Co-infection, caused by multiple pathogen attacks on an organism, can lead to disease development or immunity. This complex interaction can be synergetic, co-existing, or antagonistic, ultimately influencing disease severity. The interaction between fungus, bacterium, and virus (three kingdom pathogens) is most prevalent. However, the underlying mechanisms of co-infection need to be explored further. In this study, we investigated the co-infection phenomenon in rice plants exposed to multiple pathogen species, specifically Rice necrosis mosaic virus (RNMV) and rice blast fungus (Magnaporthe oryzae, MO), bacterial leaf blight (Xanthomonas oryzae pv. oryzae, XO) or Cucumber mosaic virus (CMV). Our research showed that RNMV interacts synergistically with MO, XO, or CMV, increasing pathogen growth and lesion size. These findings suggest positive synergy in RNMV co-infections with three kingdom pathogens, increasing accumulation and symptoms. Additionally, to investigate the role of RNAi in pathogen synergism, we analyzed rice mutant lines deficient in RNA-dependent RNA polymerase 1 (OsRDR1) or 6 (OsRDR6). Notably, we observed the loss of synergy in each mutant line, highlighting the crucial role of OsRDR1 and OsRDR6 in maintaining the positive interaction between RNMV and three kingdom pathogens. Hence, our study emphasized the role of the RNA silencing pathway in the intricate landscape of pathogen interactions; the study's outcome could be applied to understand the plant defense response to improve crop yields.
- Klíčová slova
- Cucumber mosaic virus, Magnaporthe oryzae, RNA dependent RNA polymerase 1/6, Rice necrosis mosaic virus, Synergy, Xanthomonas oryzae pv. oryzae,
- MeSH
- Ascomycota MeSH
- Cucumovirus fyziologie MeSH
- interakce hostitele a patogenu MeSH
- koinfekce virologie mikrobiologie MeSH
- Magnaporthe fyziologie MeSH
- mutace MeSH
- nemoci rostlin * mikrobiologie virologie MeSH
- rostlinné proteiny genetika metabolismus MeSH
- rýže (rod) * mikrobiologie virologie genetika MeSH
- Xanthomonas * fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- rostlinné proteiny MeSH
The study aimed to assess the potential of phyllospheric bacterial strains isolated from cauliflower plants as biocontrol agents against black rot disease caused by Xanthomonas campestris pv. campestris, through both in vitro and in vivo evaluations. A total of 46 bacterial strains were isolated from healthy and infected cauliflower leaves of both resistant and susceptible plants, and evaluated them for various traits, including plant growth-promoting activities and in vitro antagonistic activity against Xanthomonas campestris pv. campestris. Further, a pot experiment was conducted with the susceptible cauliflower genotype (Pusa Sharad) and 10 selected phyllospheric bacterial isolates to assess their biocontrol efficacy against the disease. The results showed that 82.60% of phyllospheric bacterial isolates were positive for phosphate solubilization, 63.04% for ammonia production, 58.69% for HCN production, 36.95% for siderophore production, and 78.26% had the capacity to produce IAA. Out of the 46 isolates, 23 exhibited in vitro antagonistic activity against X. campestris pv. campestris and 10 isolates were selected for a pot experiment under glasshouse conditions based on their good plant growth-promoting activities and antagonistic assay. The results revealed that bacterial isolate CFLB-27 exhibited the highest biocontrol efficiency (65.41%), followed by CFLB-24 (58.30%), CFLB-31 (47.11%), and CFLB-26 (46.03%). These four isolates were identified as Pseudomonas fluorescens CFLB-27, Bacillus velezensis CFLB-24, Bacillus amyloliquefaciens CFLB-31, and Stenotrophomonas rhizophila CFLB-26. This study provides valuable insights into the potential of phyllospheric bacteria as an effective tool for disease management in sustainable agriculture.
- Klíčová slova
- Pseudomonas fluorescens CFLB-27, Xanthomonas campestris pv. campestris, Biocontrol efficiency, Black rot, Phyllospheric bacterial isolates,
- MeSH
- antibióza * MeSH
- Bacteria klasifikace izolace a purifikace genetika růst a vývoj MeSH
- biologická ochrana MeSH
- Brassica * mikrobiologie MeSH
- listy rostlin * mikrobiologie MeSH
- nemoci rostlin * mikrobiologie prevence a kontrola MeSH
- Xanthomonas campestris * genetika růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biologická ochrana MeSH
The newly discovered Xanthomonas phage M29 (Xp M29) is the first lytic phage infecting Xanthomonas campestris pv. campestris (Xcc) that was isolated from cabbage leaves in the Czech Republic. The phage consists of icosahedral head approximately 60 nm in diameter and a probably contractile tail of 170 nm. The complete genome size was 42 891 bp, with a G + C content of 59.6%, and 69 ORFs were predicted on both strands. Pairwise nucleotide comparison showed the highest similarity with the recently described Xanthomonas phage FoX3 (91.2%). Bacteriophage Xp M29 has a narrow host range infecting 5 out of 21 isolates of Xcc. Xp M29 is a novel species in a newly formed genus Foxunavirus assigned directly to the class Caudoviricetes.
- Klíčová slova
- Bacteriophage, Biocontrol, Xanthomonas campestris pv. campestris whole-genome sequence,
- MeSH
- bakteriofágy * genetika MeSH
- Myoviridae MeSH
- Xanthomonas campestris * genetika MeSH
- Xanthomonas * genetika MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Employing aerobic fermentation, Gram-negative bacteria belonging to the genus Xanthomonas produce the high molecular weight natural heteropolysaccharide known as xanthan. It has various amounts of O-acetyl and pyruvyl residues together with D-glucosyl, D-mannosyl, and D-glucuronyl acid residues in a molar ratio of 2:2:1. The unique structure of xanthan allowed its various applications in a wide range of industries such as the food industry, pharmacology, cosmetics and enhanced oil recovery primarily in petroleum. The cultivation medium used in the manufacture of this biopolymer is critical. Many attempts have been undertaken to generate xanthan gum from agro-based and food industry wastes since producing xanthan gum from synthetic media is expensive. Optimal composition and processing parameters must also be considered to achieve an economically viable manufacturing process. There have been several attempts to adjust the nutrient content and feeding method, temperature, pH, agitation and the use of antifoam in xanthan fermentations. Various modifications in technological approaches have been applied to enhance its physicochemical properties which showed significant improvement in the area studied. This review describes the biosynthesis production of xanthan with an emphasis on the importance of the upstream processes involving medium, processing parameters, and other factors that significantly contributed to the final application of this precious polysaccharide.
- Klíčová slova
- Biosynthesis, Production, Xanthan, Xanthan applications, Xanthomonas sp,
- MeSH
- bakteriální polysacharidy MeSH
- fermentace MeSH
- Xanthomonas campestris * metabolismus MeSH
- Xanthomonas * MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- bakteriální polysacharidy MeSH
- xanthan gum MeSH Prohlížeč
Xanthomonas euvesicatoria and X. vesicatoria are two economically important causal agents of bacterial spot (BS) of tomato and pepper. Management of BS in the field requires rapid and accurate detection. Therefore, this work aimed to develop a pipeline to design a simple, fast, and reliable assay for the detection of X. euvesicatoria and X. vesicatoria by loop-mediated isothermal amplification. In total, 109 publicly available whole genomic sequences of 24 different species of bacterial pathogens were used to design primers that would amplify the DNA of the two target species. Laboratory testing of the assay was performed on pure bacterial cultures and artificially infected plants, and amplification was conducted with both a sophisticated laboratory instrument and a simple mobile platform. The testing of the assay confirmed its specificity with a sensitivity reaching 1 pg µl-1 for both pathogens with an assay duration of 40 min on a mobile detection platform. Our diagnostics development pipeline enables the easy and fast design of a reliable detection assay in the genomics age. By validating the pipeline with X. euvesicatoria and X. vesicatoria pathogens, we have simultaneously developed an assay with high specificity, sensitivity, and speed, which will allow it to be deployed, contributing to successful management of BS.
- Klíčová slova
- LAMP, LAMP pipeline, Xanthomonas euvesicatoria, Xanthomonas vesicatoria, bacterial spot of tomato and pepper, diagnostic assay, diagnostics pipeline,
- MeSH
- diagnostické techniky molekulární MeSH
- Solanum lycopersicum * MeSH
- techniky amplifikace nukleových kyselin MeSH
- Xanthomonas * genetika MeSH
- Publikační typ
- časopisecké články MeSH
Climatic conditions play a significant role in the development of citrus canker caused by Xanthomonas citri pv. citri (Xcc). Citrus canker is regarded as one of the major threats being faced by citrus industry in citrus growing countries of the world. Climatic factors exert significant impacts on growth stage, host susceptibility, succulence, vigor, survival, multiplication rate, pathogen dispersion, spore penetration rate, and spore germination. Predicting the impacts of climatic factors on these traits could aid in the development of effective management strategies against the disease. This study predicted the impacts of environmental variables, i.e., temperature, relative humidity, rainfall, and wind speed the development of citrus canker through multiple regression. These environmental variables were correlated with the development of canker on thirty (30) citrus varieties during 2017 to 2020. Significant positive correlations were noted among environment variables and disease development modeled through multiple regression model (Y = +24.02 + 0.5585 X1 + 0.2997 X2 + 0.3534 X3 + 3.590 X4 + 1.639 X5). Goodness of fit of the model was signified by coefficient determination value (97.5%). Results revealed the optimum values of environmental variables, i.e., maximum temperature (37°C), minimum temperature (27°C), relative humidity (55%), rainfall (4.7-7.1 mm) and wind speed (8 Km/h), which were conducive for the development of citrus canker. Current study would help researchers in designing better management strategies against citrus canker disease under changing climatic conditions in the future.
Epigenetics is the study of heritable alterations in phenotypes that are not caused by changes in DNA sequence. In the present study, we characterized the genetic and phenotypic alterations of the bacterial plant pathogen Xanthomonas campestris pv. campestris (Xcc) under different treatments with several epigenetic modulating chemicals. The use of DNA demethylating chemicals unambiguously caused a durable decrease in Xcc bacterial virulence, even after its reisolation from infected plants. The first-time use of chemicals to modify the activity of sirtuins also showed some noticeable results in terms of increasing bacterial virulence, but this effect was not typically stable. Changes in treated strains were also confirmed by using methylation sensitive amplification (MSAP), but with respect to registered SNPs induction, it was necessary to consider their contribution to the observed polymorphism. The molecular basis of the altered virulence was deciphered by using dualRNA-seq analysis of treated Xcc strains infecting Brassica rapa plants. The results of the present study should promote more intensive research in the generally understudied field of bacterial epigenetics, where artificially induced modification by epigenetic modulating chemicals can significantly increase the diversity of bacterial properties and potentially contribute to the further development of the fields, such as bacterial ecology and adaptation.
- Klíčová slova
- DNA methylation, Xanthomonas campestris, bacterial epigenetics, dual RNA-seq, virulence,
- MeSH
- bakteriální proteiny genetika metabolismus MeSH
- Brassica rapa mikrobiologie MeSH
- epigeneze genetická účinky léků MeSH
- inhibitory enzymů farmakologie MeSH
- jednonukleotidový polymorfismus MeSH
- metylace DNA MeSH
- puriny farmakologie MeSH
- sirtuiny antagonisté a inhibitory genetika metabolismus MeSH
- virulence genetika MeSH
- Xanthomonas campestris účinky léků genetika patogenita MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bakteriální proteiny MeSH
- inhibitory enzymů MeSH
- lomeguatrib MeSH Prohlížeč
- puriny MeSH
- sirtuiny MeSH
Bacterial spot, caused by a group of Xanthomonads (Xanthomonas spp.), is a devastating disease. It can adversely affect the Capsicum annum productivity. Scientists are working on the role of antioxidants to meet this challenge. However, research is lacking on the role of antioxidant enzymes and their isoforms in the non-compatible pathogen and host plant interaction and resistance mechanisms in capsicum varieties. The present study was conducted to ascertain the defensive role of antioxidant enzymes and their isoforms in chilli varieties Hybrid, Desi, Serrano, Padron, and Shehzadi against bacterial spot disease-induced Xanthomonas sp. The seedlings were inoculated with bacterial pathogen @ 107 CFU/mL, and samples were harvested after regular intervals of 24 h for 4 days followed by inoculation. Total plant proteins were extracted in phosphate buffer and quantified through Bradford assay. The crude protein extracts were analyzed through quantitative enzymatic assays in order to document activity levels of various antioxidant enzymes, including peroxidase (POD), Catalase (CAT), Ascorbate peroxidase (APX), and Superoxide dismutase (SOD). Moreover, the profiles appearance of these enzymes and their isoforms were determined using native polyacrylamide gel electrophoresis (PAGE) analysis. These enzymes exhibited maximum activity in Hybrid (HiR) cultivar followed by Desi (R), Serrano (S), Padron, and Shehzadi (HS). Both the number of isoforms and expression levels were higher in highly resistant cultivars compared to susceptible and highly susceptible cultivars. The induction of POD, CAT, and SOD occurs at the early stages of growth in resistant Capsicum cultivars. At the same time, APX seems to make the second line of antioxidant defense mechanisms. We found that modulating antioxidant enzymes and isoforms activity at the seedling stage was an important mechanism for mitigating plant growth inhibition in the resistant ones.
- MeSH
- antioxidancia metabolismus MeSH
- askorbátperoxidasa metabolismus MeSH
- Capsicum růst a vývoj mikrobiologie MeSH
- fyziologický stres fyziologie MeSH
- katalasa metabolismus MeSH
- nemoci rostlin mikrobiologie MeSH
- oxidační stres fyziologie MeSH
- peroxid vodíku analýza MeSH
- peroxidasa metabolismus MeSH
- protein - isoformy metabolismus MeSH
- rostlinné proteiny analýza MeSH
- superoxiddismutasa metabolismus MeSH
- Xanthomonas patogenita MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- antioxidancia MeSH
- askorbátperoxidasa MeSH
- katalasa MeSH
- peroxid vodíku MeSH
- peroxidasa MeSH
- protein - isoformy MeSH
- rostlinné proteiny MeSH
- superoxiddismutasa MeSH
A multiplex real-time PCR method based on fluorescent TaqMan® probes was developed for the simultaneous detection of the tomato pathogenic bacteria Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato and bacterial spot-causing xanthomonads. The specificity of the multiplex assay was validated on 44 bacterial strains, including 32 target pathogen strains as well as closely related species and nontarget tomato pathogenic bacteria. The designed multiplex real-time PCR showed high sensitivity when positive amplification was observed for one pg of bacterial DNA in the cases of Clavibacter michiganensis subsp. michiganensis and Pseudomonas syringae pv. tomato bacteria and 100 pg for bacterial spot-causing xanthomonads. The reliability of the developed multiplex real-time PCR assay for in planta detection was verified by recognition of the target pathogens in 18 tomato plants artificially inoculated by each of the target bacteria and tomato samples from production greenhouses.
- MeSH
- Actinobacteria genetika izolace a purifikace fyziologie MeSH
- Clavibacter MeSH
- kvantitativní polymerázová řetězová reakce * MeSH
- prostředí kontrolované MeSH
- Pseudomonas syringae genetika izolace a purifikace fyziologie MeSH
- Solanum lycopersicum růst a vývoj mikrobiologie MeSH
- Xanthomonas genetika izolace a purifikace fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Citrus canker, caused by Xanthomonas axonopodis pv. citri ('Xac'), is an important quarantine disease in citrus crops. Arbuscular mycorrhizal fungi (AMF) form symbiotic interactions with host plants and further affect their disease resistance, possibly by modulating the activity of salicylic acid (SA), a key phytohormone in disease resistance. Common mycorrhizal networks (CMNs) can interconnect plants, but it is not yet clear whether CMNs promote resistance to citrus canker and, if so, whether SA signaling is involved in this process. To test this possibility, we used a two-chambered rootbox to establish CMNs between trifoliate orange (Poncirus trifoliata) seedlings in chambers inoculated (treated) or not (neighboring) with the AMF, Paraglomus occultum. A subset of the AMF-inoculated seedlings were also inoculated with Xac (+AMF+Xac). At 2 d post-inoculation (dpi), compared with the +AMF-Xac treatment, neighboring seedlings in +AMF+Xac treatment had lower expression levels of the SA biosynthetic genes, PtPAL, PtEPS1, and PtPBS3, but higher SA levels, which attributed to the upregulation of PtPAL and PtPBS3 in treated seedlings and the transfer of SA, via CMNs, to the neighboring seedlings. At 4 dpi, the pathogenesis-related (PR) protein genes, PtPR1, PtPR4, and PtPR5, and the transcriptional regulatory factor gene, PtNPR1, were activated in neighboring seedlings of +AMF+Xac treatment. At 9 dpi, root phenylalanine ammonia-lyase activity and total soluble phenol and lignin concentrations increased in neighboring seedlings of +AMF+Xac treatment, likely due to the linkage and signal transfer, via CMNs. These findings support the hypothesis that CMNs transfer the SA signal from infected to neighboring healthy seedlings, to activate defense responses and affording protection to neighboring plants against citrus canker infection.
- MeSH
- kyselina salicylová metabolismus MeSH
- Poncirus metabolismus mikrobiologie MeSH
- Xanthomonas axonopodis patogenita MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- kyselina salicylová MeSH
