an antagonistic actinobacterial strain isolated from the roots of Ziziphus lotus in bioformulation processes and the biocontrol of Rhizoctonia solani damping-off of tomato seedlings. The strain Streptomyces caeruleatus ZL-2 was investigated for the principal in vitro biocontrol mechanisms and then formulated in three different biofungicides: wettable talcum powder (WTP), sodium alginate propagules (SAP) and clay sodium alginate propagules (CAP). Compared to a marketed control products (Serenade® and Acil 060FS®), the formulated biofungicides were investigated against the R. solani damping-off of tomato cv. Aïcha seedlings. The strain ZL-2 produced chitinases, cellulases, ß-1,3-glucanases, cyanhydric acid and siderophores. It also showed strong antagonistic effect on the mycelial growth of R. solani. Bioautographic and HPLC analysis revealed the production of a single or several co-migrating antifungal compounds. The biofungicide WTP presented an attractive biocontrol effect by significantly reducing the disease severity index (DSI) compared to untreated seeds. No significant differences were obtained compared to the chemical treatment with Acil 060FS®. The viability of spores and biocontrol efficacy of the WTP were confirmed after 1-year storage. Strain ZL-2 has never been reported in the bioformulation of active biofungicides against Rhizoctonia solani damping-off and this work opens up very attractive prospects in the fields of biocontrol and crop improvement.


Assuntos
Celulases , Quitinases , Lycopersicon esculentum , Alginatos , Antifúngicos/farmacologia , Argila , Lycopersicon esculentum/microbiologia , Nitrazepam , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Rhizoctonia , Plântula/microbiologia , Sideróforos , Esporos Fúngicos , Streptomyces , Talco
9.
Microbes Environ ; 37(3)2022.
Artigo em Inglês | MEDLINE | ID: mdl-36104169

RESUMO

The present study investigated the effects of the endophytic fungus, Penicillium pinophilum EU0013 on fruit phytochemical indices and essential trace elements in five tomato cultivars. In a completely randomized design, inoculated and uninoculated seedlings of tomato cultivars (Momotaro, Rodeo, Anaya, Reika, and Cherry) were raised for sixteen weeks in a greenhouse. Fruit fresh weights and root colonization by P. pinophilum were significantly higher in the Rodeo cultivar than in the other cultivars tested. Significant effects of the cultivar, inoculation, and interaction on fruit dry weights were| |observed with higher values in Anaya inoculated with P. pinophilum. Cultivar and inoculation effects were significant for ascorbic acid and soluble sugars in four cultivars, with increases being observed due to the P. pinophilum inoculation. Lycopene levels increased in Rodeo and decreased in Anaya, while ß-carotene levels increased in four cultivars due to the inoculation. Manganese concentrations were significantly increased in Cherry, while iron concentrations were increased in Reika and Cherry. Increases due to the inoculation were observed for gibberellic acids (GA1 and GA4) in Reika and Anaya, whereas decreases were detected in Cherry and Rodeo. Similar results were obtained for abscisic acids (ABA) with increases in Reika and Anaya due to the inoculation. P. pinophilum EU0013 demonstrated the ability to improve the nutritive value of tomato fruits via modulations to phytochemicals in addition to increases in Mn and Fe concentrations, particularly in Cherry and Rodeo. Cultivar responses to the P. pinophilum inoculation are a factor that need to be considered for its use in increasing fruit quality indices in tomato.


Assuntos
Lycopersicon esculentum , Penicillium , Talaromyces , Oligoelementos , Frutas/microbiologia , Lycopersicon esculentum/microbiologia , Penicillium/genética , Compostos Fitoquímicos
10.
Pest Manag Sci ; 78(11): 5002-5013, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36053816

RESUMO

BACKGROUND: Bacterial wilt (BW) caused by Ralstonia solanacearum (RS) is considered as one of the most destructive plant diseases. An avirulent strain of RS, FJAT1458, is a potential biocontrol agent of BW. In this study, the mechanism of FJAT1458 against BW was evaluated. RESULTS: FJAT1458 was tagged with the red fluorescent protein gene, and the resulting strain was named as FJAT1458-RFP. When FJAT1458-RFP and FJAT91-GFP (a virulent strain of RS labelled with the green fluorescent protein gene), were co-inoculated in potted tomato plants, the colonization of FJAT91-GFP reached an almost undetectable level at 7 days post-inoculation (dpi) in the roots and at 9 dpi in rhizosphere soil. When they were co-inoculated in a hydroponic tomato growing system, numbers of the two strains were similar at 3 dpi in the root tissues; however, FJAT91-GFP was not detected at 9 dpi while FJAT1458-RFP maintained 1.77 × 105 CFU g-1 . The inoculation of FJAT1458-RFP alone or combination with FJAT91-GFP significantly increased tomato root activity. Moreover, expression levels of the defense-related genes PR-1a, GLUA, and CHI3 in tomato roots were significantly up-regulated by FJAT1458-RFP and co-inoculation of FJAT1458-RFP and FJAT91-GFP at 5 dpi, compared to the control (water, CK) treatment. Noteworthy, expression levels of GLUA in the treatments of FJAT1458-RFP and FJAT1458-RFP + FJAT91-GFP were 12.22- and 12.05-fold higher than that in the CK at 5 dpi, respectively. CONCLUSIONS: The results suggested that the avirulent strain FJAT1458-RFP could suppress colonization of the virulent strain in tomato roots, and induce tomato plant resistance against BW. © 2022 Society of Chemical Industry.


Assuntos
Lycopersicon esculentum , Ralstonia solanacearum , Proteínas de Fluorescência Verde , Lycopersicon esculentum/genética , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Ralstonia solanacearum/genética , Solo , Água
11.
Pestic Biochem Physiol ; 187: 105199, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36127070

RESUMO

Biocontrol microbes are environment-friendly and safe for humans and animals. To seek biocontrol microbes effective in suppressing tomato gray mold is important for tomato production. Therefore, serial experiments were conducted to characterize the antagonism of Bacillus velezensis HY19, a novel self-isolated biocontrol bacterium, against Botrytis cinerea in vitro and the control on tomato gray mold in greenhouse. This bacterium produced extracellular phosphatase, protease, cellulose and siderophores, and considerably inhibited the growth of B. cinerea. A liquid chromatography-mass spectrometry (LC-MS) detected salicylic acid and numerous antifungal substances present in B. velezensis HY19 fermentation liquid (BVFL). When B. cinerea was grown on potato glucose agar, BVFL crude extract remarkably suppressed the fungal growth and reduced protein content and the activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD). Transcriptome studies showed that BVFL crude extract significantly induced different expression of numerous genes in B. cinerea, most of which were down-regulated. Theses differently expressed genes were involved in the biological process, cell compartment, molecular functions, and metabolisms of glycine, serine, threonine, and sulfur in pathogen hyphae. Thus, this biocontrol bacterium antagonized B. cinerea in multiple ways due to the production of numerous antifungal substances that acted on multiple targets in the cells. BVFL significantly increased antioxidant enzyme activities in tomato leaves and decreased the incidence of tomato gray mold, with the control efficacies of 73.12-76.51%. Taken together, B. velezensis HY19 showed a promising use potential as a powerful bioagent against tomato gray mold.


Assuntos
Lycopersicon esculentum , Ágar/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Bacillus , Catalase , Celulose/farmacologia , Misturas Complexas/farmacologia , Glucose/farmacologia , Glicina/farmacologia , Lycopersicon esculentum/microbiologia , Peptídeo Hidrolases/farmacologia , Monoéster Fosfórico Hidrolases/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Ácido Salicílico/farmacologia , Serina/farmacologia , Sideróforos/farmacologia , Enxofre/farmacologia , Superóxido Dismutase , Treonina/farmacologia
12.
Nat Microbiol ; 7(10): 1547-1557, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36123439

RESUMO

Many bacteria utilize contact-dependent killing machineries to eliminate rivals in their environmental niches. Here we show that the plant root colonizer Pseudomonas putida strain IsoF is able to kill a wide range of soil and plant-associated Gram-negative bacteria with the aid of a type IVB secretion system (T4BSS) that delivers a toxic effector into bacterial competitors in a contact-dependent manner. This extends the range of targets of T4BSSs-so far thought to transfer effectors only into eukaryotic cells-to prokaryotes. Bioinformatic and genetic analyses showed that this killing machine is entirely encoded by the kib gene cluster located within a rare genomic island, which was recently acquired by horizontal gene transfer. P. putida IsoF utilizes this secretion system not only as a defensive weapon to kill bacterial competitors but also as an offensive weapon to invade existing biofilms, allowing the strain to persist in its natural environment. Furthermore, we show that strain IsoF can protect tomato plants against the phytopathogen Ralstonia solanacearum in a T4BSS-dependent manner, suggesting that IsoF can be exploited for pest control and sustainable agriculture.


Assuntos
Lycopersicon esculentum , Pseudomonas putida , Ralstonia solanacearum , Biofilmes , Lycopersicon esculentum/microbiologia , Pseudomonas putida/genética , Solo
13.
Microbiol Spectr ; 10(5): e0118622, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36066253

RESUMO

Propiconazole (PCZ) is a commonly sprayed fungicide against fungal pathogens. Being systemic in action, it reaches subcellular layers and impacts the endophytes. Although PCZ is a fungicide, it is hypothesized to exert an inhibitory effect on the bacterial endophytes. Therefore, this study aims to get an insight into the perturbations caused by the systemically acting antifungal agents PCZ and Bacillus subtilis (W9) and the consequences thereof. The current study compared the 16S rRNA microbial diversity, abundance, and functions of the endophytic bacterial community of tomato in response to PCZ, W9, and PCZ+W9 application. The implications of these treatments on the development of bacterial speck disease by Pseudomonas syringae were also studied. The culturable endophyte population fluctuated after (bio)fungicide application and stabilized by 72 h. At 72 h, the endophyte population was ~3.6 × 103 CFUg-1 in control and ~3.6 × 104 in W9, ~3.0 × 102 in PCZ, and ~5.3 × 103 in PCZ+W9 treatment. A bacterial community analysis showed a higher relative abundance of Bacillales, Burkholderiales, Rhizobiales, Pseudomonadales, and Actinomycetales in the W9 treatment compared with that in the PCZ treatment and control. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis showed enhanced metabolic pathways related to secretion, stress, chemotaxis, and mineral nutrition in the W9 treatment. Disease severity was greater in PCZ than that in the W9 treatment. Disease severity on tomato plants showed strong negative correlations with Sphingomonas (r = -0.860) and Janthinobacterium (r = -0.810), indicating that the natural biocontrol communities are agents of plant resistance to diseases. Outcomes show that systemic chemicals are a potential threat to the nontarget endophytes and that plants became susceptible to disease on endophyte decline; this issue could be overcome by the application of microbial inoculums. IMPORTANCE Endophytes are plant inhabitants acting as its extended genome. The present study highlights the importance of maintaining plant endophytes for sustainable disease resistance in plants. The impact of chemical fungicides and biofungicides was shown on tomato endophytes, in addition to their implications on plant susceptibility to bacterial speck disease. The observations point toward the deleterious effects of systemic pesticide application on endophyte niches that disrupt their diversity and functions compromising plant immunity.


Assuntos
Fungicidas Industriais , Lycopersicon esculentum , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/microbiologia , Bacillus subtilis/genética , RNA Ribossômico 16S/genética , Filogenia , Antifúngicos , Fungicidas Industriais/farmacologia , Fungicidas Industriais/metabolismo , Endófitos/genética , Endófitos/metabolismo , Plantas/microbiologia
14.
Microb Pathog ; 172: 105784, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36122853

RESUMO

Wilt disease, caused by Fusarium oxysporum. f. sp. lycopersici, is a global threat to tomato production that needs to be addressed seriously. The current research envisages the use of two self-compatible Bacillus strains, Bacillus tequilensis PKDN31 and Bacillus licheniformis PKDL10, in a combinatorial approach. The spent supernatant of liquid cultures from strains PKDN31 and PKDL10 showed in vitro antifungal activity against Fusarium sp. attaining an inhibition percentage of 95.33% and 96.54%, respectively. The bacterial isolates lytic activity against Fusarium oxysporum was evaluated by scanning electron microscopic analysis and lytic enzyme production of amylase, lipase, protease and ß-1,3 glucanase. Furthermore, PKDN31 and PKDL10 produced siderophores and had root colonizing ability that enhanced the biocontrol efficiency. Combined in vivo inoculation of Bacillus tequilensis PKDN31 and Bacillus licheniformis PKDL10 on tomato seeds revealed that the strains could induce systemic resistance in tomato against Fusarium oxysporum. f. sp. lycopersici by increasing defence enzymes such as ß-1,3 glucanase, polyphenol oxidase, peroxidase, phenylalanine ammonia-lyase, chitinase, and total phenol accumulations. Pot culture experiments also proved the biocontrol efficacy of the above dual culture supplementation as this treatment displayed a better growth as well as defense against Fusarium challenge compared to the controls. The obtained results suggest that rhizobacterial isolates could be employed as systemic resistance inducers and biocontrol agents in tomato plants to protect against Fusarium wilt disease.


Assuntos
Bacillus licheniformis , Bacillus , Quitinases , Fusarium , Lycopersicon esculentum , Lycopersicon esculentum/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Antifúngicos/farmacologia , Sideróforos , Fenilalanina Amônia-Liase , Fenóis , Catecol Oxidase , Peptídeo Hidrolases , Peroxidases , Lipase , Amilases
15.
FEMS Microbiol Ecol ; 98(10)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36066920

RESUMO

Herein, Bacillus subtilis PBE-8's biocontrol efficacy was evaluated through physiological and metabolic approaches against Fusarium oxysporum f.sp. lycopersici (FOL). The study elaborates on PBE-8's cell-free filtrate (CFF) antifungal activity through mycelial growth inhibition, metabolite profiling, and substrates utilization patterns. Additionally, under different CFF concentrations, reduction in spore count (94%-55%), biomass (50%), and cytoplasmic bulbous protrusions in mycelia were also observed. Furthermore, the effect of bacterial CFF on FOL metabolism was confirmed through GC-MS. CFF suppresses the concentration of aliphatic amino acids like L-valine, L-leucine, L-Isoleucine, glycine, and fatty acids such as linoleic acid and α- linolenic acid during the co-culturing conditions, which are essential for pathogenicity and resistance against host's systemic acquired resistance. The phenotype microarray assay revealed that CFF-treated FOL shows phenotype loss in 507 (56.58%) out of 896 substrates. Among 507, twenty-seven substrates showed significant phenotype loss, among which four substrates such as L-glutamic acid, L-glutamine, ammonia, and L-arginine are common in different crucial metabolic pathways of FOL, like alanine, aspartate, and glutamate metabolism, arginine and proline, carbon metabolism, arginine biosynthesis, nitrogen metabolism, amino-acyl tRNA synthesis, and biosynthesis of amino acids. The results suggest that PBE-8 CFF has certain antifungal metabolites that hinder the fungal metabolic pathways.


Assuntos
Fusarium , Lycopersicon esculentum , Alanina/genética , Alanina/farmacologia , Amônia , Antifúngicos/farmacologia , Arginina , Ácido Aspártico , Bacillus subtilis/genética , Biotransformação , Carbono , Fusarium/genética , Ácido Glutâmico/genética , Ácido Glutâmico/farmacologia , Glutamina/genética , Glutamina/farmacologia , Glicina , Isoleucina/genética , Isoleucina/farmacologia , Leucina/genética , Leucina/farmacologia , Ácidos Linoleicos/farmacologia , Ácidos Linolênicos/farmacologia , Lycopersicon esculentum/microbiologia , Análise em Microsséries , Nitrogênio , Fenótipo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Prolina/genética , Prolina/farmacologia , RNA de Transferência/farmacologia , Valina/genética , Valina/farmacologia
16.
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 , Lycopersicon esculentum , Microbiota , Bactérias/genética , Lycopersicon esculentum/microbiologia , Raízes de Plantas/microbiologia , Rizosfera , Solo , Microbiologia do Solo
17.
Radiat Prot Dosimetry ; 198(9-11): 720-725, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005952

RESUMO

Arbuscular mycorrhizal fungi (AMF) were inoculated into the root system of edible tomato plants to investigate their effect on the uptake and distribution of strontium radionuclide in the tissues of plants grown under laboratory conditions. The experiments were carried out in a sterile mixture of topsoil and sand, where in one series of experiments contaminated soil with 85Sr was used. Seeds were inoculated with a mixture of AMF at sowing, the second, control series was without application of AMF. Determination of radioactivity in soil and in different parts of tomato plants was carried out by gamma-spectrometric measurement. The obtained results and statistical analysis indicated a significant association between AMF inoculation of plants and the change in the distribution of 85Sr. The presence of AMF reduced the translocation of 85Sr from the root system to the aerial parts of tomato plants.


Assuntos
Lycopersicon esculentum , Micorrizas , Lycopersicon esculentum/microbiologia , Raízes de Plantas/microbiologia , Plantas , Solo/química , Radioisótopos de Estrôncio
18.
Int J Food Microbiol ; 379: 109861, 2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-35930961

RESUMO

Several bacterial and fungal diseases affect greenhouse-grown tomato crops, causing severe annual yield losses worldwide. The need to reduce chemical compound applications has encouraged the search of alternative approach for the control of tomato diseases, including the use of biological control agents. The presence of total and beneficial microbial populations was investigated on the surface and in the pulp of seven cultivars of tomato fruit coming from eleven greenhouses in the Pachino district (south-east of Sicily), recognized by the European Community with the "Protected Geographical Indication" label. Principal component analysis (PCA) showed that epiphytic and endophytic microbial populations clustered into groups according to the areas of origin. Approximately 240 tomato fruit-associated bacterial isolates were selected and a high percentage of them showed antagonistic activity against Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas euvesicatoria pv. perforans, Botrytis cinerea and Alternaria alternata. Analysis of the 16S rRNA gene sequences revealed a predominance of bacteria in Bacillus and Pseudomonas genera, followed by Citrobacter and Enterobacter. The presence of these genera differed according to the geographical areas of tomato samples, whereas their antagonistic capabilities varied according to the five tomato pathogens. The in vitro effectiveness of eight representative bacterial strains belonging to Pseudomonas, Bacillus and Enterobacter genera was confirmed in in vivo assays, carried out on tomato fruit artificially inoculated with A. alternata and B. cinerea. Altogether, these results revealed differences in population density of native microbiota of "Pomodoro di Pachino" fruits and allowed the selection of antagonistic bacterial strains that can be applied in field and in postharvest conditions as alternatives to chemical compounds.


Assuntos
Lycopersicon esculentum , Bactérias , Clavibacter , Frutas/microbiologia , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , RNA Ribossômico 16S/genética , Xanthomonas
19.
Int J Biol Macromol ; 220: 223-237, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970370

RESUMO

The present study evaluated the priming efficacy of chitosan and chitosan-derived nanoparticles (CNPs) against bacterial wilt of tomato. In the current study, seed-treated CNPs plus pathogen-inoculated tomato seedlings recorded significant protection of 62 % against pathogen-induced wilt disease and subsequently better growth. The induced resistance was witnessed by a prominent increase in lignin, callose and H2O2 deposition, followed by superoxide radical accumulation in leaves. Additionally, chitosan and CNPs-treated tomato plants recorded a remarkable increase in the upregulation of phenylalanine ammonia-lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO), catalase (CAT) and ß-1, 3 glucanase (GLU) in comparison with untreated plants. The chitosan and CNPs-induced antioxidant enzymes were positively correlated with the stimulation of corresponding gene expression in CNPs treated plants related to pathogen-inoculated ones. The results of this study describe that how the application of chitosan and CNPs elicit defense responses at the cellular, biochemical and gene expression in tomato plants against bacterial wilt disease, thereby improve growth and yield.


Assuntos
Quitosana , Lycopersicon esculentum , Nanopartículas , Antioxidantes/metabolismo , Catalase/genética , Catalase/metabolismo , Catecol Oxidase/metabolismo , Quitosana/metabolismo , Quitosana/farmacologia , Peróxido de Hidrogênio/metabolismo , Imunidade , Lignina/metabolismo , Lycopersicon esculentum/microbiologia , Fenilalanina Amônia-Liase/metabolismo , Doenças das Plantas/microbiologia , Superóxidos/metabolismo
20.
BMC Microbiol ; 22(1): 210, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045321

RESUMO

BACKGROUND: To explore and utilize abundant soil microbes and their beneficial functions, the bacterial and fungal compositions in rhizospheres between red- and yellow-fruited tomato varieties were analyzed using high-throughput sequencing technique. RESULT: Our results indicated that different soil microbes in rhizospheres of tomatoes were exactly recruited by different color fruit tomatoes. For the reasons as not only soil bacterial community, but also soil fungal compositions were all different between red and yellow fruit tomatoes. For example, Nocardioides, norank_f_norank_o_Vicinamibacterales, norank_f_norank_o_norank_c_KD4-96, norank_f_Birii41, norank_f_norank_o_S085 and Bradyrhizobium were the specific dominant soil bacterial genera, and Lecythophora, Derxomyces and unclassified_f_Pyronemataceae were the dominant soil fungal genera in the rhizospheres of red tomato varieties. By contrast, unclassified_f__Micromonsporaceae, Acidipila, Roseisolibacter, Gaiella and norank_f_Xanthobacteraceae were the unique dominant soil bacterial genera in the rhizospheres of yellow tomato varieties. And unclassified_o__Onygenales, Trichocladium, unclassified_c__Sordariomycetes, Pseudogymnoascus, Acremonium, Oidiodendron, Phialemonium, Penicillium, Phialosimplex were the unique dominant soil fungal genera in rhizospheres of yellow tomato varieties. Moreover, a higher abundance of specific soil bacterial and fungal genera in the rhizosphere was found in rhizospheres of the yellow than those of the red tomato varieties. CONCLUSION: Soil bacterial and fungal compositions in rhizospheres between red- and yellow-fruited tomato varieties were found significantly different which growing in the same environment under the identical managements. It suggested that different soil microbes in rhizospheres exactly were recruited by different phenotypes tomato varieties related to fruit color formation.


Assuntos
Lycopersicon esculentum , Rizosfera , Bactérias/genética , Frutas , Lycopersicon esculentum/microbiologia , Fenótipo , Solo , Microbiologia do Solo
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