1
|
Bodino N, Barbera R, González-Mas N, Demichelis S, Bosco D, Dolci P. Activity of natural occurring entomopathogenic fungi on nymphal and adult stages of Philaenus spumarius. J Invertebr Pathol 2024; 204:108078. [PMID: 38438078 DOI: 10.1016/j.jip.2024.108078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 01/10/2024] [Accepted: 02/25/2024] [Indexed: 03/06/2024]
Abstract
The spittlebug Philaenus spumarius (Hemiptera: Aphrophoridae) is the predominant vector of Xylella fastidiosa (Xanthomonadales: Xanthomonadaceae) in Apulia, Italy and the rest of Europe. Current control strategies of the insect vector rely on mechanical management of nymphal stages and insecticide application against adult populations. Entomopathogenic fungi (EPF) are biological control agents naturally attacking spittlebugs and may effectively reduce population levels of host species. Different experimental trials in controlled conditions have been performed to i) identify naturally occurring EPF on P, spumarius in Northwestern Italy, and ii) evaluate the potential for biocontrol of the isolated strains on both nymphal and adult stages of the spittlebug. Four EPF species were isolated from dead P. spumarius collected in semi-field conditions: Beauveria bassiana, Conidiobolus coronatus, Fusarium equiseti and Lecanicillium aphanocladii. All the fungal isolates showed entomopathogenic potential against nymphal stages of P. spumarius (≈ 45 % mortality), except for F. equiseti, in preliminary trials. No induced mortality was observed on adult stage. Lecanicillium aphanocladii was the most promising fungus and its pathogenicity against spittlebug nymphs was further tested in different formulations (conidia vs blastospores) and with natural adjuvants. Blastospore formulation was the most effective in killing nymphal instars and reducing the emergence rate of P, spumarius adults, reaching mortality levels (90%) similar to those of the commercial product Naturalis®, while no or adverse effect of natural adjuvants was recorded. The encouraging results of this study pave way for testing EPF isolates against P, spumarius in field conditions and find new environmentally friendly control strategies against insect vectors of X. fastidiosa.
Collapse
Affiliation(s)
- Nicola Bodino
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi di Torino, Largo Paolo Braccini, 2, 10095 Grugliasco, TO, Italy; CNR-Istituto Per La Protezione Sostenibile Delle Piante, Strada Delle Cacce, 73, 10135 Torino, Italy.
| | - Riccardo Barbera
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi di Torino, Largo Paolo Braccini, 2, 10095 Grugliasco, TO, Italy.
| | - Natalia González-Mas
- Department of Agronomy, María de Maeztu Excellence Unit DAUCO, ETSIAM, University of Cordoba, C4 Building, Celestino Mutis, Campus de Rabanales, 14071, Cordoba, Spain.
| | - Stefano Demichelis
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi di Torino, Largo Paolo Braccini, 2, 10095 Grugliasco, TO, Italy.
| | - Domenico Bosco
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi di Torino, Largo Paolo Braccini, 2, 10095 Grugliasco, TO, Italy; CNR-Istituto Per La Protezione Sostenibile Delle Piante, Strada Delle Cacce, 73, 10135 Torino, Italy.
| | - Paola Dolci
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi di Torino, Largo Paolo Braccini, 2, 10095 Grugliasco, TO, Italy.
| |
Collapse
|
2
|
Serio F, Imbriani G, Girelli CR, Miglietta PP, Scortichini M, Fanizzi FP. A Decade after the Outbreak of Xylella fastidiosa subsp. pauca in Apulia (Southern Italy): Methodical Literature Analysis of Research Strategies. PLANTS (BASEL, SWITZERLAND) 2024; 13:1433. [PMID: 38891241 PMCID: PMC11175074 DOI: 10.3390/plants13111433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/17/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024]
Abstract
In 2013, an outbreak of Xylella fastidiosa (Xf) was identified for the first time in Europe, in the extreme south of Italy (Apulia, Salento territory). The locally identified subspecies pauca turned out to be lethal for olive trees, starting an unprecedented phytosanitary emergency for one of the most iconic cultivations of the Mediterranean area. Xf pauca (Xfp) is responsible for a severe disease, the olive quick decline syndrome (OQDS), spreading epidemically and with dramatic impact on the agriculture, the landscape, the tourism and the cultural heritage of this region. The bacterium, transmitted by insects that feed on xylem sap, causes rapid wilting in olive trees due to biofilm formation, which obstructs the plant xylematic vessels. The aim of this review is to perform a thorough analysis that offers a general overview of the published work, from 2013 to December 2023, related to the Xfp outbreak in Apulia. This latter hereto has killed millions of olive trees and left a ghostly landscape with more than 8000 square kilometers of infected territory, that is 40% of the region. The majority of the research efforts made to date to combat Xfp in olive plants are listed in the present review, starting with the early attempts to identify the bacterium, the investigations to pinpoint and possibly control the vector, the assessment of specific diagnostic techniques and the pioneered therapeutic approaches. Interestingly, according to the general set criteria for the preliminary examination of the accessible scientific literature related to the Xfp outbreak on Apulian olive trees, fewer than 300 papers can be found over the last decade. Most of them essentially emphasize the importance of developing diagnostic tools that can identify the disease early, even when infected plants are still asymptomatic, in order to reduce the risk of infection for the surrounding plants. On the other hand, in the published work, the diagnostic focus (57%) overwhelmingly encompasses all other possible investigation goals such as vectors, impacts and possible treatments. Notably, between 2013 and 2023, only 6.3% of the literature reports addressing the topic of Xfp in Apulia were concerned with the application of specific treatments against the bacterium. Among them, those reporting field trials on infected plants, including simple pruning indications, were further limited (6%).
Collapse
Affiliation(s)
- Francesca Serio
- Department of Biological and Environmental Sciences and Technology, University of Salento, 73100 Lecce, Italy; (F.S.); (G.I.); (C.R.G.); (P.P.M.)
| | - Giovanni Imbriani
- Department of Biological and Environmental Sciences and Technology, University of Salento, 73100 Lecce, Italy; (F.S.); (G.I.); (C.R.G.); (P.P.M.)
| | - Chiara Roberta Girelli
- Department of Biological and Environmental Sciences and Technology, University of Salento, 73100 Lecce, Italy; (F.S.); (G.I.); (C.R.G.); (P.P.M.)
| | - Pier Paolo Miglietta
- Department of Biological and Environmental Sciences and Technology, University of Salento, 73100 Lecce, Italy; (F.S.); (G.I.); (C.R.G.); (P.P.M.)
| | - Marco Scortichini
- Council for Agricultural Research and Economics (CREA)-Research Centre for Olive, Fruit and Citrus Crops, Via di Fioranello, 52, 00134 Roma, Italy;
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technology, University of Salento, 73100 Lecce, Italy; (F.S.); (G.I.); (C.R.G.); (P.P.M.)
| |
Collapse
|
3
|
De La Fuente L, Navas-Cortés JA, Landa BB. Ten Challenges to Understanding and Managing the Insect-Transmitted, Xylem-Limited Bacterial Pathogen Xylella fastidiosa. PHYTOPATHOLOGY 2024; 114:869-884. [PMID: 38557216 DOI: 10.1094/phyto-12-23-0476-kc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
An unprecedented plant health emergency in olives has been registered over the last decade in Italy, arguably more severe than what occurred repeatedly in grapes in the United States in the last 140 years. These emergencies are epidemics caused by a stealthy pathogen, the xylem-limited, insect-transmitted bacterium Xylella fastidiosa. Although these epidemics spurred research that answered many questions about the biology and management of this pathogen, many gaps in knowledge remain. For this review, we set out to represent both the U.S. and European perspectives on the most pressing challenges that need to be addressed. These are presented in 10 sections that we hope will stimulate discussion and interdisciplinary research. We reviewed intrinsic problems that arise from the fastidious growth of X. fastidiosa, the lack of specificity for insect transmission, and the economic and social importance of perennial mature woody plant hosts. Epidemiological models and predictions of pathogen establishment and disease expansion, vital for preparedness, are based on very limited data. Most of the current knowledge has been gathered from a few pathosystems, whereas several hundred remain to be studied, probably including those that will become the center of the next epidemic. Unfortunately, aspects of a particular pathosystem are not always transferable to others. We recommend diversification of research topics of both fundamental and applied nature addressing multiple pathosystems. Increasing preparedness through knowledge acquisition is the best strategy to anticipate and manage diseases caused by this pathogen, described as "the most dangerous plant bacterium known worldwide."
Collapse
Affiliation(s)
- Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A
| | - Juan A Navas-Cortés
- Department of Crop Protection. Institute for Sustainable Agriculture (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Córdoba, Spain
| | - Blanca B Landa
- Department of Crop Protection. Institute for Sustainable Agriculture (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Córdoba, Spain
| |
Collapse
|
4
|
Giménez-Romero À, Iturbide M, Moralejo E, Gutiérrez JM, Matías MA. Global warming significantly increases the risk of Pierce's disease epidemics in European vineyards. Sci Rep 2024; 14:9648. [PMID: 38671045 DOI: 10.1038/s41598-024-59947-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
Pierce's disease (PD) is a vector-borne disease caused by the bacteria Xylella fastidiosa, which affects grapevines in the Americas. Currently, vineyards in continental Europe, the world's largest producer of quality wine, have not yet been affected by PD. However, climate change may alter this situation. Here we incorporate the latest regional climate change projections into a climate-driven epidemiological model to assess the risk of PD epidemics in Europe for different levels of global warming. We found a significant increase in risk above + 2 ∘ C in the main wine-producing regions of France, Italy and Portugal, in addition to a critical tipping point above + 3 ∘ C for the possible spread of PD beyond the Mediterranean. The model identifies decreasing risk trends in Spain, as well as contrasting patterns across the continent with different velocities of risk change and epidemic growth rates. Although there is some uncertainty in model projections over time, spatial patterns of risk are consistent across different climate models. Our study provides a comprehensive analysis of the future of PD at multiple spatial scales (country, Protected Designation of Origin and vineyard), revealing where, why and when PD could become a new threat to the European wine industry.
Collapse
Affiliation(s)
- Àlex Giménez-Romero
- Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, CSIC-UIB), Campus UIB, 07122, Palma de Mallorca, Spain
| | - Maialen Iturbide
- Instituto de Física de Cantabria (IFCA, CSIC-University of Cantabria), Avenida de los Castros, 39005, Santander, Spain
| | - Eduardo Moralejo
- Tragsa, Passatge Cala Figuera 6, 07009, Palma de Mallorca, Spain
| | - José M Gutiérrez
- Instituto de Física de Cantabria (IFCA, CSIC-University of Cantabria), Avenida de los Castros, 39005, Santander, Spain
| | - Manuel A Matías
- Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, CSIC-UIB), Campus UIB, 07122, Palma de Mallorca, Spain.
| |
Collapse
|
5
|
Cameirão C, Costa D, Rufino J, Pereira JA, Lino-Neto T, Baptista P. Diversity, Composition, and Specificity of the Philaenus spumarius Bacteriome. Microorganisms 2024; 12:298. [PMID: 38399702 PMCID: PMC10893442 DOI: 10.3390/microorganisms12020298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/27/2024] [Accepted: 01/28/2024] [Indexed: 02/25/2024] Open
Abstract
Philaenus spumarius (Linnaeus, 1758) (Hemiptera, Aphrophoridae) was recently classified as a pest due to its ability to act as a vector of the phytopathogen Xylella fastidiosa. This insect has been reported to harbour several symbiotic bacteria that play essential roles in P. spumarius health and fitness. However, the factors driving bacterial assemblages remain largely unexplored. Here, the bacteriome associated with different organs (head, abdomen, and genitalia) of males and females of P. spumarius was characterized using culturally dependent and independent methods and compared in terms of diversity and composition. The bacteriome of P. spumarius is enriched in Proteobacteria, Bacteroidota, and Actinobacteria phyla, as well as in Candidatus Sulcia and Cutibacterium genera. The most frequent isolates were Curtobacterium, Pseudomonas, and Rhizobiaceae sp.1. Males display a more diverse bacterial community than females, but no differences in diversity were found in distinct organs. However, the organ shapes the bacteriome structure more than sex, with the Microbacteriaceae family revealing a high level of organ specificity and the Blattabacteriaceae family showing a high level of sex specificity. Several symbiotic bacterial genera were identified in P. spumarius for the first time, including Rhodococcus, Citrobacter, Halomonas, Streptomyces, and Providencia. Differences in the bacterial composition within P. spumarius organs and sexes suggest an adaptation of bacteria to particular insect tissues, potentially shaped by their significance in the life and overall fitness of P. spumarius. Although more research on the bacteria of P. spumarius interactions is needed, such knowledge could help to develop specific bacterial-based insect management strategies.
Collapse
Affiliation(s)
- Cristina Cameirão
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; (C.C.); (J.A.P.)
- Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal;
| | - Daniela Costa
- Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (D.C.); (T.L.-N.)
| | - José Rufino
- Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal;
- Research Centre in Digitalization and Intelligent Robotics (CeDRI), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal
| | - José Alberto Pereira
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; (C.C.); (J.A.P.)
- Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal;
| | - Teresa Lino-Neto
- Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; (D.C.); (T.L.-N.)
| | - Paula Baptista
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; (C.C.); (J.A.P.)
- Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal;
| |
Collapse
|
6
|
Kim DY, Patel SKS, Rasool K, Lone N, Bhatia SK, Seth CS, Ghodake GS. Bioinspired silver nanoparticle-based nanocomposites for effective control of plant pathogens: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168318. [PMID: 37956842 DOI: 10.1016/j.scitotenv.2023.168318] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/15/2023] [Accepted: 11/02/2023] [Indexed: 11/15/2023]
Abstract
Plant pathogens, including bacteria, fungi, and viruses, pose significant challenges to the farming community due to their extensive diversity, the rapidly evolving phenomenon of multi-drug resistance (MDR), and the limited availability of effective control measures. Amid mounting global pressure, particularly from the World Health Organization, to limit the use of antibiotics in agriculture and livestock management, there is increasing consideration of engineered nanomaterials (ENMs) as promising alternatives for antimicrobial applications. Studies focusing on the application of ENMs in the fight against MDR pathogens are receiving increasing attention, driven by significant losses in agriculture and critical knowledge gaps in this crucial field. In this review, we explore the potential contributions of silver nanoparticles (AgNPs) and their nanocomposites in combating plant diseases, within the emerging interdisciplinary arena of nano-phytopathology. AgNPs and their nanocomposites are increasingly acknowledged as promising countermeasures against plant pathogens, owing to their unique physicochemical characteristics and inherent antimicrobial properties. This review explores recent advancements in engineered nanocomposites, highlights their diverse mechanisms for pathogen control, and draws attention to their potential in antibacterial, antifungal, and antiviral applications. In the discussion, we briefly address three crucial dimensions of combating plant pathogens: green synthesis approaches, toxicity-environmental concerns, and factors influencing antimicrobial efficacy. Finally, we outline recent advancements, existing challenges, and prospects in scholarly research to facilitate the integration of nanotechnology across interdisciplinary fields for more effective treatment and prevention of plant diseases.
Collapse
Affiliation(s)
- Dae-Young Kim
- Department of Biological and Environmental Science, Dongguk University-Seoul, 32 Dongguk-ro, Ilsandong-gu, Goyang-si 10326, Gyeonggi-do, Republic of Korea
| | | | - Kashif Rasool
- Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Nasreena Lone
- School of Allied Healthcare and Sciences, JAIN Deemed University, Whitefield, Bangalore 560066, India
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | | | - Gajanan Sampatrao Ghodake
- Department of Biological and Environmental Science, Dongguk University-Seoul, 32 Dongguk-ro, Ilsandong-gu, Goyang-si 10326, Gyeonggi-do, Republic of Korea.
| |
Collapse
|
7
|
Ahmed E, Musio B, Todisco S, Mastrorilli P, Gallo V, Saponari M, Nigro F, Gualano S, Santoro F. Non-Targeted Spectranomics for the Early Detection of Xylella fastidiosa Infection in Asymptomatic Olive Trees, cv. Cellina di Nardò. Molecules 2023; 28:7512. [PMID: 38005234 PMCID: PMC10672767 DOI: 10.3390/molecules28227512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/31/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Olive quick decline syndrome (OQDS) is a disease that has been seriously affecting olive trees in southern Italy since around 2009. During the disease, caused by Xylella fastidiosa subsp. pauca sequence type ST53 (Xf), the flow of water and nutrients within the trees is significantly compromised. Initially, infected trees may not show any symptoms, making early detection challenging. In this study, young artificially infected plants of the susceptible cultivar Cellina di Nardò were grown in a controlled environment and co-inoculated with additional xylem-inhabiting fungi. Asymptomatic leaves of olive plants at an early stage of infection were collected and analyzed using nuclear magnetic resonance (NMR), hyperspectral reflectance (HSR), and chemometrics. The application of a spectranomic approach contributed to shedding light on the relationship between the presence of specific hydrosoluble metabolites and the optical properties of both asymptomatic Xf-infected and non-infected olive leaves. Significant correlations between wavebands located in the range of 530-560 nm and 1380-1470 nm, and the following metabolites were found to be indicative of Xf infection: malic acid, fructose, sucrose, oleuropein derivatives, and formic acid. This information is the key to the development of HSR-based sensors capable of early detection of Xf infections in olive trees.
Collapse
Affiliation(s)
- Elhussein Ahmed
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via Orabona, 4, I-70125 Bari, Italy; (E.A.); (S.T.); (P.M.); (V.G.)
- International Centre for Advanced Mediterranean Agronomic Studies of Bari (CIHEAM Bari), Via Ceglie 9, 70010 Valenzano, Italy;
| | - Biagia Musio
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via Orabona, 4, I-70125 Bari, Italy; (E.A.); (S.T.); (P.M.); (V.G.)
| | - Stefano Todisco
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via Orabona, 4, I-70125 Bari, Italy; (E.A.); (S.T.); (P.M.); (V.G.)
| | - Piero Mastrorilli
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via Orabona, 4, I-70125 Bari, Italy; (E.A.); (S.T.); (P.M.); (V.G.)
- Innovative Solutions S.r.l.—Spin-Off Company of Polytechnic University of Bari, Zona H 150/B, 70015 Noci, Italy
| | - Vito Gallo
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via Orabona, 4, I-70125 Bari, Italy; (E.A.); (S.T.); (P.M.); (V.G.)
- Innovative Solutions S.r.l.—Spin-Off Company of Polytechnic University of Bari, Zona H 150/B, 70015 Noci, Italy
| | - Maria Saponari
- Istituto Per la Protezione Sostenibile Delle Piante, CNR, Via Amendola 122/D, I-70126 Bari, Italy;
| | - Franco Nigro
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Orabona, 4, I-70125 Bari, Italy;
| | - Stefania Gualano
- International Centre for Advanced Mediterranean Agronomic Studies of Bari (CIHEAM Bari), Via Ceglie 9, 70010 Valenzano, Italy;
| | - Franco Santoro
- International Centre for Advanced Mediterranean Agronomic Studies of Bari (CIHEAM Bari), Via Ceglie 9, 70010 Valenzano, Italy;
| |
Collapse
|
8
|
Bajocco S, Raparelli E, Bregaglio S. Assessing the driving role of the anthropogenic landscape on the distribution of the Xylella fastidiosa-driven "olive quick decline syndrome" in Apulia (Italy). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165231. [PMID: 37392876 DOI: 10.1016/j.scitotenv.2023.165231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/25/2023] [Accepted: 06/28/2023] [Indexed: 07/03/2023]
Abstract
The plant pathogen Xylella fastidiosa (Xf) is a significant threat to various economically important tree cash crops. Although previously found only in the Americas, the bacterium responsible for olive quick decline syndrome was detected in Apulia, Italy, in 2013. Since then, it has spread to approximately 54,000 ha of olive trees in the region, causing dramatic concern throughout the Mediterranean basin. As a result, it is crucial to comprehend its distribution and forecast its potential diffusion. The effect of the anthropogenic component of the landscape on the distribution of Xf remains little explored. The present study used an ecological niche model to identify how different land uses, used as proxies of different levels of human pressure across the Apulia territory, impacted the distribution of the Xf-infected olive trees in 2015-2021. Results demonstrated that the anthropogenic component significantly contributed to the epidemic, with the road system representing the main driver of diffusion and natural/seminatural areas hampering Xf spread at the landscape scale. This evidence highlighted the importance of explicitly considering the effects of the anthropogenic landscape when modelling Xf distribution and support the design of landscape-informed monitoring strategies to prevent Xf spread in Apulia and other Mediterranean countries.
Collapse
Affiliation(s)
- S Bajocco
- Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment (CREA-AA), Italy
| | - E Raparelli
- Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment (CREA-AA), Italy.
| | - S Bregaglio
- Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment (CREA-AA), Italy
| |
Collapse
|
9
|
Sarkar P, Lin CY, Buritica JR, Killiny N, Levy A. Crossing the Gateless Barriers: Factors Involved in the Movement of Circulative Bacteria Within Their Insect Vectors. PHYTOPATHOLOGY 2023; 113:1805-1816. [PMID: 37160668 DOI: 10.1094/phyto-07-22-0249-ia] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Plant bacterial pathogens transmitted by hemipteran vectors pose a large threat to the agricultural industry worldwide. Although virus-vector relationships have been widely investigated, a significant gap exists in our understanding of the molecular interactions between circulative bacteria and their insect vectors, mainly leafhoppers and psyllids. In this review, we will describe how these bacterial pathogens adhere, invade, and proliferate inside their insect vectors. We will also highlight the different transmission routes and molecular factors of phloem-limited bacteria that maintain an effective relationship with the insect host. Understanding the pathogen-vector relationship at the molecular level will help in the management of vector-borne bacterial diseases.
Collapse
Affiliation(s)
- Poulami Sarkar
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850
| | - Chun-Yi Lin
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850
| | - Jacobo Robledo Buritica
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611
| | - Nabil Killiny
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611
| | - Amit Levy
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611
| |
Collapse
|
10
|
Bodino N, Cavalieri V, Dongiovanni C, Saponari M, Bosco D. Bioecological Traits of Spittlebugs and Their Implications for the Epidemiology and Control of the Xylella fastidiosa Epidemic in Apulia (Southern Italy). PHYTOPATHOLOGY 2023; 113:1647-1660. [PMID: 36945728 DOI: 10.1094/phyto-12-22-0460-ia] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Spatial-temporal dynamics of spittlebug populations, together with transmission biology, are of major importance to outline the disease epidemiology of Xylella fastidiosa subsp. pauca in Apulian olive groves. The spread rate of X. fastidiosa is mainly influenced by (i) the pathogen colonization of the host plant; (ii) the acquisition of the pathogen by the vector from an infected plant, and its inoculation to healthy plants; (iii) the vector population dynamics and abundance at different spatial scales; and (iv) the dispersal of the vector. In this contribution we summarize the recent advances in research on insect vectors' traits-points ii, iii, and iv-focusing on those most relevant to X. fastidiosa epidemic in Apulia. Among the vectors' bioecological traits influencing the X. fastidiosa epidemic in olive trees, we emphasize the following: natural infectivity and transmission efficiency, phenological timing of both nymphal and adult stage, the role of seminatural vegetation as a vector reservoir in the agroecosystem and landscape, and preferential and directional dispersal capabilities. Despite the research on X. fastidiosa vectors carried out in Europe in the last decade, key uncertainties on insect vectors remain, hampering a thorough understanding of pathogen epidemiology and the development of effective and targeted management strategies. Our goal is to provide a structured and contextualized review of knowledge on X. fastidiosa vectors' key traits in the Apulian epidemic, highlighting information gaps and stimulating novel research pathways on X. fastidiosa pathosystems in Europe. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Collapse
Affiliation(s)
- Nicola Bodino
- CNR-Istituto per la Protezione Sostenibile delle Piante, 10135 Torino, Italy
| | - Vincenzo Cavalieri
- CNR-Istituto per la Protezione Sostenibile delle Piante, SS Bari, 70126 Bari, Italy
| | - Crescenza Dongiovanni
- CRSFA-Centro di Ricerca, Sperimentazione e Formazione in Agricoltura Basile Caramia, 70010 Locorotondo (BA), Italy
| | - Maria Saponari
- CNR-Istituto per la Protezione Sostenibile delle Piante, SS Bari, 70126 Bari, Italy
| | - Domenico Bosco
- CNR-Istituto per la Protezione Sostenibile delle Piante, 10135 Torino, Italy
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università degli Studi di Torino, 10095 Grugliasco (TO), Italy
| |
Collapse
|
11
|
Vizzarri V, Ienco A, Benincasa C, Perri E, Pucci N, Cesari E, Novellis C, Rizzo P, Pellegrino M, Zaffina F, Lombardo L. Phenolic Extract from Olive Leaves as a Promising Endotherapeutic Treatment against Xylella fastidiosa in Naturally Infected Olea europaea (var. europaea) Trees. BIOLOGY 2023; 12:1141. [PMID: 37627025 PMCID: PMC10452569 DOI: 10.3390/biology12081141] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023]
Abstract
(1) Background: Since 2013, the pathogenic bacterium Xylella fastidiosa has been severely affecting olive production in Apulia, Italy, with consequences for the economy, local culture, landscape and biodiversity. The production of a phenolic extract from fresh olive leaves was employed for endotherapeutic injection into naturally infected olive trees by Xylella fastidiosa in Apulia region, Italy. (2) Methods: The effectiveness of the extract was tested in vitro and in planta in comparison with analogous treatments based on garlic powder and potassium phosphite. (3) Results: The uptake of phenolic compounds from olive leaves through a trunk injection system device resulted in a statistically significant increase in leaf area index and leaf area density, as well as in the growth of newly formed healthy shoots. Plant growth-promoting effects were also observed for potassium phosphite. Moreover, the bacteriostatic activities of the phenolic extract and of the garlic-powder-based solution have been demonstrated in in vitro tests. (4) Conclusions: The results obtained and the contained costs of extraction make the endotherapeutic treatment with phenolic compounds a promising strategy for controlling X fastidiosa to be tested on a larger scale, although the experiments conducted in this study proved not to be suitable for centenary trees.
Collapse
Affiliation(s)
- Veronica Vizzarri
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Annamaria Ienco
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Cinzia Benincasa
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Enzo Perri
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Nicoletta Pucci
- CREA Research Centre for Plant Protection and Certification, 00156 Rome, Italy; (N.P.); (E.C.)
| | - Erica Cesari
- CREA Research Centre for Plant Protection and Certification, 00156 Rome, Italy; (N.P.); (E.C.)
| | - Carmine Novellis
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Pierluigi Rizzo
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Massimiliano Pellegrino
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Francesco Zaffina
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| | - Luca Lombardo
- CREA Research Centre for Olive, Fruit and Citrus Crops, 87036 Rende, Italy; (V.V.); (A.I.); (C.B.); (E.P.); (C.N.); (P.R.); (M.P.); (F.Z.)
| |
Collapse
|
12
|
Verhaegen M, Bergot T, Liebana E, Stancanelli G, Streissl F, Mingeot-Leclercq MP, Mahillon J, Bragard C. On the use of antibiotics to control plant pathogenic bacteria: a genetic and genomic perspective. Front Microbiol 2023; 14:1221478. [PMID: 37440885 PMCID: PMC10333595 DOI: 10.3389/fmicb.2023.1221478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/08/2023] [Indexed: 07/15/2023] Open
Abstract
Despite growing attention, antibiotics (such as streptomycin, oxytetracycline or kasugamycin) are still used worldwide for the control of major bacterial plant diseases. This raises concerns on their potential, yet unknown impact on antibiotic and multidrug resistances and the spread of their genetic determinants among bacterial pathogens. Antibiotic resistance genes (ARGs) have been identified in plant pathogenic bacteria (PPB), with streptomycin resistance genes being the most commonly reported. Therefore, the contribution of mobile genetic elements (MGEs) to their spread among PPB, as well as their ability to transfer to other bacteria, need to be further explored. The only well-documented example of ARGs vector in PPB, Tn5393 and its highly similar variants (carrying streptomycin resistance genes), is concerning because of its presence outside PPB, in Salmonella enterica and Klebsiella pneumoniae, two major human pathogens. Although its structure among PPB is still relatively simple, in human- and animal-associated bacteria, Tn5393 has evolved into complex associations with other MGEs and ARGs. This review sheds light on ARGs and MGEs associated with PPB, but also investigates the potential role of antibiotic use in resistance selection in plant-associated bacteria.
Collapse
Affiliation(s)
- Marie Verhaegen
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Catholic University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
| | - Thomas Bergot
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Catholic University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
| | | | | | | | - Marie-Paule Mingeot-Leclercq
- Cellular and Molecular Pharmacology Unit, Louvain Drug Research Institute, UCLouvain, Woluwe-Saint-Lambert, Belgium
| | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, Catholic University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
| | - Claude Bragard
- Plant Health Laboratory, Earth and Life Institute, UCLouvain, Louvain-la-Neuve, Belgium
| |
Collapse
|
13
|
Morales-Cruz A, Aguirre-Liguori J, Massonnet M, Minio A, Zaccheo M, Cochetel N, Walker A, Riaz S, Zhou Y, Cantu D, Gaut BS. Multigenic resistance to Xylella fastidiosa in wild grapes (Vitis sps.) and its implications within a changing climate. Commun Biol 2023; 6:580. [PMID: 37253933 DOI: 10.1038/s42003-023-04938-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/12/2023] [Indexed: 06/01/2023] Open
Abstract
Xylella fastidiosa is a bacterium that infects crops like grapevines, coffee, almonds, citrus and olives. There is little understanding of the genes that contribute to plant resistance, the genomic architecture of resistance, and the potential role of climate in shaping resistance, in part because major crops like grapevines (Vitis vinifera) are not resistant to the bacterium. Here we study a wild grapevine species, V. arizonica, that segregates for resistance. Using genome-wide association, we identify candidate resistance genes. Resistance-associated kmers are shared with a sister species of V. arizonica but not with more distant species, suggesting that resistance evolved more than once. Finally, resistance is climate dependent, because individuals from low ( < 10 °C) temperature locations in the wettest quarter were typically susceptible to infection, likely reflecting a lack of pathogen pressure in colder climates. In fact, climate is as effective a predictor of resistance phenotypes as some genetic markers. We extend our climate observations to additional crops, predicting that increased pathogen pressure is more likely for grapevines and almonds than some other susceptible crops.
Collapse
Affiliation(s)
- Abraham Morales-Cruz
- U.S. Department of Energy, Joint Genome Institute, Lawrence Berkeley National Lab, Berkeley, CA, 94720, USA
| | - Jonas Aguirre-Liguori
- Dept. of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Mélanie Massonnet
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA
| | - Andrea Minio
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA
| | - Mirella Zaccheo
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA
| | - Noe Cochetel
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA
| | - Andrew Walker
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA
| | - Summaira Riaz
- San Joaquin Valley Agricultural Center, United States Dept of Agriculture, Parlier, CA, USA
| | - Yongfeng Zhou
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
- Agricultural Genomics Institute at Shenzhen, The Chinese Academy of Agricultural Sciences, No. 7 Pengfei Road, Shenzen, 518120, China.
| | - Dario Cantu
- Dept. of Viticulture and Enology, University of California, Davis, CA, USA.
- Dept. of Viticulture and Enology, One Shields Avenue, University of California Davis, Davis, CA, 95616-5270, USA.
| | - Brandon S Gaut
- Dept. of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA.
- Dept. of Ecology and Evolutionary Biology, 321 Steinhaus Hall UC Irvine, Irvine, CA, 92617-2525, USA.
| |
Collapse
|
14
|
Blonda P, Tarantino C, Scortichini M, Maggi S, Tarantino M, Adamo M. Satellite monitoring of bio-fertilizer restoration in olive groves affected by Xylella fastidiosa subsp. pauca. Sci Rep 2023; 13:5695. [PMID: 37029149 PMCID: PMC10082035 DOI: 10.1038/s41598-023-32170-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/23/2023] [Indexed: 04/09/2023] Open
Abstract
Xylella fastidiosa subsp. pauca (Xfp), has attacked the olive trees in Southern Italy with severe impacts on the olive agro-ecosystem. To reduce both the Xfp cell concentration and the disease symptom, a bio-fertilizer restoration technique has been used. Our study applied multi-resolution satellite data to evaluate the effectiveness of such technique at both field and tree scale. For field scale, a time series of High Resolution (HR) Sentinel-2 images, acquired in the months of July and August from 2015 to 2020, was employed. First, four spectral indices from treated and untreated fields were compared. Then, their trends were correlated to meteo-events. For tree-scale, Very High Resolution (VHR) Pléiades images were selected at the closest dates of the Sentinel-2 data to investigate the response to treatments of each different cultivar. All indices from HR and VHR images were higher in treated fields than in those untreated. The analysis of VHR indices revealed that Oliarola Salentina can respond better to treatments than Leccino and Cellina cultivars. All findings were in agreement with in-field PCR results. Hence, HR data could be used to evaluate plant conditions at field level after treatments, while VHR imagery could be used to optimize treatment doses per cultivar.
Collapse
Affiliation(s)
- Palma Blonda
- Institute of Atmospheric Pollution Research, National Research Council of Italy, c/o Interateneo Physics Department, Via Amendola 173, 70126, Bari, Italy.
| | - Cristina Tarantino
- Institute of Atmospheric Pollution Research, National Research Council of Italy, c/o Interateneo Physics Department, Via Amendola 173, 70126, Bari, Italy
| | - Marco Scortichini
- Research Centre for Olive, Fruit and Citrus Crops, Council for Agricultural Research and Economics, Via di Fioranello 52, 00134, Rome, Italy
| | - Sabino Maggi
- Institute of Atmospheric Pollution Research, National Research Council of Italy, c/o Interateneo Physics Department, Via Amendola 173, 70126, Bari, Italy
| | - Maria Tarantino
- Interateneo Physics Department, University of Bari, Via Amendola 173, 70126, Bari, Italy
| | - Maria Adamo
- Institute of Atmospheric Pollution Research, National Research Council of Italy, c/o Interateneo Physics Department, Via Amendola 173, 70126, Bari, Italy
| |
Collapse
|
15
|
Rossi JP, Rasplus JY. Climate change and the potential distribution of the glassy-winged sharpshooter (Homalodisca vitripennis), an insect vector of Xylella fastidiosa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160375. [PMID: 36423847 DOI: 10.1016/j.scitotenv.2022.160375] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/17/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
Biological invasions represent a major threat for biodiversity and agriculture. Despite efforts to restrict the spread of alien species, preventing their introduction remains the best strategy for an efficient control. In that context preparedness of phytosanitary authorities is very important and estimating the geographical range of alien species becomes a key information. The present study investigates the potential geographical range of the glassy-winged sharpshooter (Homalodisca vitripennis), a very efficient insect vector of Xylella fastidiosa, one of the most dangerous plant-pathogenic bacteria worldwide. We use species distribution modeling (SDM) to analyse the climate factors driving the insect distribution and we evaluate its potential distribution in its native range (USA) and in Europe according to current climate and different scenarios of climate change: 6 General Circulation Models (GCM), 4 shared socioeconomic pathways of gas emission and 4 time periods (2030, 2050, 2070, 2090). The first result is that the climate conditions of the European continent are suitable to the glassy-winged sharpshooter, in particular around the Mediterranean basin where X. fastidiosa is present. Projections according to future climate conditions indicate displacement of climatically suitable areas towards the north in both North America and Europe. Globally, suitable areas will decrease in North America and increase in Europe in the coming decades. SDM outputs vary according to the GCM considered and this variability indicated areas of uncertainty in the species potential range. Both potential distribution and its uncertainty associated to future climate projections are important information for improved preparedness of phytosanitary authorities.
Collapse
Affiliation(s)
- Jean-Pierre Rossi
- CBGP (Centre de Biologie pour la Gestion des Populations), INRAE, CIRAD, IRD, Institut Agro, Montpellier, France.
| | - Jean-Yves Rasplus
- CBGP (Centre de Biologie pour la Gestion des Populations), INRAE, CIRAD, IRD, Institut Agro, Montpellier, France.
| |
Collapse
|
16
|
Anguita-Maeso M, Navas-Cortés JA, Landa BB. Insights into the Methodological, Biotic and Abiotic Factors Influencing the Characterization of Xylem-Inhabiting Microbial Communities of Olive Trees. PLANTS (BASEL, SWITZERLAND) 2023; 12:912. [PMID: 36840260 PMCID: PMC9967459 DOI: 10.3390/plants12040912] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/08/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
Vascular pathogens are the causal agents of some of the most devastating plant diseases in the world, which can cause, under specific conditions, the destruction of entire crops. These plant pathogens activate a range of physiological and immune reactions in the host plant following infection, which may trigger the proliferation of a specific microbiome to combat them by, among others, inhibiting their growth and/or competing for space. Nowadays, it has been demonstrated that the plant microbiome can be modified by transplanting specific members of the microbiome, with exciting results for the control of plant diseases. However, its practical application in agriculture for the control of vascular plant pathogens is hampered by the limited knowledge of the plant endosphere, and, in particular, of the xylem niche. In this review, we present a comprehensive overview of how research on the plant microbiome has evolved during the last decades to unravel the factors and complex interactions that affect the associated microbial communities and their surrounding environment, focusing on the microbial communities inhabiting the xylem vessels of olive trees (Olea europaea subsp. europaea), the most ancient and important woody crop in the Mediterranean Basin. For that purpose, we have highlighted the role of xylem composition and its associated microorganisms in plants by describing the methodological approaches explored to study xylem microbiota, starting from the methods used to extract xylem microbial communities to their assessment by culture-dependent and next-generation sequencing approaches. Additionally, we have categorized some of the key biotic and abiotic factors, such as the host plant niche and genotype, the environment and the infection with vascular pathogens, that can be potential determinants to critically affect olive physiology and health status in a holobiont context (host and its associated organisms). Finally, we have outlined future directions and challenges for xylem microbiome studies based on the recent advances in molecular biology, focusing on metagenomics and culturomics, and bioinformatics network analysis. A better understanding of the xylem olive microbiome will contribute to facilitate the exploration and selection of specific keystone microorganisms that can live in close association with olives under a range of environmental/agronomic conditions. These microorganisms could be ideal targets for the design of microbial consortia that can be applied by endotherapy treatments to prevent or control diseases caused by vascular pathogens or modify the physiology and growth of olive trees.
Collapse
|
17
|
Lovell-Read FA, Parnell S, Cunniffe NJ, Thompson RN. Using 'sentinel' plants to improve early detection of invasive plant pathogens. PLoS Comput Biol 2023; 19:e1010884. [PMID: 36730434 PMCID: PMC9928126 DOI: 10.1371/journal.pcbi.1010884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 02/14/2023] [Accepted: 01/18/2023] [Indexed: 02/04/2023] Open
Abstract
Infectious diseases of plants present an ongoing and increasing threat to international biosecurity, with wide-ranging implications. An important challenge in plant disease management is achieving early detection of invading pathogens, which requires effective surveillance through the implementation of appropriate monitoring programmes. However, when monitoring relies on visual inspection as a means of detection, surveillance is often hindered by a long incubation period (delay from infection to symptom onset) during which plants may be infectious but not displaying visible symptoms. 'Sentinel' plants-alternative susceptible host species that display visible symptoms of infection more rapidly-could be introduced to at-risk populations and included in monitoring programmes to act as early warning beacons for infection. However, while sentinel hosts exhibit faster disease progression and so allow pathogens to be detected earlier, this often comes at a cost: faster disease progression typically promotes earlier onward transmission. Here, we construct a computational model of pathogen transmission to explore this trade-off and investigate how including sentinel plants in monitoring programmes could facilitate earlier detection of invasive plant pathogens. Using Xylella fastidiosa infection in Olea europaea (European olive) as a current high profile case study, for which Catharanthus roseus (Madagascan periwinkle) is a candidate sentinel host, we apply a Bayesian optimisation algorithm to determine the optimal number of sentinel hosts to introduce for a given sampling effort, as well as the optimal division of limited surveillance resources between crop and sentinel plants. Our results demonstrate that including sentinel plants in monitoring programmes can reduce the expected prevalence of infection upon outbreak detection substantially, increasing the feasibility of local outbreak containment.
Collapse
Affiliation(s)
| | - Stephen Parnell
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Nik J. Cunniffe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Robin N. Thompson
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, United Kingdom
| |
Collapse
|
18
|
Johnson KA, Bock CH, Vinson EL, Brannen PM. Prevalence and Distribution of Phony Peach Disease (Caused by Xylella fastidiosa) in the United States. PLANT DISEASE 2023; 107:326-334. [PMID: 35771113 DOI: 10.1094/pdis-03-22-0653-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Peach is an important specialty fruit crop in the United States, and phony peach disease (PPD), caused by Xylella fastidiosa subsp. multiplex, has been a major cause of yield loss since it was first observed in 1885. Under a federal eradication program, surveys of PPD were conducted from 1929 to 1972, when the program was terminated. No surveys have been conducted in approximately 50 years; therefore, the current prevalence of PPD in the United States is unknown, especially in the Southeast, where damage was previously most severe. To ascertain the status of PPD, we surveyed orchards in Alabama, Florida, Georgia, and South Carolina from June to August 2020 and, except for South Carolina and northern Georgia, PPD was prevalent. Trees in 17 orchards were subjected to confirmation of X. fastidiosa using the AmplifyRP XRT+ for X. fastidiosa to corroborate our visual assessments; based on these tests, PPD incidence in the orchards ranged from 0 to 30.5%. Ancillary written surveys of relative PPD presence and prevalence were sent to fruit pathologists from universities in 20 states where PPD was historically reported. Only 35.0% of respondents reported that PPD either currently or recently occurred in their state and, of these, three reported PPD to be of significant concern. The results of the physical and written surveys indicate that PPD remains prevalent mainly in the southeastern region of the United States but, in other states where previously reported, it is either not present or has very low prevalence when compared with historical accounts of the disease.
Collapse
Affiliation(s)
- Kendall A Johnson
- Department of Plant Pathology, University of Georgia, 2105 Miller Plant Sciences Building, Athens, GA 30602
| | - Clive H Bock
- United States Department of Agriculture-Agricultural Research Service-Southeastern Fruit and Tree Nut Research Station, Byron, GA 31008
| | - Edgar L Vinson
- Department of Horticulture, Auburn University, Chilton Research and Extension Center, Clanton, AL 35045
| | - Phillip M Brannen
- Department of Plant Pathology, University of Georgia, 2105 Miller Plant Sciences Building, Athens, GA 30602
| |
Collapse
|
19
|
Gilioli G, Simonetto A, Colturato M, Bazarra N, Fernández JR, Naso MG, Donato B, Bosco D, Dongiovanni C, Maiorano A, Mosbach-Schulz O, Navas Cortés JA, Saponari M. An eco-epidemiological model supporting rational disease management of Xylella fastidiosa. An application to the outbreak in Apulia (Italy). Ecol Modell 2023. [DOI: 10.1016/j.ecolmodel.2022.110226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
20
|
Giménez-Romero A, Galván J, Montesinos M, Bauzà J, Godefroid M, Fereres A, Ramasco JJ, Matías MA, Moralejo E. Global predictions for the risk of establishment of Pierce's disease of grapevines. Commun Biol 2022; 5:1389. [PMID: 36539523 PMCID: PMC9768138 DOI: 10.1038/s42003-022-04358-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 12/09/2022] [Indexed: 12/24/2022] Open
Abstract
The vector-borne bacterium Xylella fastidiosa is responsible for Pierce's disease (PD), a lethal grapevine disease that originated in the Americas. The international plant trade is expanding the geographic range of this pathogen, posing a new threat to viticulture worldwide. To assess the potential incidence of PD, we have built a dynamic epidemiological model based on the response of 36 grapevine varieties to the pathogen in inoculation assays and on the vectors' distribution when this information is available. Key temperature-driven epidemiological processes, such as PD symptom development and recovery, are mechanistically modelled. Integrating into the model high-resolution spatiotemporal climatic data from 1981 onward and different infectivity (R0) scenarios, we show how the main wine-producing areas thrive mostly in non-risk, transient, or epidemic-risk zones with potentially low growth rates in PD incidence. Epidemic-risk zones with moderate to high growth rates are currently marginal outside the US. However, a global expansion of epidemic-risk zones coupled with small increments in the disease growth rate is projected for 2050. Our study globally downscales the risk of PD establishment while highlighting the importance of considering climate variability, vector distribution, and an invasive criterion as factors to obtain better PD risk maps.
Collapse
Affiliation(s)
- Alex Giménez-Romero
- grid.507629.f0000 0004 1768 3290Instituto de Física Interdisciplinar y Sistemas Complejos, (IFISC-UIB-CSIC), Campus UIB, 07122 Palma de Mallorca, Spain
| | - Javier Galván
- grid.507629.f0000 0004 1768 3290Instituto de Física Interdisciplinar y Sistemas Complejos, (IFISC-UIB-CSIC), Campus UIB, 07122 Palma de Mallorca, Spain
| | | | - Joan Bauzà
- grid.9563.90000 0001 1940 4767Departamento de Geografía, Universidad de las Islas Baleares, Campus UIB, 07122 Palma de Mallorca, Spain
| | - Martin Godefroid
- grid.4711.30000 0001 2183 4846Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, ICA-CSIC, 28006 Madrid, Spain
| | - Alberto Fereres
- grid.4711.30000 0001 2183 4846Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, ICA-CSIC, 28006 Madrid, Spain
| | - José J. Ramasco
- grid.507629.f0000 0004 1768 3290Instituto de Física Interdisciplinar y Sistemas Complejos, (IFISC-UIB-CSIC), Campus UIB, 07122 Palma de Mallorca, Spain
| | - Manuel A. Matías
- grid.507629.f0000 0004 1768 3290Instituto de Física Interdisciplinar y Sistemas Complejos, (IFISC-UIB-CSIC), Campus UIB, 07122 Palma de Mallorca, Spain
| | | |
Collapse
|
21
|
Stafford E, Kot M. Optimal reduced-mixing for an SIS infectious-disease model. JOURNAL OF BIOLOGICAL DYNAMICS 2022; 16:746-765. [PMID: 36415142 DOI: 10.1080/17513758.2022.2148764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
Which reduced-mixing strategy maximizes economic output during a disease outbreak? To answer this question, we formulate an optimal-control problem that maximizes the difference between revenue, due to healthy individuals, and medical costs, associated with infective individuals, for SIS disease dynamics. The control variable is the level of mixing in the population, which influences both revenue and the spread of the disease. Using Pontryagin's maximum principle, we find a closed-form solution for our problem. We explore an example of our problem with parameters for the transmission of Staphylococcus aureus in dairy cows, and we perform sensitivity analyses to determine how model parameters affect optimal strategies. We find that less mixing is preferable when the transmission rate is high, the per-capita recovery rate is low, or when the revenue parameter is much smaller than the cost parameter.
Collapse
Affiliation(s)
- Erin Stafford
- Department of Applied Mathematics, University of Washington, Seattle, WA, USA
| | - Mark Kot
- Department of Applied Mathematics, University of Washington, Seattle, WA, USA
| |
Collapse
|
22
|
Giménez-Romero À, Flaquer-Galmés R, Matías MA. Vector-borne diseases with nonstationary vector populations: The case of growing and decaying populations. Phys Rev E 2022; 106:054402. [PMID: 36559381 DOI: 10.1103/physreve.106.054402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 10/05/2022] [Indexed: 12/15/2022]
Abstract
Since the last century, deterministic compartmental models have emerged as powerful tools to predict and control epidemic outbreaks, in many cases helping to mitigate their impacts. A key quantity for these models is the so-called basic reproduction number, R_{0}, that measures the number of secondary infections produced by an initial infected individual in a fully susceptible population. Some methods have been developed to allow the direct computation of this quantity provided that some conditions are fulfilled, such that the model has a prepandemic disease-free equilibrium state. This condition is fulfilled only when the populations are stationary. In the case of vector-borne diseases, this implies that the vector birth and death rates need to be balanced. This is not fulfilled in many realistic cases in which the vector population grows or decreases. Here we develop a vector-borne epidemic model with growing and decaying vector populations that in the long term converge to an asymptotic stationary state, and study the conditions under which the standard methods to compute R_{0} work and discuss an alternative when they fail. We also show that growing vector populations produce a delay in the epidemic dynamics when compared to the case of the stationary vector population. Finally, we discuss the conditions under which the model can be reduced to the Susceptible, Infectious, and/or Recovered (SIR) model with fewer compartments and parameters, which helps in solving the problem of parameter unidentifiability of many vector-borne epidemic models.
Collapse
Affiliation(s)
- Àlex Giménez-Romero
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), 07122 Palma de Mallorca, Spain
| | - Rosa Flaquer-Galmés
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), 07122 Palma de Mallorca, Spain.,Grup de Física Estadística, Departament de Física. Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
| | - Manuel A Matías
- Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (UIB-CSIC), 07122 Palma de Mallorca, Spain
| |
Collapse
|
23
|
Vectors as Sentinels: Rising Temperatures Increase the Risk of Xylella fastidiosa Outbreaks. BIOLOGY 2022; 11:biology11091299. [PMID: 36138778 PMCID: PMC9495951 DOI: 10.3390/biology11091299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/17/2022]
Abstract
Global change is expected to modify the threat posed by pathogens to plants. However, little is known regarding how a changing climate will influence the epidemiology of generalist vector-borne diseases. We developed a high-throughput screening method to test for the presence of a deadly plant pathogen, Xylella fastidiosa, in its insect vectors. Then, using data from a four-year survey in climatically distinct areas of Corsica (France), we demonstrated a positive correlation between the proportion of vectors positive to X. fastidiosa and temperature. Notably, a higher prevalence corresponded with milder winters. Our projections up to 2100 indicate an increased risk of outbreaks. While the proportion of vectors that carry the pathogen should increase, the climate conditions will remain suitable for the bacterium and its main vector, with possible range shifts towards a higher elevation. Besides calling for research efforts to limit the incidence of plant diseases in the temperate zone, this work reveals that recent molecular technologies could and should be used for massive screening of pathogens in vectors to scale-up surveillance and management efforts.
Collapse
|
24
|
Ge Q, Zhu X, Cobine PA, De La Fuente L. The Copper-Binding Protein CutC Is Involved in Copper Homeostasis and Affects Virulence in the Xylem-Limited Pathogen Xylella fastidiosa. PHYTOPATHOLOGY 2022; 112:1620-1629. [PMID: 35196066 DOI: 10.1094/phyto-11-21-0488-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Copper (Cu) is an essential element that can be toxic if homeostasis is disrupted. Xylella fastidiosa, a xylem-limited plant pathogenic bacterium that causes disease in many economically important crops worldwide, has been exposed to Cu stress caused by wide application of Cu-containing antimicrobials used to control other diseases. However, X. fastidiosa Cu homeostasis mechanisms are still poorly understood. The potentially Cu-related protein CutC, which is involved in Cu tolerance in Escherichia coli and humans, has not been analyzed functionally in plant pathogenic bacteria. We demonstrate that recombinantly expressed X. fastidiosa CutC binds Cu and deletion of cutC gene (PD0586) in X. fastidiosa showed increased sensitivity to Cu-shock compared with wild type (WT) strain TemeculaL. When infecting plants in the greenhouse, cutC mutant showed decreased disease incidence and severity compared with WT but adding Cu exaggerated severity. Interestingly, the inoculation of cutC mutant caused reduced symptoms in the acropetal regions of plants. We hypothesize that X. fastidiosa cutC is involved in Cu homeostasis by binding Cu in cells, leading to Cu detoxification, which is crucial to withstand Cu-shock stress. Unveiling the role of cutC gene in X. fastidiosa facilitates further understanding of Cu homeostasis in bacterial pathogens.
Collapse
Affiliation(s)
- Qing Ge
- College of Enology, Northwest A&F University, Yangling, Shaanxi 712100, China
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A
| | - Xinyu Zhu
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, U.S.A
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, U.S.A
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A
| |
Collapse
|
25
|
Thidiazuron: New Trends and Future Perspectives to Fight Xylella fastidiosa in Olive Trees. Antibiotics (Basel) 2022; 11:antibiotics11070947. [PMID: 35884201 PMCID: PMC9312276 DOI: 10.3390/antibiotics11070947] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 11/25/2022] Open
Abstract
These days, most of our attention has been focused on the COVID-19 pandemic, and we have often neglected what is happening in the environment. For instance, the bacterium Xylella fastidiosa re-emerged as a plant pathogen of global importance in 2013 when it was first associated with an olive tree disease epidemic in Italy, called Olive Quick Decline Syndrome (OQDS), specifically caused by X. fastidiosa subspecies pauca ST53, which affects the Salento olive trees (Apulia, South-East Italy). This bacterium, transmitted by the insect Philaenus spumarius, is negatively reshaping the Salento landscape and has had a very high impact in the production of olives, leading to an increase of olive oil prices, thus new studies to curb this bacterium are urgently needed. Thidiazuron (TDZ), a diphenylurea (N-phenyl-1,2,3-thiadiazol-5-yl urea), has gained considerable attention in recent decades due to its efficient role in plant cell and tissue culture, being the most suitable growth regulator for rapid and effective plant production in vitro. Its biological activity against bacteria, fungi and biofilms has also been described, and the use of this low-cost compound to fight OQDS may be an intriguing idea.
Collapse
|
26
|
Abstract
AbstractThis review addresses ways to prepare for and to mitigate effects of biohazards on primary production of crops and livestock. These biohazards can be natural or intentional introductions of pathogens, and they can cause major economic damage to farmers, the agricultural industry, society, and international trade. Agroterrorism is the intentional introduction of animal or plant pathogens into agricultural production systems with the intention to cause socioeconomic harm and generate public fear. Although few acts of agroterrorism are reported, the threat of agroterrorism in Europe is real. New concerns about threats arise from the rapid advancements in biotechnology and emerging technologies. FORSA, an analytical framework for risk and vulnerability analysis, was used to review how to prepare for and mitigate the possible effects of natural or intentional biohazards in agricultural production. Analyzing the effects of a biohazard event involves multiple scientific disciplines. A comprehensive analysis of biohazards therefore requires a systems approach. The preparedness and ability to manage events are strengthened by bolstered farm biosecurity, increased monitoring and laboratory capacity, improved inter-agency communication and resource allocation. The focus of this review is on Europe, but the insights gained have worldwide applications. The analytical framework used here is compared to other frameworks. With climate change, Covid-19 and the war in Ukraine, the supply chains are challenged, and we foresee increasing food prices associated with social tensions. Our food supply chain becomes more fragile with more unknowns, thereby increasing the needs for risk and vulnerability analyses, of which FORSA is one example.
Collapse
|
27
|
Taguas I, Capitán JA, Nuño JC. Dropping mortality by increasing connectivity in plant epidemics. Phys Rev E 2022; 105:064301. [PMID: 35854574 DOI: 10.1103/physreve.105.064301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 04/24/2022] [Indexed: 06/15/2023]
Abstract
Pathogen introduction in plant communities can cause serious impacts and biodiversity losses that may take a long time to manage and restore. Effective control of epidemic spreading in the wild is a problem of paramount importance because of its implications in conservation and potential economic losses. Understanding the mechanisms that hinder pathogen propagation is, therefore, crucial. Usual modelization approaches in epidemic spreading are based in compartmentalized models, without keeping track of pathogen concentrations during spreading. In this contribution we present and fully analyze a dynamical model for plant epidemic spreading based on pathogen abundances. The model, which is defined on top of network substrates, is amenable to a deep mathematical analysis in the absence of a limit in the amount of pathogen a plant can tolerate before dying. In the presence of such death threshold, we observe that the fraction of dead plants peaks at intermediate values of network connectivity, and mortality decreases for large average degrees. We discuss the implications of our results as mechanisms to halt infection propagation.
Collapse
Affiliation(s)
- Ignacio Taguas
- Department of Applied Mathematics, Universidad Politécnica de Madrid, Avenida Juan de Herrera 6, E-28040 Madrid, Spain
| | - José A Capitán
- Department of Applied Mathematics, Universidad Politécnica de Madrid, Avenida Juan de Herrera 6, E-28040 Madrid, Spain
| | - Juan C Nuño
- Department of Applied Mathematics, Universidad Politécnica de Madrid, Avenida Juan de Herrera 6, E-28040 Madrid, Spain
| |
Collapse
|
28
|
Abstract
Lagoons are fragile marine ecosystems that are considerably affected by anthropogenic pollutants. We performed a spatiotemporal characterization of the microbiome of two Moroccan lagoons, Marchica and Oualidia, both classified as Ramsar sites, the former on the Mediterranean coast and the latter on the Atlantic coast. We investigated their microbial diversity and abundance using 16S rRNA amplicon- and shotgun-based metagenomics approaches during the summers of 2014 and 2015. The bacterial microbiome was composed primarily of Proteobacteria (25–53%, 29–29%), Cyanobacteria (34–12%, 11–0.53%), Bacteroidetes (24–16%, 23–43%), Actinobacteria (7–11%, 13–7%), and Verrucomicrobia (4–1%, 15–14%) in Marchica and Oualidia in 2014 and 2015, respectively. Interestingly, 48 strains were newly reported in lagoon ecosystems, while eight unknown viruses were detected in Mediterranean Marchica only. Statistical analysis showed higher microbial diversity in the Atlantic lagoon than in the Mediterranean lagoon and a robust relationship between alpha diversity and geographic sampling locations. This first-ever metagenomics study on Moroccan aquatic ecosystems enriched the national catalog of marine microorganisms. They will be investigated as candidates for bioindication properties, biomonitoring potential, biotechnology valorization, biodiversity protection, and lagoon health assessment.
Collapse
|
29
|
Johnson MA, Liu H, Bush E, Sharma P, Yang S, Mazloom R, Heath LS, Nita M, Li S, Vinatzer BA. Investigating plant disease outbreaks with long-read metagenomics: sensitive detection and highly resolved phylogenetic reconstruction applied to Xylella fastidiosa. Microb Genom 2022; 8. [PMID: 35584001 PMCID: PMC9465077 DOI: 10.1099/mgen.0.000822] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Early disease detection is a prerequisite for enacting effective interventions for disease control. Strains of the bacterial plant pathogen Xylella fastidiosa have recurrently spread to new crops in new countries causing devastating outbreaks. So far, investigation of outbreak strains and highly resolved phylogenetic reconstruction have required whole-genome sequencing of pure bacterial cultures, which are challenging to obtain due to the fastidious nature of X. fastidiosa. Here, we show that culture-independent metagenomic sequencing, using the Oxford Nanopore Technologies MinION long-read sequencer, can sensitively and specifically detect the causative agent of Pierce’s disease of grapevine, X. fastidiosa subspecies fastidiosa. Using a DNA sample from a grapevine in Virginia, USA, it was possible to obtain a metagenome-assembled genome (MAG) of sufficient quality for phylogenetic reconstruction with SNP resolution. The analysis placed the MAG in a clade with isolates from Georgia, USA, suggesting introduction of X. fastidiosa subspecies fastidiosa to Virginia from the south-eastern USA. This proof of concept study, thus, revealed that metagenomic sequencing can replace culture-dependent genome sequencing for reconstructing transmission routes of bacterial plant pathogens.
Collapse
Affiliation(s)
- Marcela A Johnson
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA.,Graduate Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA 24061, USA
| | - Haijie Liu
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Elizabeth Bush
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Parul Sharma
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA.,Graduate Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA 24061, USA
| | - Shu Yang
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Reza Mazloom
- Department of Computer Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Lenwood S Heath
- Department of Computer Science, Virginia Tech, Blacksburg, VA 24061, USA
| | - Mizuho Nita
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA.,AHS Jr. Agricultural Research and Extension Center, Virginia Tech, Winchester, VA 22602, USA
| | - Song Li
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Boris A Vinatzer
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| |
Collapse
|
30
|
Anguita-Maeso M, Haro C, Navas-Cortés JA, Landa BB. Primer Choice and Xylem-Microbiome-Extraction Method Are Important Determinants in Assessing Xylem Bacterial Community in Olive Trees. PLANTS (BASEL, SWITZERLAND) 2022; 11:1320. [PMID: 35631745 PMCID: PMC9144944 DOI: 10.3390/plants11101320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/09/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
Understanding the unique and unexplored microbial environment of xylem sap is starting to be of relevant importance for plant health, as it could include microbes that may protect plants against xylem-limited pathogens, such as Verticillium dahliae and Xylella fastidiosa. In this study, we evaluated the effects that the method for extracting the xylem bacterial communities, the plant age and the PCR primers may have on characterizing the xylem-bacterial-community composition by using an NGS approach. Xylem sap was extracted from xylem vessels by using a Scholander pressure chamber, or by macerating wood shavings that were obtained from xylem tissues by using branches from 10-year-old olive trees, or the entire canopy of 1-year-old olive plantlets. Additionally, we compared four different PCR-primer pairs that target 16S rRNA for their efficacy to avoid the coamplification of mitochondria and chloroplast 16S rRNA, as this represents an important drawback in metabarcoding studies. The highest amplifications in the mitochondria and chloroplast reads were obtained when using xylem woody chips with the PCR1-799F/1062R (76.05%) and PCR3-967F/1391R (99.96%) primer pairs. To the contrary, the PCR2-799F/1115R and PCR4-799F/1193R primer pairs showed the lowest mitochondria 16S rRNA amplification (<27.48%), no chloroplast sequences and the highest numbers of bacterial OTUs identified (i.e., 254 and 266, respectively). Interestingly, only 73 out of 172 and 46 out of 181 genera were shared between the xylem sap and woody chips after amplification with PCR2 or PCR4 primers, respectively, which indicates a strong bias of the bacterial-community description, depending on the primers used. Globally, the most abundant bacterial genera (>60% of reads) included Anoxybacillus, Cutibacterium, Pseudomonas, Spirosoma, Methylobacterium-Methylorubrum and Sphingomonas; however, their relative importance varied, depending on the matrix that was used for the DNA extraction and the primer pairs that were used, with the lowest effect due to plant age. These results will help to optimize the analysis of xylem-inhabiting bacteria, depending on whether whole xylematic tissue or xylem sap is used for the DNA extraction. More importantly, it will help to better understand the driving and modifying factors that shape the olive-xylem-bacterial-community composition.
Collapse
|
31
|
Cendoya M, Hubel A, Conesa D, Vicent A. Modeling the Spatial Distribution of Xylella fastidiosa: A Nonstationary Approach with Dispersal Barriers. PHYTOPATHOLOGY 2022; 112:1036-1045. [PMID: 34732079 DOI: 10.1094/phyto-05-21-0218-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Spatial species distribution models often assume isotropy and stationarity, implying that spatial dependence is direction-invariant and uniform throughout the study area. However, these assumptions are violated when dispersal barriers are present. Despite this, the issue of nonstationarity has been little explored in the context of plant health. The objective of this study was to evaluate the influence of barriers in the distribution of Xylella fastidiosa in the demarcated area in Alicante, Spain. Occurrence data from 2018 were analyzed through spatial Bayesian hierarchical models. The stationary model, illustrating a scenario without control interventions or geographical features, was compared with three nonstationary models: a model with mountains as physical barriers, and two models with a continuous and discontinuous perimeter barrier representing hypothetical control interventions. In the stationary model, the posterior mean of the spatial range, as the distance where two observations are uncorrelated, was 4,030 m 95% credible interval (2,907 to 5,564). This distance can be used to define the buffer zone in the demarcated area. The predicted probability of X. fastidiosa presence in the area outside the barrier was 0.46 with the stationary model, whereas it was reduced to 0.29 and 0.36 with the continuous and discontinuous barrier models, respectively. Differences between the discontinuous and continuous barrier models showed that breaks, where no control interventions were implemented, resulted in a higher predicted probability of X. fastidiosa presence in the areas with low sampling intensity. These results may help authorities prioritize the areas for surveillance and disease control.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
Collapse
Affiliation(s)
- Martina Cendoya
- Centre de Protecció Vegetal i Biotecnologia, Institut Valencià d'Investigacions Agràries, 46113 Moncada, Spain
| | - Ana Hubel
- Centre de Protecció Vegetal i Biotecnologia, Institut Valencià d'Investigacions Agràries, 46113 Moncada, Spain
| | - David Conesa
- Valencia Bayesian Research Group, Departament d'Estadística i Investigació Operativa, Universitat de València, 46100 València, Spain
| | - Antonio Vicent
- Centre de Protecció Vegetal i Biotecnologia, Institut Valencià d'Investigacions Agràries, 46113 Moncada, Spain
| |
Collapse
|
32
|
Prevention and control of OQDS (olive quick decline syndrome) outbreaks caused by Xylella fastidiosa. J Theor Biol 2022; 542:111118. [DOI: 10.1016/j.jtbi.2022.111118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/25/2022] [Accepted: 03/30/2022] [Indexed: 11/22/2022]
|
33
|
De Pascali M, Vergine M, Negro C, Greco D, Vita F, Sabella E, De Bellis L, Luvisi A. Xylella fastidiosa and Drought Stress in Olive Trees: A Complex Relationship Mediated by Soluble Sugars. BIOLOGY 2022; 11:biology11010112. [PMID: 35053110 PMCID: PMC8773346 DOI: 10.3390/biology11010112] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/02/2022] [Accepted: 01/07/2022] [Indexed: 12/19/2022]
Abstract
Simple Summary Carbohydrates play important roles in tolerance to both biotic and abiotic stressors. Xylella fastidiosa, the causal agent of “Olive Quick Decline Syndrome”, is a quarantine pathogen that induces drought stress in the host, aggravated by eventual water shortage, which is a frequent environmental condition in Mediterranean olive groves. At present, the resistance mechanisms shown by few resistant olive cultivars (e.g., cv Leccino) are not completely known; therefore, the aim of this research is to understand whether sugar metabolism is involved in the cross-talk mechanisms of biotic and abiotic responses. The results show that drought stress response induces effects beneficial to resistance of Xylella fastidiosa in cv Leccino. In the current context of global climate change, this study supports the importance of investigating the complex drought–disease interaction to detect resistance traits and thus find ways to counter the threat of this pathogen in the future. Abstract Xylella fastidiosa (Xf) subsp. pauca “De Donno” is the etiological agent of “Olive Quick Decline Syndrome” (OQDS) on olive trees (Olea europaea L.); the presence of the bacterium causes xylem vessel occlusions inducing a drought stress and the development of leaf scorch symptoms, which may be worsened by water shortage in summer. In order to evaluate how the two stress factors overlap each other, the carbohydrate content and the expression patterns of genes related to carbohydrate metabolism have been evaluated in two olive cvs trees (Cellina di Nardò, susceptible to Xf, and Leccino, resistant to Xf) reporting transcriptional dynamics elicited by Xf infection, drought, or combined stress (drought/Xf). In the Xf-susceptible Cellina di Nardò plants, Xf and its combination with drought significantly decrease total sugars compared to control (−27.0% and −25.7%, respectively). In contrast, the Xf-resistant Leccino plants show a more limited reduction in sugar content in Xf-positive conditions (−20.1%) and combined stresses (−11.1%). Furthermore, while the amount of glucose decreases significantly in stressed Cellina di Nardò plants (≈18%), an increase was observed in Leccino plants under drought/Xf combined stresses (+11.2%). An opposite behavior among cvs was also observed for sucrose, as an accumulation of the disaccharide was recorded in stressed Leccino plants (≈37%). The different response to combined stress by Xf-resistant plants was confirmed considering genes coding for the sucrose or monosaccharide transporter (OeSUT1, OeMST2), the cell wall or vacuolar invertase (OeINV-CW, OeINV-V), the granule-bound starch synthase I (OeGBSSI) and sucrose synthase (OeSUSY), with a higher expression than at least one single stress (e.g., ≈1-fold higher or more than Xf for OeMST2, OeINV-CW, OeINV-V, OeGBSSI). It is probable that the pathways involved in drought stress response induce positive effects useful for pathogen resistance in cv Leccino, confirming the importance of investigating the mechanisms of cross-talk of biotic and abiotic responses.
Collapse
Affiliation(s)
- Mariarosaria De Pascali
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
- Correspondence:
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| | - Davide Greco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| | - Federico Vita
- Department of Biology, University of Bari Aldo Moro, 70121 Bari, Italy;
| | - Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (M.D.P.); (C.N.); (D.G.); (E.S.); (L.D.B.); (A.L.)
| |
Collapse
|
34
|
Three Millennia of Vegetation, Land-Use, and Climate Change in SE Sicily. FORESTS 2022; 13:102. [PMID: 35909941 PMCID: PMC8944197 DOI: 10.3390/f13010102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/10/2022] [Indexed: 01/27/2023]
Abstract
This study presents the first Late Holocene marine pollen record (core ND2) from SE Sicily. It encompasses the last 3000 years and is one of the most detailed records of the south-central Mediterranean region in terms of time resolution. The combined approach of marine palynology and historical ecology, supported by independent palaeoclimate proxies, provides an integrated regional reconstruction of past vegetational dynamics in relation to rapid climatic fluctuations, historical socio-economic processes, and past land-use practices, offering new insights into the vegetation history of SE Sicily. Short-term variations of sparse tree cover in persistently open landscapes reflect rapid hydroclimatic changes and historical land-use practices. Four main phases of forest reduction are found in relation to the 2.8 ka BP event, including the Late Antique Little Ice Age, the Medieval Climate Anomaly, and the Little Ice Age, respectively. Forest recovery is recorded during the Hellenistic and Roman Republican Periods, the Early Middle Ages, and the last century. Agricultural and silvicultural practices, as well as stock-breeding activities, had a primary role in shaping the current vegetational landscape of SE Sicily.
Collapse
|
35
|
Rodrigues I, Ramos V, Benhadi-Marín J, Moreno A, Fereres A, Pereira JA, Baptista P. A novel molecular diagnostic method for the gut content analysis of Philaenus DNA. Sci Rep 2022; 12:492. [PMID: 35017549 PMCID: PMC8752687 DOI: 10.1038/s41598-021-04422-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 12/16/2021] [Indexed: 11/09/2022] Open
Abstract
Philaenus spumarius is a vector of Xylella fastidiosa, one of the most dangerous plants pathogenic bacteria worldwide. There is currently no control measure against this pathogen. Thus, the development of vector control strategies, like generalist predators, such as spiders, could be essential to limit the spread of this vector-borne pathogen. In this study, a polymerase chain reaction (PCR)-based approach was developed to principally detect DNA of P. spumarius in the spider's gut. Accordingly, 20 primer pairs, targeting the mitochondrial cytochrome oxidase I (COI) and cytochrome b (cytB) genes, were tested for specificity, sensitivity, and efficiency in detecting P. spumarius DNA. Overall, two primer sets, targeting COI gene (COI_Ph71F/COI_Ph941R) and the cytB gene (cytB_Ph85F/cytB_Ph635R), showed the highest specificity and sensitivity, being able to amplify 870 pb and 550 bp fragments, respectively, with P. spumarius DNA concentrations 100-fold lower than that of the DNA of non-target species. Among these two primer sets, the cytB_Ph85F/cytB_Ph635R was able to detect P. spumarius in the spider Xysticus acerbus, reaching 50% detection success 82 h after feeding. The feasibility of this primer set to detect predation of P. spumarius by spiders was confirmed in the field, where 20% of the collected spiders presented positive amplifications.
Collapse
Affiliation(s)
- Isabel Rodrigues
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal.,Departamento de Ingeniería Agrária, Universidad de Léon, Av. Portugal, n° 41, 24071, Léon, Spain
| | - Vítor Ramos
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal
| | - Jacinto Benhadi-Marín
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal
| | - Aránzazu Moreno
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas (ICA-CSIC), C/Serrano 115 dpdo, 28006, Madrid, Spain
| | - Alberto Fereres
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas (ICA-CSIC), C/Serrano 115 dpdo, 28006, Madrid, Spain
| | - José Alberto Pereira
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal
| | - Paula Baptista
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253, Bragança, Portugal.
| |
Collapse
|
36
|
Sertedakis M, Kotsaridis K, Tsakiri D, Mermigka G, Dominguez‐Ferreras A, Ntoukakis V, Sarris P. Expression of putative effectors of different Xylella fastidiosa strains triggers cell death-like responses in various Nicotiana model plants. MOLECULAR PLANT PATHOLOGY 2022; 23:148-156. [PMID: 34628713 PMCID: PMC8659589 DOI: 10.1111/mpp.13147] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 06/12/2023]
Abstract
The wide host range of Xylella fastidiosa (Xf) indicates the existence of yet uncharacterized virulence mechanisms that help pathogens to overcome host defences. Various bioinformatics tools combined with prediction of the functions of putative virulence proteins are valuable approaches to study microbial pathogenicity. We collected a number of putative effectors from three Xf strains belonging to different subspecies: Temecula-1 (subsp. fastidiosa), CoDiRO (subsp. pauca), and Ann-1 (subsp. sandyi). We designed an in planta Agrobacterium-based expression system that drives the expressed proteins to the cell apoplast, in order to investigate their ability to activate defence in Nicotiana model plants. Multiple Xf proteins differentially elicited cell death-like phenotypes in different Nicotiana species. These proteins are members of different enzymatic groups: (a) hydrolases/hydrolase inhibitors, (b) serine proteases, and (c) metal transferases. We also classified the Xf proteins according to their sequential and structural similarities via the I-TASSER online tool. Interestingly, we identified similar proteins that were able to differentially elicit cell death in different cultivars of the same species. Our findings provide a basis for further studies on the mechanisms that underlie both defence activation in Xf resistant hosts and pathogen adaptation in susceptible hosts.
Collapse
Affiliation(s)
| | - Konstantinos Kotsaridis
- Department of BiologyUniversity of CreteHeraklionGreece
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
| | - Dimitra Tsakiri
- Department of BiologyUniversity of CreteHeraklionGreece
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
| | - Glykeria Mermigka
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
| | | | | | - Panagiotis F. Sarris
- Department of BiologyUniversity of CreteHeraklionGreece
- Institute of Molecular Biology and BiotechnologyFoundation for Research and Technology‐HellasHeraklionGreece
- BiosciencesUniversity of ExeterExeterUK
| |
Collapse
|
37
|
Frem M, Fucilli V, Nigro F, El Moujabber M, Abou Kubaa R, La Notte P, Bozzo F, Choueiri E. The potential direct economic impact and private management costs of an invasive alien species: Xylella fastidiosa on Lebanese wine grapes. NEOBIOTA 2021. [DOI: 10.3897/neobiota.70.72280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since its outbreak in 2013 in Italy, the harmful bacterium Xylella fastidiosa has continued to spread throughout the Euro-Mediterranean basin and, more recently, in the Middle East region. Xylella fastidiosa subsp. fastidiosa is the causal agent of Pierce’s disease on grapevines. At present, this alien subspecies has not been reported in Lebanon but if this biological invader was to spread with no cost-effective and sustainable management, it would put Lebanese vineyards at a certain level of risk. In the absence of an Xylella fastidiosa subsp. fastidiosa outbreak, the gross revenue generated by Lebanese wine growers is estimated as close to US$22 million/year for an average period of 5 years (2015–2019). The potential quantitative economic impacts of an Xylella fastidiosa subsp. fastidiosa outbreak and particularly, the private control costs have not been assessed yet for this country as well as for others which Xylella fastidiosa may invade. Here, we have aimed to estimate the potential direct economic impact on growers’ livelihoods and provide the first estimate of the private management costs that a theoretical Xylella fastidiosa subsp. fastidiosa outbreak in Lebanon would involve. For this purpose, we used a Partial Budget approach at the farm gate. For the country as a whole, we estimated that a hypothetical full spread of Xylella fastidiosa subsp. fastidiosa on Lebanese wine grapes would lead to maximum potential gross revenue losses of almost US$ 11 million for an average recovery period of 4 years, to around US$ 82.44 million for an average grapevine life span period of 30 years in which infected plants are not replaced at all. The first yearly estimated additional management cost is US$853 per potentially infected hectare. For a recovery period of 4 years, the aggregate estimated additional cost would reach US$2374/ha, while the aggregate net change in profit would be US$-4046/ha. Furthermore, additional work will be needed to estimate the public costs of an Xylella fastidiosa subsp. fastidiosa outbreak in Lebanon. The observed costs in this study support the concerned policy makers and stakeholders to implement a set of reduction management options against Xylella fastidiosa subsp. fastidiosa at both national and wine growers’ levels. This re-emerging alien biota should not be neglected in this country. This understanding of the potential direct economic impact of Xylella fastidiosa subsp. fastidiosa and the private management costs can also benefit further larger-scale studies covering other potential infection areas and plant hosts.
Collapse
|
38
|
Moll L, Badosa E, Planas M, Feliu L, Montesinos E, Bonaterra A. Antimicrobial Peptides With Antibiofilm Activity Against Xylella fastidiosa. Front Microbiol 2021; 12:753874. [PMID: 34819923 PMCID: PMC8606745 DOI: 10.3389/fmicb.2021.753874] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/04/2021] [Indexed: 11/26/2022] Open
Abstract
Xylella fastidiosa is a plant pathogen that was recently introduced in Europe and is causing havoc to its agriculture. This Gram-negative bacterium invades the host xylem, multiplies, and forms biofilm occluding the vessels and killing its host. In spite of the great research effort, there is no method that effectively prevents or cures hosts from infections. The main control strategies up to now are eradication, vector control, and pathogen-free plant material. Antimicrobial peptides have arisen as promising candidates to combat this bacterium due to their broad spectrum of activity and low environmental impact. In this work, peptides previously reported in the literature and newly designed analogs were studied for its bactericidal and antibiofilm activity against X. fastidiosa. Also, their hemolytic activity and effect on tobacco leaves when infiltrated were determined. To assess the activity of peptides, the strain IVIA 5387.2 with moderate growth, able to produce biofilm and susceptible to antimicrobial peptides, was selected among six representative strains found in the Mediterranean area (DD1, CFBP 8173, Temecula, IVIA 5387.2, IVIA 5770, and IVIA 5901.2). Two interesting groups of peptides were identified with bactericidal and/or antibiofilm activity and low-moderate toxicity. The peptides 1036 and RIJK2 with dual (bactericidal–antibiofilm) activity against the pathogen and moderate toxicity stand out as the best candidates to control X. fastidiosa diseases. Nevertheless, peptides with only antibiofilm activity and low toxicity are also promising agents as they could prevent the occlusion of xylem vessels caused by the pathogen. The present work contributes to provide novel compounds with antimicrobial and antibiofilm activity that could lead to the development of new treatments against diseases caused by X. fastidiosa.
Collapse
Affiliation(s)
- Luís Moll
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Esther Badosa
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Marta Planas
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Lidia Feliu
- LIPPSO, Department of Chemistry, University of Girona, Girona, Spain
| | - Emilio Montesinos
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| | - Anna Bonaterra
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Girona, Spain
| |
Collapse
|
39
|
Pane C, Galieni A, Riefolo C, Nicastro N, Castrignanò A. Hyperspectral Reflectance Response of Wild Rocket ( Diplotaxis tenuifolia) Baby-Leaf to Bio-Based Disease Resistance Inducers Using a Linear Mixed Effect Model. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10122575. [PMID: 34961046 PMCID: PMC8707134 DOI: 10.3390/plants10122575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 06/14/2023]
Abstract
Baby leaf wild rocket cropping systems feeding the high convenience salad chain are prone to a set of disease agents that require management measures compatible with the sustainability-own features of the ready-to-eat food segment. In this light, bio-based disease resistance inducers able to elicit the plant's defense mechanism(s) against a wide-spectrum of pathogens are proposed as safe and effective remedies as alternatives to synthetic fungicides, to be, however, implemented under practical field applications. Hyperspectral-based proximal sensing was applied here to detect plant reflectance response to treatment of wild rocket beds with Trichoderma atroviride strain TA35, laminarin-based Vacciplant®, and Saccharomyces cerevisiae strain LAS117 cell wall extract-based Romeo®, compared to a local standard approach including synthetic fungicides (i.e., cyprodinil, fludioxonil, mandipropamid, and metalaxyl-m) and a not-treated control. Variability of the spectral information acquired in VIS-NIR-SWIR regions per treatment was explained by three principal components associated with foliar absorption of water, structural characteristics of the vegetation, and the ecophysiological plant status. Therefore, the following model-based statistical approach returned the interpretation of the inducers' performances at field scale consistent with their putative biological effects. The study stated that compost and laminarin-based treatments were the highest crop impacting ones, resulting in enhanced water intake and in stress-related pigment adjustment, respectively. Whereas plants under the conventional chemical management proved to be in better vigor and health status than the untreated control.
Collapse
Affiliation(s)
- Catello Pane
- Council for Agricultural Research and Economics (CREA), Research Centre for Vegetable and Ornamental Crops, Via Cavalleggeri 25, 84098 Pontecagnano Faiano, Italy;
| | - Angelica Galieni
- Council for Agricultural Research and Economics (CREA), Research Centre for Vegetable and Ornamental Crops, Via Salaria 1, 63030 Monsampolo del Tronto, Italy;
| | - Carmela Riefolo
- Council for Agricultural Research and Economics (CREA), Research Centre for Agriculture and Environment, Via Celso Ulpiani 5, 70125 Bari, Italy;
| | - Nicola Nicastro
- Council for Agricultural Research and Economics (CREA), Research Centre for Vegetable and Ornamental Crops, Via Cavalleggeri 25, 84098 Pontecagnano Faiano, Italy;
| | - Annamaria Castrignanò
- Department of Engineering and Geology (InGeo), “Gabriele D’Annunzio” University of Chieti-Pescara, Via dei Vestini 31, 66013 Chieti, Italy;
| |
Collapse
|
40
|
Csp1, a Cold Shock Protein Homolog in Xylella fastidiosa Influences Cell Attachment, Pili Formation, and Gene Expression. Microbiol Spectr 2021; 9:e0159121. [PMID: 34787465 PMCID: PMC8597638 DOI: 10.1128/spectrum.01591-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial cold shock-domain proteins are conserved nucleic acid binding chaperones that play important roles in stress adaptation and pathogenesis. Csp1 is a temperature-independent cold shock protein homolog in Xylella fastidiosa, a bacterial plant pathogen of grapevine and other economically important crops. Csp1 contributes to stress tolerance and virulence in X. fastidiosa. However, besides general single-stranded nucleic acid binding activity, little is known about the specific function(s) of Csp1. To further investigate the role(s) of Csp1, we compared phenotypic differences and transcriptome profiles between the wild type and a csp1 deletion mutant (Δcsp1). Csp1 contributes to attachment and long-term survival and influences gene expression. We observed reduced cell-to-cell attachment and reduced attachment to surfaces with the Δcsp1 strain compared to those with the wild type. Transmission electron microscopy imaging revealed that Δcsp1 was deficient in pili formation compared to the wild type and complemented strains. The Δcsp1 strain also showed reduced survival after long-term growth in vitro. Long-read nanopore transcriptome sequencing (RNA-Seq) analysis revealed changes in expression of several genes important for attachment and biofilm formation in Δcsp1 compared to that in the wild type. One gene of interest, pilA1, which encodes a type IV pili subunit protein, was upregulated in Δcsp1. Deleting pilA1 in X. fastidiosa strain Stag's Leap increased surface attachment in vitro and reduced virulence in grapevines. X. fastidiosa virulence depends on bacterial attachment to host tissue and movement within and between xylem vessels. Our results show that the impact of Csp1 on virulence may be due to changes in expression of attachment genes. IMPORTANCE Xylella fastidiosa is a major threat to the worldwide agriculture industry. Despite its global importance, many aspects of X. fastidiosa biology and pathogenicity are poorly understood. There are currently few effective solutions to suppress X. fastidiosa disease development or eliminate bacteria from infected plants. Recently, disease epidemics due to X. fastidiosa have greatly expanded, increasing the need for better disease prevention and control strategies. Our studies show a novel connection between cold shock protein Csp1 and pili abundance and attachment, which have not been reported for X. fastidiosa. Understanding how pathogenesis-related gene expression is regulated can aid in developing novel pathogen and disease control strategies. We also streamlined a bioinformatics protocol to process and analyze long-read nanopore bacterial RNA-Seq data, which will benefit the research community, particularly those working with non-model bacterial species.
Collapse
|
41
|
Zarco-Tejada PJ, Poblete T, Camino C, Gonzalez-Dugo V, Calderon R, Hornero A, Hernandez-Clemente R, Román-Écija M, Velasco-Amo MP, Landa BB, Beck PSA, Saponari M, Boscia D, Navas-Cortes JA. Divergent abiotic spectral pathways unravel pathogen stress signals across species. Nat Commun 2021; 12:6088. [PMID: 34667165 PMCID: PMC8526582 DOI: 10.1038/s41467-021-26335-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 10/01/2021] [Indexed: 11/30/2022] Open
Abstract
Plant pathogens pose increasing threats to global food security, causing yield losses that exceed 30% in food-deficit regions. Xylella fastidiosa (Xf) represents the major transboundary plant pest and one of the world's most damaging pathogens in terms of socioeconomic impact. Spectral screening methods are critical to detect non-visual symptoms of early infection and prevent spread. However, the subtle pathogen-induced physiological alterations that are spectrally detectable are entangled with the dynamics of abiotic stresses. Here, using airborne spectroscopy and thermal scanning of areas covering more than one million trees of different species, infections and water stress levels, we reveal the existence of divergent pathogen- and host-specific spectral pathways that can disentangle biotic-induced symptoms. We demonstrate that uncoupling this biotic-abiotic spectral dynamics diminishes the uncertainty in the Xf detection to below 6% across different hosts. Assessing these deviating pathways against another harmful vascular pathogen that produces analogous symptoms, Verticillium dahliae, the divergent routes remained pathogen- and host-specific, revealing detection accuracies exceeding 92% across pathosystems. These urgently needed hyperspectral methods advance early detection of devastating pathogens to reduce the billions in crop losses worldwide.
Collapse
Affiliation(s)
- P J Zarco-Tejada
- School of Agriculture and Food (SAF-FVAS) and Faculty of Engineering and Information Technology (IE-FEIT), University of Melbourne, Melbourne, VIC, Australia.
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain.
| | - T Poblete
- School of Agriculture and Food (SAF-FVAS) and Faculty of Engineering and Information Technology (IE-FEIT), University of Melbourne, Melbourne, VIC, Australia
| | - C Camino
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - V Gonzalez-Dugo
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
| | - R Calderon
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech, Cornell University, Geneva, NY, USA
| | - A Hornero
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
- Department of Geography, Swansea University, Swansea, SA2 8PP, UK
| | | | - M Román-Écija
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
| | - M P Velasco-Amo
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
| | - B B Landa
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
| | - P S A Beck
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - M Saponari
- CNR, Istituto per la Protezione Sostenibile delle Piante, Bari, Italy
| | - D Boscia
- CNR, Istituto per la Protezione Sostenibile delle Piante, Bari, Italy
| | - J A Navas-Cortes
- Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Avda. Menéndez Pidal s/n, 14004, Córdoba, Spain
| |
Collapse
|
42
|
Lázaro E, Sesé M, López-Quílez A, Conesa D, Dalmau V, Ferrer A, Vicent A. Tracking the outbreak: an optimized sequential adaptive strategy for Xylella fastidiosa delimiting surveys. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02572-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractThe EU plant health legislation enforces the implementation of intensive surveillance programs for quarantine pests. After an outbreak, surveys are implemented to delimit the extent of the infested zone and to manage disease control. Surveillance in agricultural and natural environments can be enhanced by increasing the survey efforts. Budget constraints often limit inspection and sampling intensities, thus making it necessary to adapt and optimize surveillance strategies. A sequential adaptive delimiting survey involving a three-phase and a two-phase design with increasing spatial resolution was developed and implemented for the Xylella fastidiosa demarcated area in Alicante, Spain. Inspection and sampling intensities were optimized using simulation-based methods. Sampling intensity thresholds were evaluated by quantifying their effect on the estimation of X. fastidiosa incidence. This strategy made it possible to sequence inspection and sampling taking into account increasing spatial resolutions, and to adapt the inspection and sampling intensities according to the information obtained in the previous, coarser, spatial resolution. The proposed strategy was able to efficiently delimit the extent of Xylella fastidiosa, while improving on the efficiency and maintaining the efficacy of the official survey campaign. From a methodological perspective, our approach provides new insights into alternative delimiting designs and new reference sampling intensity values.
Collapse
|
43
|
Use of meteorological data in biosecurity. Emerg Top Life Sci 2021; 4:497-511. [PMID: 32935835 PMCID: PMC7803344 DOI: 10.1042/etls20200078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/23/2020] [Accepted: 08/19/2020] [Indexed: 12/24/2022]
Abstract
Pests, pathogens and diseases cause some of the most widespread and damaging impacts worldwide — threatening lives and leading to severe disruption to economic, environmental and social systems. The overarching goal of biosecurity is to protect the health and security of plants and animals (including humans) and the wider environment from these threats. As nearly all living organisms and biological systems are sensitive to weather and climate, meteorological, ‘met’, data are used extensively in biosecurity. Typical applications include, (i) bioclimatic modelling to understand and predict organism distributions and responses, (ii) risk assessment to estimate the probability of events and horizon scan for future potential risks, and (iii) early warning systems to support outbreak management. Given the vast array of available met data types and sources, selecting which data is most effective for each of these applications can be challenging. Here we provide an overview of the different types of met data available and highlight their use in a wide range of biosecurity studies and applications. We argue that there are many synergies between meteorology and biosecurity, and these provide opportunities for more widespread integration and collaboration across the disciplines. To help communicate typical uses of meteorological data in biosecurity to a wide audience we have designed the ‘Meteorology for biosecurity’ infographic.
Collapse
|
44
|
Castro C, DiSalvo B, Roper MC. Xylella fastidiosa: A reemerging plant pathogen that threatens crops globally. PLoS Pathog 2021; 17:e1009813. [PMID: 34499674 PMCID: PMC8428566 DOI: 10.1371/journal.ppat.1009813] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Claudia Castro
- Department of Microbiology and Plant Pathology, University of California, Riverside, California, United States of America
| | - Biagio DiSalvo
- Department of Microbiology and Plant Pathology, University of California, Riverside, California, United States of America
| | - M. Caroline Roper
- Department of Microbiology and Plant Pathology, University of California, Riverside, California, United States of America
| |
Collapse
|
45
|
Hunter WB, Wintermantel WM. Optimizing Efficient RNAi-Mediated Control of Hemipteran Pests (Psyllids, Leafhoppers, Whitefly): Modified Pyrimidines in dsRNA Triggers. PLANTS 2021; 10:plants10091782. [PMID: 34579315 PMCID: PMC8472347 DOI: 10.3390/plants10091782] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/23/2021] [Accepted: 08/23/2021] [Indexed: 01/09/2023]
Abstract
The advantages from exogenously applied RNAi biopesticides have yet to be realized in through commercialization due to inconsistent activity of the dsRNA trigger, and the activity level of RNAi suppression. This has prompted research on improving delivery methods for applying exogenous dsRNA into plants and insects for the management of pests and pathogens. Another aspect to improve RNAi activity is the incorporation of modified 2′-F pyrimidine nucleotides into the dsRNA trigger. Modified dsRNA incorporating 32–55% of the 2′-F- nucleotides produced improved RNAi activity that increased insect mortality by 12–35% greater than non-modified dsRNA triggers of the same sequence. These results were repeatable across multiple Hemiptera: the Asian citrus psyllid (Diaphorina citri, Liviidae); whitefly (Bemisia tabaci, Aleyroididae); and the glassy-winged sharpshooter (Homalodisca vitripennis, Cicadellidae). Studies using siRNA with modified 2′-F- pyrimidines in mammalian cells show they improved resistance to degradation from nucleases, plus result in greater RNAi activity, due to increase concentrations and improved binding affinity to the mRNA target. Successful RNAi biopesticides of the future will be able to increase RNAi repeatability in the field, by incorporating modifications of the dsRNA, such as 2′-F- pyrimidines, that will improve delivery after applied to fruit trees or crop plants, with increased activity after ingestion by insects. Costs of RNA modification have decreased significantly over the past few years such that biopesticides can now compete on pricing with commercial chemical products.
Collapse
Affiliation(s)
- Wayne Brian Hunter
- U.S. Horticultural Research Laboratory, U.S. Department of Agriculture, Agriculture Research Service, Subtropical Insects Res., Fort Pierce, FL 34945, USA
- Correspondence:
| | - William M. Wintermantel
- U.S. Department of Agriculture, Agriculture Research Service, Crop Improvement and Protection Research, Salinas, CA 93905, USA;
| |
Collapse
|
46
|
Xylella fastidiosa in Olive: A Review of Control Attempts and Current Management. Microorganisms 2021; 9:microorganisms9081771. [PMID: 34442850 PMCID: PMC8397937 DOI: 10.3390/microorganisms9081771] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/09/2021] [Accepted: 08/14/2021] [Indexed: 11/17/2022] Open
Abstract
Since 2013, Xylella fastidiosa Wells et al. has been reported to infect several hosts and to be present in different areas of Europe. The main damage has been inflicted on the olive orchards of southern Apulia (Italy), where a severe disease associated with X. fastidiosa subspecies pauca strain De Donno has led to the death of millions of trees. This dramatic and continuously evolving situation has led to European and national (Italian and Spanish) measures being implemented to reduce the spread of the pathogen and the associated olive quick decline syndrome (OQDS). Research has been also carried out to find solutions to better and directly fight the bacterium and its main insect vector, Philaenus spumarius L. In the course of this frantic effort, several treatments based on chemical or biological substances have been tested, in addition to plant breeding techniques and integrated pest management approaches. This review aims to summarize the attempts made so far and describe the prospects for better management of this serious threat, which poses alarming questions for the future of olive cultivation in the Mediterranean basin and beyond.
Collapse
|
47
|
Picciotti U, Lahbib N, Sefa V, Porcelli F, Garganese F. Aphrophoridae Role in Xylella fastidiosa subsp. pauca ST53 Invasion in Southern Italy. Pathogens 2021; 10:1035. [PMID: 34451499 PMCID: PMC8399165 DOI: 10.3390/pathogens10081035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/11/2021] [Accepted: 08/12/2021] [Indexed: 12/03/2022] Open
Abstract
The Philaenus spumarius L. (Hemiptera Aphrophoridae) is a xylem-sap feeder vector that acquires Xylella fastidiosa subsp. pauca ST53 during feeding on infected plants. The bacterium is the plant pathogen responsible for olive quick decline syndrome that has decimated olive trees in Southern Italy. Damage originates mainly from the insect vector attitude that multiplies the pathogen potentialities propagating Xf in time and space. The principal action to manage insect-borne pathogens and to contain the disease spread consists in vector and transmission control. The analysis of an innovative and sustainable integrated pest management quantitative strategy that targets the vector and the infection by combining chemical and physical control means demonstrates that it is possible to stop the Xylella invasion. This review updates the available topics addressing vectors' identification, bionomics, infection management, and induced disease by Xylella invasion to discuss major available tools to mitigate the damage consequent to the disease.
Collapse
Affiliation(s)
- Ugo Picciotti
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, University of Bari Aldo Moro, 70126 Bari, Italy; (U.P.); (N.L.); (V.S.); (F.G.)
- Department of Marine Science and Applied Biology, Laboratory of Plant Pathology, University of Alicante, 03080 Alicante, Spain
| | - Nada Lahbib
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, University of Bari Aldo Moro, 70126 Bari, Italy; (U.P.); (N.L.); (V.S.); (F.G.)
- Faculty of Sciences of Tunis, University of Tunis El-Manar, Tunis 1068, Tunisia
- INRAT—National Institute of Agronomic Research of Tunisia, Laboratory of Plant Protection, Rue Hédi Karray, Ariana 2049, Tunisia
| | - Valdete Sefa
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, University of Bari Aldo Moro, 70126 Bari, Italy; (U.P.); (N.L.); (V.S.); (F.G.)
| | - Francesco Porcelli
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, University of Bari Aldo Moro, 70126 Bari, Italy; (U.P.); (N.L.); (V.S.); (F.G.)
- CIHEAM—Centre International de Hautes Etudes Agronomiques Méditerranéennes, Mediterranean Agronomic Institute of Bari, 70010 Valenzano, BA, Italy
| | - Francesca Garganese
- Dipartimento di Scienze del Suolo, della Pianta e degli Alimenti, University of Bari Aldo Moro, 70126 Bari, Italy; (U.P.); (N.L.); (V.S.); (F.G.)
| |
Collapse
|
48
|
Pavan S, Vergine M, Nicolì F, Sabella E, Aprile A, Negro C, Fanelli V, Savoia MA, Montilon V, Susca L, Delvento C, Lotti C, Nigro F, Montemurro C, Ricciardi L, De Bellis L, Luvisi A. Screening of Olive Biodiversity Defines Genotypes Potentially Resistant to Xylella fastidiosa. FRONTIERS IN PLANT SCIENCE 2021; 12:723879. [PMID: 34484283 PMCID: PMC8415753 DOI: 10.3389/fpls.2021.723879] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 07/23/2021] [Indexed: 06/12/2023]
Abstract
The recent outbreak of the Olive Quick Decline Syndrome (OQDS), caused by Xylella fastidiosa subsp. pauca (Xf), is dramatically altering ecosystem services in the peninsula of Salento (Apulia Region, southeastern Italy). Here we report the accomplishment of several exploratory missions in the Salento area, resulting in the identification of thirty paucisymptomatic or asymptomatic plants in olive orchards severely affected by the OQDS. The genetic profiles of such putatively resistant plants (PRPs), assessed by a selection of ten simple sequence repeat (SSR) markers, were compared with those of 141 Mediterranean cultivars. Most (23) PRPs formed a genetic cluster (K1) with 22 Italian cultivars, including 'Leccino' and 'FS17', previously reported as resistant to Xf. The remaining PRPs displayed relatedness with genetically differentiated germplasm, including a cluster of Tunisian cultivars. Markedly lower colonization levels were observed in PRPs of the cluster K1 with respect to control plants. Field evaluation of four cultivars related to PRPs allowed the definition of partial resistance in the genotypes 'Frantoio' and 'Nocellara Messinese'. Some of the PRPs identified in this study might be exploited in cultivation, or as parental clones of breeding programs. In addition, our results indicate the possibility to characterize resistance to Xf in cultivars genetically related to PRPs.
Collapse
Affiliation(s)
- Stefano Pavan
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Francesca Nicolì
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Alessio Aprile
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Valentina Fanelli
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | | | - Vito Montilon
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Leonardo Susca
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Chiara Delvento
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Concetta Lotti
- Department of Agriculture, Food, Natural Resources and Engineering, University of Foggia, Foggia, Italy
| | - Franco Nigro
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Cinzia Montemurro
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Luigi Ricciardi
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, Bari, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| |
Collapse
|
49
|
Redesigning Nature: Ruthenium Flavonoid Complexes with Antitumour, Antimicrobial and Cardioprotective Activities. Molecules 2021; 26:molecules26154544. [PMID: 34361697 PMCID: PMC8347471 DOI: 10.3390/molecules26154544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 11/17/2022] Open
Abstract
Flavonoids are a class of natural polyphenolic compounds sharing a common 2-phenyl-3,4-dihydro-2H-1-benzopyran (flavan) backbone. Typically known for their antioxidant activity, flavonoids are also being investigated regarding antitumour and antimicrobial properties. In this review, we report on the complexation of both natural and synthetic flavonoids with ruthenium as a strategy to modulate the biological activity. The ruthenoflavonoid complexes are divided into three subclasses, according to their most prominent bioactivity: antitumour, antimicrobial, and protection of the cardiovascular system. Whenever possible the activity of the ruthenoflavonoids is compared with that of commercial drugs for a critical assessment of the feasibility of using them in future clinical applications.
Collapse
|
50
|
Frem M, Santeramo FG, Lamonaca E, El Moujabber M, Choueiri E, La Notte P, Nigro F, Bozzo F, Fucilli V. Landscape restoration due to Xylella fastidiosa invasion in Italy: Assessing the hypothetical public’s preferences. NEOBIOTA 2021. [DOI: 10.3897/neobiota.66.67648] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since 2013, the olive landscapes have gradually degenerated due to the spread and establishment of Xylella fastidiosa subsp. pauca (hereafter Xf) in Apulia, southern Italy. From 2013 to 2019, a total of approximately 54,000 hectares of olive orchards in the south of this region have been seriously damaged, and their restoration will progressively regenerate the economic, social, cultural and environmental nonmarket benefits. Since there is a willingness to restore the affected landscape in the best interest of the local citizens, this research aims to predict their preference heterogeneity and willingness to pay (WTP) to improve this landscape and continue research and experimentation in relation to Olive Quick Decline Syndrome Disease by the bacterium. For this purpose, a choice experiment method is used. The social field survey includes a representative sample of 683 respondents in three major cities (Foggia, Bari and Lecce) of Apulia region. The results reveal that for the local citizens interviewed, the most appreciated olive landscape services are cultural heritage and aesthetic values. In addition, the findings revealed citizens’ positive appreciation of improving the damaged olive landscape, while respondents are not willing to pay a premium for research. The results show that the average value that Apulians are willing to pay for landscape restoration is about 5.7 million of € per year. Further, this research has implications for land use planners in the study area, which faces issues of harmful pathogen management and land revival.
Collapse
|