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Plant-Pathogen Interaction
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Plant-Pathogen Interaction

A special issue of Biology (ISSN 2079-7737). This special issue belongs to the section "Plant Science".

Deadline for manuscript submissions: closed (30 April 2021) | Viewed by 50577

Special Issue Editors

Dr. Maria Doroteia Campos

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Guest Editor
MED–Mediterranean Institute for Agriculture, Environment and Development & CHANGE–Global Change and Sustainability Institute, Institute for Advanced Studies and Research, Universidade de Évora, Évora, Portugal
Interests: plant protection; disease resistance; molecular diagnosis of plant pathogens
Special Issues, Collections and Topics in MDPI journals
Dr. Maria do Rosário Félix

E-Mail Website1 Website2
Guest Editor
MED–Mediterranean Institute for Agriculture, Environment and Development & CHANGE–Global Change and Sustainability Institute, Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Universidade de Évora, Évora, Portugal
Interests: plant pathology; pathogens and antagonists; molecular diagnostic tests; plant protection
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Plant pathogens cause severe loss in natural plant systems, as well as in terms of economics and production in the agriculture systems. While many biotic constraints are well known, and confronted with variable success, the occurrence of emerging pathogens and the progressive incidence of novel virulent strains, races or pathotypes is evident. Moreover, the practicability of some of the currently-available crop protection measures is questioned. Understanding how pathogens adopt an appropriate adaptive mechanism during plant infection, and the exploitation of the diversity of mechanisms that plants process to control the resistance/susceptibility to plant diseases, will aid in conserving nature and ecosystem services and is also of benefit for agriculture and forestry. The identification of regulatory components involved in the processes will be of major importance for a sustainable plant-disease management. Knowledge of plant–pathogen interactions could aid in the prevention of disease in plants, which would be beneficial to agricultural production and to global food security. For this Special Issue, we invite the submission of original research papers and reviews covering all aspects of plant–pathogen interactions, both in natural and agricultural systems.

Dr. Maria Doroteia Campos
Prof. Maria do Rosário Félix
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Biology is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Plant protection
  • Plant pathology
  • Plant disease resistance
  • Biotic stress
  • Plant innate immune response

Published Papers (10 papers)

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Editorial

Jump to: Research, Review

2 pages, 195 KiB  
Editorial
Plant-Pathogen Interaction
by Maria Doroteia Campos, Mariana Patanita, Carla Varanda, Patrick Materatski and Maria do Rosário Félix
Biology 2021, 10(5), 444; https://0-doi-org.brum.beds.ac.uk/10.3390/biology10050444 - 19 May 2021
Cited by 8 | Viewed by 2881
Abstract
Plant diseases result in severe losses to natural plant systems, and also cause problems for economics and production in agricultural systems [...] Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)

Research

Jump to: Editorial, Review

25 pages, 4855 KiB  
Article
Phylogenetic Analysis and Genetic Diversity of Colletotrichum falcatum Isolates Causing Sugarcane Red Rot Disease in Bangladesh
by Md Imam Hossain, Khairulmazmi Ahmad, Ganesan Vadamalai, Yasmeen Siddiqui, Norsazilawati Saad, Osumanu Haruna Ahmed, Erneeza Mohd Hata, Fariz Adzmi, Osamah Rashed, Muhammad Ziaur Rahman and Abdulaziz Bashir Kutawa
Biology 2021, 10(9), 862; https://0-doi-org.brum.beds.ac.uk/10.3390/biology10090862 - 03 Sep 2021
Cited by 10 | Viewed by 4755
Abstract
Colletotrichum falcatum Went causes red rot disease in sugarcane farming in the tropical and sub-tropical regions. This disease causes significant economic loss to the sugarcane production industry. Successful disease management strategies depend on understanding the evolutionary relationship between pathogens, genetic diversity, and population [...] Read more.
Colletotrichum falcatum Went causes red rot disease in sugarcane farming in the tropical and sub-tropical regions. This disease causes significant economic loss to the sugarcane production industry. Successful disease management strategies depend on understanding the evolutionary relationship between pathogens, genetic diversity, and population structure, particularly at the intra-specific level. Forty-one isolates of C. falcatum were collected from different sugarcane farms across Bangladesh for molecular identification, phylogeny and genetic diversity study. The four genes namely, ITS-rDNA, β-tubulin, Actin and GAPDH sequences were conducted. All the 41 C. falcatum isolates showed a 99–100% similarity index to the conserved gene sequences in the GenBank database. The phylogram of the four genes revealed that C. falcatum isolates of Bangladesh clustered in the same clade and no distinct geographical structuring were evident within the clade. The four gene sequences revealed that C. falcatum isolates from Bangladesh differed from other countries´ isolates because of nucleotides substitution at different loci. The genetic structure of C. falcatum isolates were determined using ISSR marker generated 404 polymorphic loci from 10 selected markers. The percentage of polymorphic loci was 99.01. The genetic variability at species level was slightly higher than at population level. Total mean gene diversity at the species level was 0.1732 whereas at population level it was 0.1521. The cluster analysis divided 41 isolates into four main genetic groups and the principal component analysis was consistent with cluster analysis. To the best of our knowledge, this is the first finding on characterizing C. falcatum isolates infesting sugarcane in Bangladesh. The results of this present study provide important baseline information vis a vis C. falcatum phylogeny analysis and genetic diversity study. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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23 pages, 1687 KiB  
Article
Endophytic Fungi as Potential Biological Control Agents against Grapevine Trunk Diseases in Alentejo Region
by Angela Billar de Almeida, Jonathan Concas, Maria Doroteia Campos, Patrick Materatski, Carla Varanda, Mariana Patanita, Sergio Murolo, Gianfranco Romanazzi and Maria do Rosário Félix
Biology 2020, 9(12), 420; https://0-doi-org.brum.beds.ac.uk/10.3390/biology9120420 - 26 Nov 2020
Cited by 28 | Viewed by 4293
Abstract
Grapevine trunk diseases (GTDs) are the most widespread fungal diseases, affecting grapevines in all the major growing regions of the world, and their complete eradication is still not possible. Aiming to search alternatives to avoid the spread and high incidence of these diseases, [...] Read more.
Grapevine trunk diseases (GTDs) are the most widespread fungal diseases, affecting grapevines in all the major growing regions of the world, and their complete eradication is still not possible. Aiming to search alternatives to avoid the spread and high incidence of these diseases, the present work intended to molecularly identify the grapevine endophytic community, the phytopathogenic fungi associated with GTDs in vineyards within the Alentejo region, and to test potential antagonist microorganisms as biological control candidates against GTDs-associated fungi. Grapevine endophytic community showed a wide variety of fungi in GTDs’ asymptomatic and symptomatic plants, nine of them previously described as GTDs-associated fungi. GTDs prevalent fungi identified in symptomatic plants were Diaporthe sp., Neofusicoccum sp., and H. viticola. Almost all these fungi were also detected in asymptomatic plants, which shows the importance of investigating the interactions of fungal communities and confirms the need for early diagnosis of these diseases. Direct inhibition antagonism tests were performed among identified endophytes and GTDs phytopathogenic fungi, and all the endophyte fungi showed potential as biocontrol agents. Our findings suggest that endophytes are promising candidates for their use in biological control due to their antagonistic activity against the mycelia growth of some GTDs-associated fungi. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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13 pages, 1527 KiB  
Article
Epigenetic Changes in Host Ribosomal DNA Promoter Induced by an Asymptomatic Plant Virus Infection
by Miryam Pérez-Cañamás, Elizabeth Hevia and Carmen Hernández
Biology 2020, 9(5), 91; https://0-doi-org.brum.beds.ac.uk/10.3390/biology9050091 - 28 Apr 2020
Cited by 6 | Viewed by 4034
Abstract
DNA cytosine methylation is one of the main epigenetic mechanisms in higher eukaryotes and is considered to play a key role in transcriptional gene silencing. In plants, cytosine methylation can occur in all sequence contexts (CG, CHG, and CHH), and its levels are [...] Read more.
DNA cytosine methylation is one of the main epigenetic mechanisms in higher eukaryotes and is considered to play a key role in transcriptional gene silencing. In plants, cytosine methylation can occur in all sequence contexts (CG, CHG, and CHH), and its levels are controlled by multiple pathways, including de novo methylation, maintenance methylation, and demethylation. Modulation of DNA methylation represents a potentially robust mechanism to adjust gene expression following exposure to different stresses. However, the potential involvement of epigenetics in plant-virus interactions has been scarcely explored, especially with regard to RNA viruses. Here, we studied the impact of a symptomless viral infection on the epigenetic status of the host genome. We focused our attention on the interaction between Nicotiana benthamiana and Pelargonium line pattern virus (PLPV, family Tombusviridae), and analyzed cytosine methylation in the repetitive genomic element corresponding to ribosomal DNA (rDNA). Through a combination of bisulfite sequencing and RT-qPCR, we obtained data showing that PLPV infection gives rise to a reduction in methylation at CG sites of the rDNA promoter. Such a reduction correlated with an increase and decrease, respectively, in the expression levels of some key demethylases and of MET1, the DNA methyltransferase responsible for the maintenance of CG methylation. Hypomethylation of rDNA promoter was associated with a five-fold augmentation of rRNA precursor levels. The PLPV protein p37, reported as a suppressor of post-transcriptional gene silencing, did not lead to the same effects when expressed alone and, thus, it is unlikely to act as suppressor of transcriptional gene silencing. Collectively, the results suggest that PLPV infection as a whole is able to modulate host transcriptional activity through changes in the cytosine methylation pattern arising from misregulation of methyltransferases/demethylases balance. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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19 pages, 5401 KiB  
Article
Isolation and Identification of Fusarium spp., the Causal Agents of Onion (Allium cepa) Basal Rot in Northeastern Israel
by Ben Kalman, Dekel Abraham, Shaul Graph, Rafael Perl-Treves, Yael Meller Harel and Ofir Degani
Biology 2020, 9(4), 69; https://0-doi-org.brum.beds.ac.uk/10.3390/biology9040069 - 02 Apr 2020
Cited by 35 | Viewed by 10723
Abstract
Over the past decade, there have been accumulating reports from farmers and field extension personnel on the increasing incidence and spread of onion (Allium cepa) bulb basal rot in northern Israel. The disease is caused mainly by Fusarium species. Rotting onion [...] Read more.
Over the past decade, there have been accumulating reports from farmers and field extension personnel on the increasing incidence and spread of onion (Allium cepa) bulb basal rot in northern Israel. The disease is caused mainly by Fusarium species. Rotting onion bulbs were sampled from fields in the Golan Heights in northeastern Israel during the summers of 2017 and 2018. Tissue from the sampled onion bulbs was used for the isolation and identification of the infecting fungal species using colony and microscopic morphology characterization. Final confirmation of the pathogens was performed with PCR amplification and sequencing using fungi-specific and Fusarium species-specific primers. Four Fusarium spp. isolates were identified in onion bulbs samples collected from the contaminated field: F. proliferatum, F. oxysporum f. sp. cepae, and two species less familiar as causative agents of this disease, F. acutatum and F. anthophilium. Phylogenetic analysis revealed that these species subdivided into two populations, a northern group isolated from white (Riverside cv.) onion bulbs, and a southern group isolated from red (565/505 cv.) bulbs. Pathogenicity tests conducted with seedlings and bulbs under moist conditions proved that all species could cause the disease symptoms, but with different degrees of virulence. Inoculating seeds with spore suspensions of the four species, in vitro, significantly reduced seedlings’ germination rate, hypocotyl elongation, and fresh biomass. Mature onion bulbs infected with the fungal isolates produced typical rot symptoms 14 days post-inoculation, and the fungus from each infected bulb was re-isolated and identified to satisfy Koch’s postulates. The onion bulb assay also reflected the degree of sensitivity of different onion cultivars to the disease. This work is the first confirmed report of the direct and primary cause of Fusarium onion basal rot disease in northeastern Israel. These findings are a necessary step towards uncovering the mycoflora of the diseased onion plants and developing a preventive program that would reduce the disease damage. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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16 pages, 1852 KiB  
Article
Effect of Tillage System and Cover Crop on Maize Mycorrhization and Presence of Magnaporthiopsis maydis
by Mariana Patanita, Maria Doroteia Campos, Maria do Rosário Félix, Mário Carvalho and Isabel Brito
Biology 2020, 9(3), 46; https://0-doi-org.brum.beds.ac.uk/10.3390/biology9030046 - 03 Mar 2020
Cited by 23 | Viewed by 3746
Abstract
The sustainability of agriculture requires the adoption of agricultural soil conservation practices with positive impacts on soil quality, which can promote beneficial soil microbiota like arbuscular mycorrhizal fungi (AMF) and its diversity. This study aims to assess the influence of the presence of [...] Read more.
The sustainability of agriculture requires the adoption of agricultural soil conservation practices with positive impacts on soil quality, which can promote beneficial soil microbiota like arbuscular mycorrhizal fungi (AMF) and its diversity. This study aims to assess the influence of the presence of intact extraradical mycelium as a preferential source of inoculum of the native AMF in order to guarantee a better colonization as well as its possible bioprotective effect against Magnaporthiopsis maydis. In order to vary the available extraradical mycelium, two experiments, with and without cover crop, were carried out, in which two tillage systems and two maize varieties were studied. The capitalization of the benefits, in terms of grain production and M. maydis presence, associated to the cover crop were only achieved with minimum tillage. Therefore, both cultural practices are necessary to reduce the fungus presence, coupling the effect of mycorrhization together with other benefits associated with the cover crop. Although in the absence of a cover crop and using conventional tillage, yields and lower levels of M. maydis are possibly achieved, this system is more dependent on the variety used, does not benefit from the advantages associated with the cover crop, is more expensive, and environmentally unsustainable. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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14 pages, 2000 KiB  
Article
Comparative Ergot Alkaloid Elaboration by Selected Plectenchymatic Mycelia of Claviceps purpurea through Sequential Cycles of Axenic Culture and Plant Parasitism
by Peter Mantle
Biology 2020, 9(3), 41; https://0-doi-org.brum.beds.ac.uk/10.3390/biology9030041 - 25 Feb 2020
Cited by 9 | Viewed by 4761
Abstract
Ergot alkaloids have an established place in plant pathology and toxicology. As pharmaceuticals, their sourcing is via natural or managed agricultural occurrence of sclerotia of Claviceps purpurea (Fr.) Tul. or through industrial fermentation processes with other Claviceps. The key factor for biosynthesis [...] Read more.
Ergot alkaloids have an established place in plant pathology and toxicology. As pharmaceuticals, their sourcing is via natural or managed agricultural occurrence of sclerotia of Claviceps purpurea (Fr.) Tul. or through industrial fermentation processes with other Claviceps. The key factor for biosynthesis is differentiation of a particular mycelial anatomy. Previous study of these fungi from two disparate English grass genera, Spartina and Phragmites, has shown that only mycelia expressing a plectenchymatic sclerotium-like anatomy in specific axenic culture conditions elaborated ergot alkaloids, and then only as far as lysergic acid. The present report describes sequential cycles of axenic and parasitic cultivation for wild isolates from Dactylis and Alopecurus with intervention of a single ascospore step. This confirms the homozygous character of C. purpurea and defines several potential experimental axenic and parasitic conditions within the species for comparing genomic aspects of partial or full biosynthesis of cyclic tri-peptide alkaloids. Whereas Alopecurus ergot isolates readily parasitized rye, use of Dactylis isolates as inoculum for rye ovaries failed to cause the usual sphacelial fructification but supported growth of exceptionally thin sclerotia, sometimes two in a floret, with low alkaloid content attributed to reduced medullary component. However, after two cycles of axenic and rye-parasitic cultivation, and consistent re-selection of the plectenchymatic character in axenic mycelia, typical growth of ergot sclerotia occurred on rye. Caution thus seems necessary in tests for putative host specificity in any taxonomic realignments within the classical concept of C. purpurea. A Dactylis ergot isolate was also uniquely shown to parasitise the plumule of germinating rye seeds confirming the susceptibility of apical tissues. A key biosynthetic feature of a mycelial glyceride oil, rich in ricinoleic acid, as a prelude to axenic and parasitic formation of ergot alkaloids by C. purpurea is emphasised. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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Review

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19 pages, 10842 KiB  
Review
Centenary of Soil and Air Borne Wheat Karnal Bunt Disease Research: A Review
by Mir Asif Iquebal, Pallavi Mishra, Ranjeet Maurya, Sarika Jaiswal, Anil Rai and Dinesh Kumar
Biology 2021, 10(11), 1152; https://doi.org/10.3390/biology10111152 - 09 Nov 2021
Cited by 6 | Viewed by 3856
Abstract
Karnal bunt (KB) of wheat (Triticum aestivum L.), known as partial bunt has its origin in Karnal, India and is caused by Tilletia indica (Ti). Its incidence had grown drastically since late 1960s from northwestern India to northern India in early 1970s. [...] Read more.
Karnal bunt (KB) of wheat (Triticum aestivum L.), known as partial bunt has its origin in Karnal, India and is caused by Tilletia indica (Ti). Its incidence had grown drastically since late 1960s from northwestern India to northern India in early 1970s. It is a seed, air and soil borne pathogen mainly affecting common wheat, durum wheat, triticale and other related species. The seeds become inedible, inviable and infertile with the precedence of trimethylamine secreted by teliospores in the infected seeds. Initially the causal pathogen was named Tilletia indica but was later renamed Neovossia indica. The black powdered smelly spores remain viable for years in soil, wheat straw and farmyard manure as primary sources of inoculum. The losses reported were as high as 40% in India and also the cumulative reduction of national farm income in USA was USD 5.3 billion due to KB. The present review utilizes information from literature of the past 100 years, since 1909, to provide a comprehensive and updated understanding of KB, its causal pathogen, biology, epidemiology, pathogenesis, etc. Next generation sequencing (NGS) is gaining popularity in revolutionizing KB genomics for understanding and improving agronomic traits like yield, disease tolerance and disease resistance. Genetic resistance is the best way to manage KB, which may be achieved through detection of genes/quantitative trait loci (QTLs). The genome-wide association studies can be applied to reveal the association mapping panel for understanding and obtaining the KB resistance locus on the wheat genome, which can be crossed with elite wheat cultivars globally for a diverse wheat breeding program. The review discusses the current NGS-based genomic studies, assembly, annotations, resistant QTLs, GWAS, technology landscape of diagnostics and management of KB. The compiled exhaustive information can be beneficial to the wheat breeders for better understanding of incidence of disease in endeavor of quality production of the crop. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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27 pages, 1221 KiB  
Review
Trends in Nanotechnology and Its Potentialities to Control Plant Pathogenic Fungi: A Review
by Abdulaziz Bashir Kutawa, Khairulmazmi Ahmad, Asgar Ali, Mohd Zobir Hussein, Mohd Aswad Abdul Wahab, Abdullahi Adamu, Abubakar A. Ismaila, Mahesh Tiran Gunasena, Muhammad Ziaur Rahman and Md Imam Hossain
Biology 2021, 10(9), 881; https://0-doi-org.brum.beds.ac.uk/10.3390/biology10090881 - 08 Sep 2021
Cited by 39 | Viewed by 5352
Abstract
Approximately 15–18% of crops losses occur as a result of animal pests, while weeds and microbial diseases cause 34 and 16% losses, respectively. Fungal pathogens cause about 70–80% losses in yield. The present strategies for plant disease control depend transcendently on agrochemicals that [...] Read more.
Approximately 15–18% of crops losses occur as a result of animal pests, while weeds and microbial diseases cause 34 and 16% losses, respectively. Fungal pathogens cause about 70–80% losses in yield. The present strategies for plant disease control depend transcendently on agrochemicals that cause negative effects on the environment and humans. Nanotechnology can help by reducing the negative impact of the fungicides, such as enhancing the solubility of low water-soluble fungicides, increasing the shelf-life, and reducing toxicity, in a sustainable and eco-friendly manner. Despite many advantages of the utilization of nanoparticles, very few nanoparticle-based products have so far been produced in commercial quantities for agricultural purposes. The shortage of commercial uses may be associated with many factors, for example, a lack of pest crop host systems usage and the insufficient number of field trials. In some areas, nanotechnology has been advanced, and the best way to be in touch with the advances in nanotechnology in agriculture is to understand the major aspect of the research and to address the scientific gaps in order to facilitate the development which can provide a rationale of different nanoproducts in commercial quantity. In this review, we, therefore, described the properties and synthesis of nanoparticles, their utilization for plant pathogenic fungal disease control (either in the form of (a) nanoparticles alone, that act as a protectant or (b) in the form of a nanocarrier for different fungicides), nano-formulations of agro-nanofungicides, Zataria multiflora, and ginger essential oils to control plant pathogenic fungi, as well as the biosafety and limitations of the nanoparticles applications. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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14 pages, 1207 KiB  
Review
Defense and Offense Strategies: The Role of Aspartic Proteases in Plant–Pathogen Interactions
by Laura Figueiredo, Rita B. Santos and Andreia Figueiredo
Biology 2021, 10(2), 75; https://0-doi-org.brum.beds.ac.uk/10.3390/biology10020075 - 21 Jan 2021
Cited by 26 | Viewed by 3789
Abstract
Plant aspartic proteases (APs; E.C.3.4.23) are a group of proteolytic enzymes widely distributed among different species characterized by the conserved sequence Asp-Gly-Thr at the active site. With a broad spectrum of biological roles, plant APs are suggested to undergo functional specialization and to [...] Read more.
Plant aspartic proteases (APs; E.C.3.4.23) are a group of proteolytic enzymes widely distributed among different species characterized by the conserved sequence Asp-Gly-Thr at the active site. With a broad spectrum of biological roles, plant APs are suggested to undergo functional specialization and to be crucial in developmental processes, such as in both biotic and abiotic stress responses. Over the last decade, an increasing number of publications highlighted the APs’ involvement in plant defense responses against a diversity of stresses. In contrast, few studies regarding pathogen-secreted APs and AP inhibitors have been published so far. In this review, we provide a comprehensive picture of aspartic proteases from plant and pathogenic origins, focusing on their relevance and participation in defense and offense strategies in plant–pathogen interactions. Full article
(This article belongs to the Special Issue Plant-Pathogen Interaction)
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