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Volatile organic compounds (VOCs) play an important role in the communication among organisms, including plants, beneficial or pathogenic microbes, and pests. In vitro, we observed that the growth of seven out of eight Basidiomycete species tested was inhibited by the VOCs of the biocontrol agent Pseudomonas protegens strain CHA0. In the Ascomycota phylum, only some species were sensitive (e.g., Sclerotinia sclerotiorum, Botrytis cinerea, etc.) but others were resistant (e.g., Fusarium oxysporum f. sp. cubense, Verticillium dahliae, etc.). We further discovered that CHA0 as well as other ten beneficial or phytopathogenic bacterial strains were all able to inhibit Heterobasidion abietinum, which was used in this research as a model species. Moreover, such an inhibition occurred only when bacteria grew on media containing digested proteins like peptone or tryptone (e.g., Luria-Bertani agar or LBA). Also, the inhibition co-occurred with a pH increase of the agar medium where the fungus grew. Therefore, biogenic ammonia originating from protein degradation by bacteria was hypothesized to play a major role in fungus inhibition. Indeed, when tested as a synthetic compound, it was highly toxic to H. abietinum (effective concentration 50% or EC50 = 1.18 M; minimum inhibitory concentration or MIC = 2.14 M). Using gas chromatography coupled to mass spectrometry (GC/MS), eight VOCs were found specifically emitted by CHA0 grown on LBA compared to the bacterium grown on potato dextrose agar (PDA). Among them, two compounds were even more toxic than ammonia against H. abietinum: dimethyl trisulfide had EC50 = 0.02 M and MIC = 0.2 M, and 2-ethylhexanol had EC50 = 0.33 M and MIC = 0.77 M. The fungus growth inhibition was the result of severe cellular and sub-cellular alterations of hyphae occurring as early as 15 min of exposure to VOCs, as evidenced by transmission and scanning electron microscopy observations. Transcriptome reprogramming of H. abietinum induced by CHA0’s VOCs pointed out that detrimental effects occurred on ribosomes and protein synthesis while the cells tried to react by activating defense mechanisms, which required a lot of energy diverted from the growth and development (fitness cost).
Maria Isabella Prigigallo; Angelo De Stradis; Abhishek Anand; Francesco Mannerucci; Floriane L’Haridon; Laure Weisskopf; Giovanni Bubici. Basidiomycetes Are Particularly Sensitive to Bacterial Volatile Compounds: Mechanistic Insight Into the Case Study of Pseudomonas protegens Volatilome Against Heterobasidion abietinum. Frontiers in Microbiology 2021, 12, 1 .
AMA StyleMaria Isabella Prigigallo, Angelo De Stradis, Abhishek Anand, Francesco Mannerucci, Floriane L’Haridon, Laure Weisskopf, Giovanni Bubici. Basidiomycetes Are Particularly Sensitive to Bacterial Volatile Compounds: Mechanistic Insight Into the Case Study of Pseudomonas protegens Volatilome Against Heterobasidion abietinum. Frontiers in Microbiology. 2021; 12 ():1.
Chicago/Turabian StyleMaria Isabella Prigigallo; Angelo De Stradis; Abhishek Anand; Francesco Mannerucci; Floriane L’Haridon; Laure Weisskopf; Giovanni Bubici. 2021. "Basidiomycetes Are Particularly Sensitive to Bacterial Volatile Compounds: Mechanistic Insight Into the Case Study of Pseudomonas protegens Volatilome Against Heterobasidion abietinum." Frontiers in Microbiology 12, no. : 1.
A study was carried out on the effect of the root endophytic fungus Pochonia chlamydosporia on plant systemic signal of defense related genes during fungal or nematode parasitism. Different biotic stress factors were examined, inoculating roots of dicot and monocot hosts with the endophyte, and measuring the expression of defense genes in leaves. A first greenhouse assay was carried out on expression of PAL, PIN II, PR1 and LOX D in leaves of tomato cv Tondino inoculated with Phytophthora infestans (CBS 120920), inoculating or not the roots of infected plants with P. chlamydosporia DSM 26985. In a second assay, plants of banana (Musa acuminata cv Grand Naine) were artificially infected with Fusarium oxysporum f. sp. cubense Tropical race 4 (TR4) and inoculated or not with DSM 26985. In a further experiment, banana plants were inoculated or not with P. chlamydosporia plus juveniles of the root knot nematode (RKN) Meloidogyne incognita. A similar assay was also carried out in vitro with adults and juveniles of the lesion nematode Pratylenchus goodeyi. Differential expression of the defense genes examined was observed for all plant-stress associations, indicative of early, upward systemic signals induced by the endophyte. Changes in expression profiles included a 5-fold down-regulation of PIN II at 2 dai in leaves of tomato plants treated with P. infestans and/or P. chlamydosporia, and the up-regulation of PAL by the endophyte alone, at 2 and 7 dai. In the TR4 assay, PR1 was significantly up-regulated at 7 dai in banana leaves, but only in the P. chlamydosporia treated plants. At 10 dai, PIN II expression was significantly higher in leaves of plants inoculated only with TR4. The banana-RKN assay showed a PR1 expression significantly higher than controls at 4 and 7 dai in plants inoculated with P. chlamydosporia alone, and a down-regulation at 4 dai in leaves of plants also inoculated with RKN, with a PR1 differential up-regulation at 10 dai. Pratylenchus goodeyi down-regulated PIN at 21 dai, with or without the endophyte, as well as PAL but only in presence of P. chlamydosporia. When inoculated alone, the endophyte up-regulated PR1 and LOX. The gene expression patterns observed in leaves suggest specific and time-dependent relationships linking host plants and P. chlamydosporia in presence of biotic stress factors, functional to a systemic, although complex, activation of defense genes.
Shimaa Tolba; Laura Rosso; Isabella Pentimone; Mariantonietta Colagiero; Mahmoud Moustafa; Ibrahim Elshawaf; Giovanni Bubici; Maria Prigigallo; Aurelio Ciancio. Root Endophytism by Pochonia chlamydosporia Affects Defense-Gene Expression in Leaves of Monocot and Dicot Hosts under Multiple Biotic Interactions. Plants 2021, 10, 718 .
AMA StyleShimaa Tolba, Laura Rosso, Isabella Pentimone, Mariantonietta Colagiero, Mahmoud Moustafa, Ibrahim Elshawaf, Giovanni Bubici, Maria Prigigallo, Aurelio Ciancio. Root Endophytism by Pochonia chlamydosporia Affects Defense-Gene Expression in Leaves of Monocot and Dicot Hosts under Multiple Biotic Interactions. Plants. 2021; 10 (4):718.
Chicago/Turabian StyleShimaa Tolba; Laura Rosso; Isabella Pentimone; Mariantonietta Colagiero; Mahmoud Moustafa; Ibrahim Elshawaf; Giovanni Bubici; Maria Prigigallo; Aurelio Ciancio. 2021. "Root Endophytism by Pochonia chlamydosporia Affects Defense-Gene Expression in Leaves of Monocot and Dicot Hosts under Multiple Biotic Interactions." Plants 10, no. 4: 718.
We report the first occurrence of the orange spiny whitefly (Aleurocanthus spiniferus; OSW) on the tree of heaven (Ailanthus altissima) in Bari, Apulia region, Italy. After our first observation in 2016, the infestation recurred regularly during the following years and expanded to the neighboring trees. Since then, we have also found the insect on numerous patches of the tree of heaven and other plant species in the Bari province. Nevertheless, the tree of heaven was not particularly threatened by the insect, so that a possible contribution by OSW for the control of such an invasive plant cannot be hypothesized hitherto. This work was also aimed at profiling the microbiome of OSW feeding on A. altissima. For this purpose, we used the denaturing gradient gel electrophoresis (DGGE) and the deep sequencing of small RNAs (sRNAs). Both techniques unveiled the presence of “Candidatus Portiera” (primary endosymbiont), Wolbachia sp. and Rickettsia sp., endosymbionts already reported for other Aleyrodidae. Deep sequencing data were analyzed by four computational pipelines in order to understand the reliability of the detection of fungi, bacteria, and viruses: Kraken, Kaiju, Velvet, and VelvetOptimiser. Some contigs assembled by Velvet or VelvetOptimiser were associated with insects, but not necessarily in the Aleurocanthus genus or Aleyrodidae family, suggesting the non-specificity of sRNAs or possible traces of parasitoids in the sample (e.g., Eretmocerus sp.). Finally, deep sequencing data were used to describe the microtranscriptome of OSW: 56 canonical and at least four high-confidence novel microRNAs (miRNAs) were identified. The overall miRNA abundance in OSW was in agreement with previous works on Bemisia tabaci, and bantam-3p, miR-276a-3p, miR-317-3p, miR-750-3p, and mir-8-3p were the most represented miRNAs.
Giovanni Bubici; Maria Isabella Prigigallo; Francesca Garganese; Francesco Nugnes; Maurice Jansen; Francesco Porcelli. First Report of Aleurocanthus spiniferus on Ailanthus altissima: Profiling of the Insect Microbiome and MicroRNAs. Insects 2020, 11, 161 .
AMA StyleGiovanni Bubici, Maria Isabella Prigigallo, Francesca Garganese, Francesco Nugnes, Maurice Jansen, Francesco Porcelli. First Report of Aleurocanthus spiniferus on Ailanthus altissima: Profiling of the Insect Microbiome and MicroRNAs. Insects. 2020; 11 (3):161.
Chicago/Turabian StyleGiovanni Bubici; Maria Isabella Prigigallo; Francesca Garganese; Francesco Nugnes; Maurice Jansen; Francesco Porcelli. 2020. "First Report of Aleurocanthus spiniferus on Ailanthus altissima: Profiling of the Insect Microbiome and MicroRNAs." Insects 11, no. 3: 161.
Potato virus Y (PVY) isolate PVYC-to induces growth reduction and foliar symptoms in tomato, but new vegetation displays symptom recovery at a later stage. In order to investigate the role of micro(mi)RNA and secondary small(s)RNA-regulated mechanisms in tomato defenses against PVY, we performed sRNA sequencing from healthy and PVYC-to infected tomato plants at 21 and 30 days post-inoculation (dpi). A total of 792 miRNA sequences were obtained, among which were 123 canonical miRNA sequences, many isomiR variants, and 30 novel miRNAs. MiRNAs were mostly overexpressed in infected vs. healthy plants, whereas only a few miRNAs were underexpressed. Increased accumulation of isomiRs was correlated with viral infection. Among miRNA targets, enriched functional categories included resistance (R) gene families, transcription and hormone factors, and RNA silencing genes. Several 22-nt miRNAs were shown to target R genes and trigger the production of 21-nt phased sRNAs (phasiRNAs). Next, 500 phasiRNA-generating loci were identified, and were shown to be mostly active in PVY-infected tissues and at 21 dpi. These data demonstrate that sRNA-regulated host responses, encompassing miRNA alteration, diversification within miRNA families, and phasiRNA accumulation, regulate R and disease-responsive genes. The dynamic regulation of miRNAs and secondary sRNAs over time suggests a functional role of sRNA-mediated defenses in the recovery phenotype.
Maria I. Prigigallo; Maja Križnik; Domenico De Paola; Domenico Catalano; Kristina Gruden; Mariella M. Finetti-Sialer; Fabrizio Cillo. Potato Virus Y Infection Alters Small RNA Metabolism and Immune Response in Tomato. Viruses 2019, 11, 1100 .
AMA StyleMaria I. Prigigallo, Maja Križnik, Domenico De Paola, Domenico Catalano, Kristina Gruden, Mariella M. Finetti-Sialer, Fabrizio Cillo. Potato Virus Y Infection Alters Small RNA Metabolism and Immune Response in Tomato. Viruses. 2019; 11 (12):1100.
Chicago/Turabian StyleMaria I. Prigigallo; Maja Križnik; Domenico De Paola; Domenico Catalano; Kristina Gruden; Mariella M. Finetti-Sialer; Fabrizio Cillo. 2019. "Potato Virus Y Infection Alters Small RNA Metabolism and Immune Response in Tomato." Viruses 11, no. 12: 1100.
Plants defend themselves from pathogenic virus infections by deploying a complex defense system. Fundamental in the plant antiviral immune system is the RNA silencing (RS) pathway, which consists in a multilayered set of enzymatic components. The RS machinery targets the double-stranded RNA, generating 21–24 nucleotides (nt) small interfering RNAs (siRNAs) that guide the cleavage of viral RNA in a sequence-specific manner. RS signals are then amplified and transmitted cell-to-cell and systemically, in a process that is provided with self-regulatory feedback mechanisms. All the steps of the RS pathway were revealed to be targeted by viral counterattack strategies that allow pathogens to escape host defenses and establish a successful infection. Viral suppressors of RNA silencing (VSRs) are virus-encoded proteins that interfere with RS by blocking or destabilizing the host antiviral functions. This chapter reviews the current knowledge on VSRs mechanisms of action, and describes the latest discoveries in this fascinating evolutionary arms race between plants and viruses.
Livia Stavolone; Maria Isabella Prigigallo; Fabrizio Cillo. Plant viruses against RNA silencing-based defenses: Strategies and solutions. Applied Plant Biotechnology for Improving Resistance to Biotic Stress 2019, 225 -250.
AMA StyleLivia Stavolone, Maria Isabella Prigigallo, Fabrizio Cillo. Plant viruses against RNA silencing-based defenses: Strategies and solutions. Applied Plant Biotechnology for Improving Resistance to Biotic Stress. 2019; ():225-250.
Chicago/Turabian StyleLivia Stavolone; Maria Isabella Prigigallo; Fabrizio Cillo. 2019. "Plant viruses against RNA silencing-based defenses: Strategies and solutions." Applied Plant Biotechnology for Improving Resistance to Biotic Stress , no. : 225-250.
A Corrigendum onBiological Control Agents Against Fusarium Wilt of Banana by Bubici, G., Kaushal, M., Prigigallo, M. I., Gómez-Lama Cabanás, C., and Mercado-Blanco, J. (2019). Front. Microbiol. 10:616. doi: 10.3389/fmicb.2019.00616 In the original article, the reference for “Kalaiponmani et al., 2017” was incorrectly written as “Gopalakrishnan, V. (2017). Optimization of protein isolation and preliminary comparative proteomics of pathogenic Fusarium oxysporum f. sp. cubense (p-Foc) and non-pathogenic Fusarium oxysporum (np-Fo). J. Plant Pathol. 99, 361–369. 10.4454/jpp.v99i2.3883” It should be “Kalaiponmani, K., Thangavelu R., and Varun, G. (2017). Optimization of protein isolation and preliminary comparative proteomics of pathogenic Fusarium oxysporum f. sp. cubense (p-Foc) and non-pathogenic Fusarium oxysporum (np-Fo). J. Plant Pathol. 99, 361–369. 10.4454/jpp.v99i2.3883” The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. Keywords: Musa acuminata, Fusarium oxysporum f. sp. cubense, Panama disease, soil microbiota, beneficial microorganisms, biocontrol Citation: Bubici G, Kaushal M, Prigigallo MI, Gómez-Lama Cabanás C and Mercado-Blanco J (2019) Corrigendum: Biological Control Agents Against Fusarium Wilt of Banana. Front. Microbiol. 10:1290. doi: 10.3389/fmicb.2019.01290 Received: 02 May 2019; Accepted: 23 May 2019;Published: 11 June 2019. Approved by: Copyright © 2019 Bubici, Kaushal, Prigigallo, Gómez-Lama Cabanás and Mercado-Blanco. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Giovanni Bubici, [email protected]
Giovanni Bubici; Manoj Kaushal; Maria Isabella Prigigallo; Carmen Gómez-Lama Cabanás; Jesús Mercado-Blanco. Corrigendum: Biological Control Agents Against Fusarium Wilt of Banana. Frontiers in Microbiology 2019, 10, 1290 .
AMA StyleGiovanni Bubici, Manoj Kaushal, Maria Isabella Prigigallo, Carmen Gómez-Lama Cabanás, Jesús Mercado-Blanco. Corrigendum: Biological Control Agents Against Fusarium Wilt of Banana. Frontiers in Microbiology. 2019; 10 ():1290.
Chicago/Turabian StyleGiovanni Bubici; Manoj Kaushal; Maria Isabella Prigigallo; Carmen Gómez-Lama Cabanás; Jesús Mercado-Blanco. 2019. "Corrigendum: Biological Control Agents Against Fusarium Wilt of Banana." Frontiers in Microbiology 10, no. : 1290.
Chayote (Sechium edule, fam. Cucurbitaceae) is not reported as a host of Verticillium dahliae. In an olive orchard intercropped with horticultural crops and infested by Verticillium dahliae, chayote did not show Verticillium wilt symptoms over three years (2015–2017). Hence, we hypothesized that chayote is not a V. dahliae host. Using a V. dahliae isolate obtained from a wilted eggplant located in that field, we carried out a pathogenicity test on two chayote varieties, one with spiny fruits and another with non-spiny fruits (10 plants each). Eggplant, tomato and ‘Carosello’ ecotype (Cucumis melo), all susceptible to the disease, were included as positive controls. After four months in the greenhouse, chayote plants did not show Verticillium wilt symptoms, which occurred in the control plants since 4–6 weeks after planting. From chayote roots, isolation on PDA did not yield colonies of V. dahliae, but PCR assays from some plants were positive. This indicated very limited colonization of roots by V. dahliae, which is known to occur even in resistant or symptomless responses. In conclusion, we demonstrate the symptomless response of chayote to V. dahliae, while assessment of the non-host response needs further pathogenicity test with V. dahliae isolates from diverse plant species.
Giovanni Bubici; Maria Isabella Prigigallo; Valentino Poliseno. Symptomless reaction of Sechium edule (Jacq.) Sw. to Verticillium dahliae Kleb. Journal of Plant Pathology 2019, 101, 1195 -1197.
AMA StyleGiovanni Bubici, Maria Isabella Prigigallo, Valentino Poliseno. Symptomless reaction of Sechium edule (Jacq.) Sw. to Verticillium dahliae Kleb. Journal of Plant Pathology. 2019; 101 (4):1195-1197.
Chicago/Turabian StyleGiovanni Bubici; Maria Isabella Prigigallo; Valentino Poliseno. 2019. "Symptomless reaction of Sechium edule (Jacq.) Sw. to Verticillium dahliae Kleb." Journal of Plant Pathology 101, no. 4: 1195-1197.
In the last century, the banana crop and industry experienced dramatic losses due to an epidemic of Fusarium wilt of banana (FWB), caused by Fusarium oxysporum f.sp. cubense (Foc) race 1. An even more dramatic menace is now feared due to the spread of Foc tropical race 4. Plant genetic resistance is generally considered as the most plausible strategy for controlling effectively such a devastating disease, as occurred for the first round of FWB epidemic. Nevertheless, with at least 182 articles published since 1970, biological control represents a large body of knowledge on FWB. Remarkably, many studies deal with biological control agents (BCAs) that reached the field-testing stage and even refer to high effectiveness. Some selected BCAs have been repeatedly assayed in independent trials, suggesting their promising value. Overall under field conditions, FWB has been controlled up to 79% by using Pseudomonas spp. strains, and up to 70% by several endophytes and Trichoderma spp. strains. Lower biocontrol efficacy (42–55%) has been obtained with arbuscular mycorrhizal fungi, Bacillus spp., and non-pathogenic Fusarium strains. Studies on Streptomyces spp. have been mostly limited to in vitro conditions so far, with very few pot-experiments, and none conducted in the field. The BCAs have been applied with diverse procedures (e.g., spore suspension, organic amendments, bioformulations, etc.) and at different stages of plant development (i.e., in vitro, nursery, at transplanting, post-transplanting), but there has been no evidence for a protocol better than another. Nonetheless, new bioformulation technologies (e.g., nanotechnology, formulation of microbial consortia and/or their metabolites, etc.) and tailor-made consortia of microbial strains should be encouraged. In conclusion, the literature offers many examples of promising BCAs, suggesting that biocontrol can greatly contribute to limit the damage caused by FWB. More efforts should be done to further validate the currently available outcomes, to deepen the knowledge on the most valuable BCAs, and to improve their efficacy by setting up effective formulations, application protocols, and integrated strategies.
Giovanni Bubici; Manoj Kaushal; Maria Isabella Prigigallo; Carmen Gómez-Lama Cabanás; Jesús Mercado-Blanco. Biological Control Agents Against Fusarium Wilt of Banana. Frontiers in Microbiology 2019, 10, 616 .
AMA StyleGiovanni Bubici, Manoj Kaushal, Maria Isabella Prigigallo, Carmen Gómez-Lama Cabanás, Jesús Mercado-Blanco. Biological Control Agents Against Fusarium Wilt of Banana. Frontiers in Microbiology. 2019; 10 ():616.
Chicago/Turabian StyleGiovanni Bubici; Manoj Kaushal; Maria Isabella Prigigallo; Carmen Gómez-Lama Cabanás; Jesús Mercado-Blanco. 2019. "Biological Control Agents Against Fusarium Wilt of Banana." Frontiers in Microbiology 10, no. : 616.
BACKGROUND Ozonated water (O3wat) soil drench and/or foliar spray applications, were evaluated for their potential to control the root‐knot nematode Meloidogyne incognita (RKN) and the airborne pathogen Tomato spotted wilt virus (TSWV) in tomato. We investigated how O3wat modulates the SA/JA/ET signalling network in the host, locally and systemically, to induce resistance to nematode and virus. RESULTS The application as soil drench was effective in reducing the number of galls and egg masses, but did not reduce the incidence and severity of TSWV infection. Conversely, O3wat applied by foliar spray decreased TSWV disease incidence and severity (‐20%), but was not able to control M. incognita infection. SA‐related genes were generally up‐regulated in both locally treated and systemically reached tissues, showing a positive action of the O3wat treatment on SA signalling. Both O3wat application methods did not alter significantly JA‐related gene expression in either direction. ET‐related genes were differentially regulated by root or leaf treatments, indicating that O3wat may have different effects on ET‐mediated signalling in different organs. JA/ET/SA related pathways were differentially modulated by O3wat in the presence of either RKN or TSWV. CONCLUSION O3wat had a higher efficacy when applied directly to the organs challenged by the pathogens, although it was potentially able to stimulate defence responses through the activation of SA signalling. Due to its safety and effectiveness in controlling nematode and virus infections, O3wat can be considered as a possible alternative tool for sustainable disease management practices. This article is protected by copyright. All rights reserved.
Maria Isabella Prigigallo; Maria Teresa Melillo; Giovanni Bubici; Petre I. Dobrev; Radomira Vankova; Fabrizio Cillo; Pasqua Veronico. Ozone treatments activate defence responses against Meloidogyne incognita and Tomato spotted wilt virus in tomato. Pest Management Science 2019, 75, 2251 -2263.
AMA StyleMaria Isabella Prigigallo, Maria Teresa Melillo, Giovanni Bubici, Petre I. Dobrev, Radomira Vankova, Fabrizio Cillo, Pasqua Veronico. Ozone treatments activate defence responses against Meloidogyne incognita and Tomato spotted wilt virus in tomato. Pest Management Science. 2019; 75 (8):2251-2263.
Chicago/Turabian StyleMaria Isabella Prigigallo; Maria Teresa Melillo; Giovanni Bubici; Petre I. Dobrev; Radomira Vankova; Fabrizio Cillo; Pasqua Veronico. 2019. "Ozone treatments activate defence responses against Meloidogyne incognita and Tomato spotted wilt virus in tomato." Pest Management Science 75, no. 8: 2251-2263.
Leaf blight caused by Itersonilia perplexans Derx is commonly observed on dill (Anethum graveolens L.) at the crop maturity stage. In the fields of southern Italy, I. perplexans attacks begin in late autumn, when the weather is cool and humid. In laboratory, the fungal growth rate was maximum at 20 °C, the ballistoconidia production was null at temperatures of 25 °C or higher, and growth was interrupted at 30 °C or above. It is difficult to manage the disease because very few fungicides are admitted for use on dill. Therefore, we screened in vitro several fungicides for their toxicity against I. perplexans, and discovered the high effectiveness of difenoconazole, with EC50 and EC95 of 0.5 and 0.95 μg mL−1, respectively, both for mycelium growth and ballistoconidia production. Ciprodinil+fludioxonil, azoxystrobin (both with EC50 = 0.69 μg mL−1) and boscalid (EC50 = 7.32 μg mL−1) were toxic to I. perplexans, but did not suppress completely the pathogen even at doses of 10,000 μg mL−1. Mancozeb+metalaxil showed EC50 of 15.5 μg mL−1 and completely suppressed the fungus at 100 μg mL−1. Copper oxychloride was toxic only at doses higher than 100 μg mL−1, and sulphur did not affect the pathogen growth. Therefore, difenoconazole is worthy of further evaluations in the field for the control of leaf blight of dill caused by I. perplexans.
Giovanni Bubici; Maria Isabella Prigigallo; Mario Amenduni. In vitro effectiveness of difenoconazole against Itersonilia perplexans Derx. Journal of Plant Pathology 2018, 101, 355 -360.
AMA StyleGiovanni Bubici, Maria Isabella Prigigallo, Mario Amenduni. In vitro effectiveness of difenoconazole against Itersonilia perplexans Derx. Journal of Plant Pathology. 2018; 101 (2):355-360.
Chicago/Turabian StyleGiovanni Bubici; Maria Isabella Prigigallo; Mario Amenduni. 2018. "In vitro effectiveness of difenoconazole against Itersonilia perplexans Derx." Journal of Plant Pathology 101, no. 2: 355-360.
RNA silencing plays a critical role in plant resistance against viruses. To counteract host defense, plant viruses encode viral suppressors of RNA silencing (VSRs) that interfere with the cellular silencing machinery through various mechanisms not always well understood. We examined the role of Mungbean yellow mosaic virus (MYMV) AC4 and showed that it is essential for infectivity but not for virus replication. It acts as a determinant of pathogenicity and counteracts virus induced gene silencing by strongly suppressing the systemic phase of silencing whereas it does not interfere with local production of siRNA. We demonstrate the ability of AC4 to bind native 21–25 nt siRNAs in vitro by electrophoretic mobility shift assay. While most of the known VSRs have cytoplasmic localization, we observed that despite its hydrophilic nature and the absence of trans-membrane domain, MYMV AC4 specifically accumulates to the plasma membrane (PM). We show that AC4 binds to PM via S-palmitoylation, a process of post-translational modification regulating membrane–protein interactions, not known for plant viral protein before. When localized to the PM, AC4 strongly suppresses systemic silencing whereas its delocalization impairs VSR activity of the protein. We also show that AC4 interacts with the receptor-like kinase (RLK) BARELY ANY MERISTEM 1 (BAM1), a positive regulator of the cell-to-cell movement of RNAi. The absolute requirement of PM localization for direct silencing suppression activity of AC4 is novel and intriguing. We discuss a possible model of action: palmitoylated AC4 anchors to the PM by means of palmitate to acquire the optimal conformation to bind siRNAs, hinder their systemic movement and hence suppress the spread of the PTGS signal in the plant.
Anna Vittoria Carluccio; Maria Isabella Prigigallo; Tabata Rosas-Diaz; Rosa Lozano-Duran; Livia Stavolone. S‐acylation mediates Mungbean yellow mosaic virus AC4 localization to the plasma membrane and in turns gene silencing suppression. PLOS Pathogens 2018, 14, e1007207 .
AMA StyleAnna Vittoria Carluccio, Maria Isabella Prigigallo, Tabata Rosas-Diaz, Rosa Lozano-Duran, Livia Stavolone. S‐acylation mediates Mungbean yellow mosaic virus AC4 localization to the plasma membrane and in turns gene silencing suppression. PLOS Pathogens. 2018; 14 (8):e1007207.
Chicago/Turabian StyleAnna Vittoria Carluccio; Maria Isabella Prigigallo; Tabata Rosas-Diaz; Rosa Lozano-Duran; Livia Stavolone. 2018. "S‐acylation mediates Mungbean yellow mosaic virus AC4 localization to the plasma membrane and in turns gene silencing suppression." PLOS Pathogens 14, no. 8: e1007207.
Alternaria brown spot is one of the most important diseases of tangerines and their hybrids worldwide. Recently, outbreaks in Mediterranean areas related to susceptible cultivars, refocused attention on the disease. Twenty representatives were selected from a collection of 180 isolates of Alternaria spp. from citrus leaves and fruit. They were characterized along with reference strains of Alternaria spp. Micro- and macroscopic characteristics separated most Alternaria isolates into six morphotypes referable to A. alternata (5) and A. arborescens (1). Phylogenetic analyses, based on endopolygalacturonase (endopg) and internal transcribed spacer (ITS), confirmed this finding. Moreover, a five-gene phylogeny including two anonymous genomics regions (OPA 1–3 and OPA 2–1), and the beta-tubulin gene (ß-tub), produced a further clustering of A. alternata into three clades. This analysis suggested the existence of intra-species molecular variability. Investigated isolates showed different levels of virulence on leaves and fruit. In particular, the pathogenicity on fruit seemed to be correlated with the tissue of isolation and the clade. The toxigenic behavior of Alternaria isolates was also investigated, with tenuazonic acid (TeA) being the most abundant mycotoxin (0.2–20 mg/L). Isolates also synthesized the mycotoxins alternariol (AOH), its derivate alternariol monomethyl ether (AME), and altenuene (ALT), although to a lesser extent. AME production significantly varied among the six morphotypes. The expression of pksJ/pksH, biosynthetic genes of AOH/AME, was not correlated with actual toxin production, but it was significantly different between the two genotypes and among the four clades. Finally, ten isolates proved to express the biosynthetic genes of ACTT1 phytotoxin, and thus to be included in the Alternaria pathotype tangerine. A significant correlation between pathogenicity on leaves and ACTT1 gene expression was recorded. The latter was significantly dependent on geographical origin. The widespread occurrence of Alternaria spp. on citrus fruit and their ability to produce mycotoxins might represent a serious concern for producers and consumers.
Francesca Garganese; Leonardo Schena; Ilenia Siciliano; Maria Isabella Prigigallo; Davide Spadaro; Anna De Grassi; Antonio Ippolito; Simona Marianna Sanzani. Characterization of Citrus-Associated Alternaria Species in Mediterranean Areas. PLOS ONE 2016, 11, e0163255 -e0163255.
AMA StyleFrancesca Garganese, Leonardo Schena, Ilenia Siciliano, Maria Isabella Prigigallo, Davide Spadaro, Anna De Grassi, Antonio Ippolito, Simona Marianna Sanzani. Characterization of Citrus-Associated Alternaria Species in Mediterranean Areas. PLOS ONE. 2016; 11 (9):e0163255-e0163255.
Chicago/Turabian StyleFrancesca Garganese; Leonardo Schena; Ilenia Siciliano; Maria Isabella Prigigallo; Davide Spadaro; Anna De Grassi; Antonio Ippolito; Simona Marianna Sanzani. 2016. "Characterization of Citrus-Associated Alternaria Species in Mediterranean Areas." PLOS ONE 11, no. 9: e0163255-e0163255.
A metabarcoding method based on genus-specific primers and 454 pyrosequencing was utilized to investigate the genetic diversity of Phytophthora spp. in soil and root samples of potted plants, from eight nurseries. Pyrosequencing enabled the detection of 25 Phytophthora phylotypes distributed in seven different clades and provided a much higher resolution than a corresponding cloning/Sanger sequencing approach. Eleven of these phylotypes, including P. cactorum, P. citricola s.str., P. palmivora, P. palmivora-like, P. megasperma or P. gonapodyides, P. ramorum, and five putative new Phytophthora species phylogenetically related to clades 1, 2, 4, 6, and 7 were detected only with the 454 pyrosequencing approach. We also found an additional 18 novel records of a phylotype in a particular nursery that were not detected with cloning/Sanger sequencing. Several aspects confirmed the reliability of the method: (i) many identical sequence types were identified independently in different nurseries, (ii) most sequence types identified with 454 pyrosequencing were identical to those from the cloning/Sanger sequencing approach and/or perfectly matched GenBank deposited sequences, and (iii) the divergence noted between sequence types of putative new Phytophthora species and all other detected sequences was sufficient to rule out sequencing errors. The proposed method represents a powerful tool to study Phytophthora diversity providing that particular attention is paid to the analysis of 454 pyrosequencing raw read sequences and to the identification of sequence types.
Maria I. Prigigallo; Ahmed Abdelfattah; Santa O. Cacciola; Roberto Faedda; Simona M. Sanzani; David E. L. Cooke; L. Schena. Metabarcoding Analysis of Phytophthora Diversity Using Genus-Specific Primers and 454 Pyrosequencing. Phytopathology® 2016, 106, 305 -313.
AMA StyleMaria I. Prigigallo, Ahmed Abdelfattah, Santa O. Cacciola, Roberto Faedda, Simona M. Sanzani, David E. L. Cooke, L. Schena. Metabarcoding Analysis of Phytophthora Diversity Using Genus-Specific Primers and 454 Pyrosequencing. Phytopathology®. 2016; 106 (3):305-313.
Chicago/Turabian StyleMaria I. Prigigallo; Ahmed Abdelfattah; Santa O. Cacciola; Roberto Faedda; Simona M. Sanzani; David E. L. Cooke; L. Schena. 2016. "Metabarcoding Analysis of Phytophthora Diversity Using Genus-Specific Primers and 454 Pyrosequencing." Phytopathology® 106, no. 3: 305-313.
The genetic diversity of Phytophthora spp. was investigated in potted ornamental and fruit tree species. A metagenomic approach was used, based on a semi‐nested PCR with Phytophthora genus‐specific primers targeting the ITS1 region of the rDNA. More than 50 ITS1 sequence types (STs) representing at least 15 distinct Phytophthora taxa were detected. Nine had ITS sequences that grouped them in defined taxonomic groups (P. nicotianae, P. citrophthora, P. meadii, P. taxon Pgchlamydo, P. cinnamomi, P. parvispora, P. cambivora, P. niederhauserii and P. lateralis) whereas three phylotypes were associated to two or more taxa (P. citricola taxon E or III; P. pseudosyringae, P. ilicis or P. nemorosa; and P. cryptogea, P. erythroseptica, P. himalayensis or P. sp. ‘kelmania’) that can be challenging to resolve with ITS1 sequences alone. Three additional phylotypes were considered as representatives of novel Phytophthora taxa and defined as P. meadii‐like, P. cinnamomi‐like and P. niederhauserii‐like. Furthermore, the analyses highlighted a very complex assemblage of Phytophthora taxa in ornamental nurseries within a limited geographic area and provided some indications of structure amongst populations of P. nicotianae (the most prevalent taxon) and other taxa. Data revealed new host–pathogen combinations, evidence of new species previously unreported in Italy (P. lateralis) or Europe (P. meadii) and phylotypes representative of species that remain to be taxonomically defined. Furthermore, the results reinforced the primary role of plant nurseries in favouring the introduction, dissemination and evolution of Phytophthora species.
M. I. Prigigallo; S. Mosca; S. O. Cacciola; D. E. L. Cooke; Leonardo Schena. Molecular analysis ofPhytophthoradiversity in nursery-grown ornamental and fruit plants. Plant Pathology 2015, 64, 1308 -1319.
AMA StyleM. I. Prigigallo, S. Mosca, S. O. Cacciola, D. E. L. Cooke, Leonardo Schena. Molecular analysis ofPhytophthoradiversity in nursery-grown ornamental and fruit plants. Plant Pathology. 2015; 64 (6):1308-1319.
Chicago/Turabian StyleM. I. Prigigallo; S. Mosca; S. O. Cacciola; D. E. L. Cooke; Leonardo Schena. 2015. "Molecular analysis ofPhytophthoradiversity in nursery-grown ornamental and fruit plants." Plant Pathology 64, no. 6: 1308-1319.