Biocontrol effect of Pythium oligandrum on artificial Fusarium culmorum infection during malting of wheat

AbstractCyclotides are cyclic peptides produced by plants. Due to their insecticidal properties, they are thought to be involved in host defense. Violets produce complex mixtures of cyclotides, that are characteristic for each species and variable in different environments. Herein, we utilized mass spectrometry (LC–MS, MALDI-MS), transcriptomics and biological assays to investigate the diversity, differences in cyclotide expression based on species and different environment, and antimicrobial activity of cyclotides found in violets from the Canary Islands. A wide range of different habitats can be found on these islands, from subtropical forests to dry volcano peaks at high altitudes. The islands are inhabited by the endemic Viola palmensis, V. cheiranthifolia, V. anagae and the common V. odorata. The number of cyclotides produced by a given species varied in plants from different environments. The highest diversity was noted in V. anagae which resides in subtropical forest and the lowest in V. cheiranthifolia from the Teide volcano. Transcriptome sequencing and LC–MS were used to identify 23 cyclotide sequences from V. anagae. Cyclotide extracts exhibited antifungal activities with the lowest minimal inhibitory concentrations noted for V. anagae (15.62 μg/ml against Fusarium culmorum). The analysis of the relative abundance of 30 selected cyclotides revealed patterns characteristic to both species and populations, which can be the result of genetic variability or environmental conditions in different habitats. The current study exemplifies how plants tailor their host defense peptides for various habitats, and the usefulness of cyclotides as markers for chemosystematics.

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Methods for Assessment of Resistance and Deoxynivalenol Production in Cereals Inoculated with Fusarium Culmorum

Cereal Research Communications ◽

10.1007/bf03543814 ◽

1997 ◽

Vol 25 (3) ◽

pp. 689-691

Author(s):

L. Sundheim ◽

W. Langseth ◽

O. Elen ◽

H. Skinnes ◽

W. Liu

Keyword(s):

Fusarium Culmorum

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The Potential of Rhizoctonia-Like Fungi for the Biological Protection of Cereals against Fungal Pathogens

Plants ◽

10.3390/plants10020349 ◽

2021 ◽

Vol 10 (2) ◽

pp. 349

Author(s):

Dominik Bleša ◽

Pavel Matušinský ◽

Romana Sedmíková ◽

Milan Baláž

Keyword(s):

Biological Control ◽

Fungal Pathogens ◽

Plant Pathogens ◽

Higher Plants ◽

Fusarium Culmorum ◽

Suppressive Effect ◽

Plant Production ◽

Shoot Biomass ◽

Organic Substrates

The use of biological control is becoming a common practice in plant production. One overlooked group of organisms potentially suitable for biological control are Rhizoctonia-like (Rh-like) fungi. Some of them are capable of forming endophytic associations with a large group of higher plants as well as mycorrhizal symbioses. Various benefits of endophytic associations were proved, including amelioration of devastating effects of pathogens such as Fusarium culmorum. The advantage of Rh-like endophytes over strictly biotrophic mycorrhizal organisms is the possibility of their cultivation on organic substrates, which makes their use more suitable for production. We focused on abilities of five Rh-like fungi isolated from orchid mycorrhizas, endophytic fungi Serendipita indica, Microdochium bolleyi and pathogenic Ceratobasidium cereale to inhibit the growth of pathogenic F. culmorum or Pyrenophora teres in vitro. We also analysed their suppressive effect on wheat infection by F. culmorum in a growth chamber, as well as an effect on barley under field conditions. Some of the Rh-like fungi affected the growth of plant pathogens in vitro, then the interaction with plants was tested. Beneficial effect was especially noted in the pot experiments, where wheat plants were negatively influenced by F. culmorum. Inoculation with S. indica caused higher dry shoot biomass in comparison to plants treated with fungicide. Prospective for future work are the effects of these endophytes on plant signalling pathways, factors affecting the level of colonization and surviving of infectious particles.

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Myco-Suppression Analysis of Soybean (Glycine max) Damping-Off Caused by Pythium aphanidermatum

Plants ◽

10.3390/plants10040788 ◽

2021 ◽

Vol 10 (4) ◽

pp. 788

Author(s):

Shaban R. M. Sayed ◽

Shaimaa A. M. Abdelmohsen ◽

Hani M. A. Abdelzaher ◽

Mohammed A. Elnaghy ◽

Ashraf A. Mostafa ◽

...

Keyword(s):

Glycine Max ◽

Biocontrol Agent ◽

Lateral Roots ◽

Dry Weight ◽

Pythium Aphanidermatum ◽

Damping Off ◽

Pythium Oligandrum ◽

Rdna Its ◽

Half Strength

The role of Pythium oligandrum as a biocontrol agent against Pythium aphanidermatum was investigated to avoid the harmful impacts of fungicides. Three isolates of P. oligandrum (MS15, MS19, and MS31) were assessed facing the plant pathogenic P. aphanidermatum the causal agent of Glycine max damping-off. The tested Pythium species were recognized according to their cultural and microscopic characterizations. The identification was confirmed through sequencing of rDNA-ITS regions including the 5.8 S rDNA. The biocontrol agent, P. oligandrum, isolates decreased the mycelial growth of the pathogenic P. aphanidermatum with 71.3%, 67.1%, and 68.7% through mycoparasitism on CMA plates. While the half-strength millipore sterilized filtrates of P. oligandrum isolates degrade the pathogenic mycelial linear growth by 34.1%, 32.5%, and 31.7%, and reduce the mycelial dry weight of the pathogenic P. aphanidermatum by 40.1%, 37.4%, and 36.8%, respectively. Scanning electron microscopy (SEM) of the most effective antagonistic P. oligandrum isolate (MS15) interaction showed coiling, haustorial parts of P. oligandrum to P. aphanidermatum hyphae. Furthermore, P. oligandrum isolates were proven to enhance the germination of Glycine max seedling to 93.3% in damping-off infection using agar pots and promote germination of up to 80% during soil pot assay. On the other hand, P. oligandrum isolates increase the shoot, root lengths, and the number of lateral roots.

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Evaluation of Spring and Winter Wheat Reaction to Fusarium culmorum and Fusarium avenaceum

Journal of Phytopathology ◽

10.1111/j.1439-0434.1997.tb00370.x ◽

1997 ◽

Vol 145 (2-3) ◽

pp. 99-103 ◽

Cited By ~ 6

Author(s):

S. Wojciechowski ◽

J. Chelkowski ◽

A. Ponitka ◽

A. Šlusarkiewicz-Jarzina

Keyword(s):

Winter Wheat ◽

Fusarium Culmorum ◽

Fusarium Avenaceum

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Transformations of Steroid Esters by Fusarium culmorum

Zeitschrift für Naturforschung C ◽

10.1515/znc-2006-11-1207 ◽

2006 ◽

Vol 61 (11-12) ◽

pp. 809-814 ◽

Cited By ~ 3

Author(s):

Alina Świzdor ◽

Teresa Kołek ◽

Anna Szpineter

Keyword(s):

Chlorine Atom ◽

Testosterone Propionate ◽

Fusarium Culmorum ◽

Quantitative Composition ◽

Main Metabolite ◽

17Β Estradiol ◽

Hydrolysis Of ◽

Regioselective Hydrolysis

Keywords The course of transformations of the pharmacological steroids: testosterone propionate, 4-chlorotestosterone acetate, 17β-estradiol diacetate and their parent alcohols in Fusarium culmorum AM282 culture was compared. The results show that this microorganism is capable of regioselective hydrolysis of ester bonds. Only 4-ene-3-oxo steroid esters were hydrolyzed at C-17. 17β-Estradiol diacetate underwent regioselective hydrolysis at C-3 and as a result, estrone - the main metabolite of estradiol - was absent in the reaction mixture. The alcohols resulting from the hydrolysis underwent oxidation at C-17 and hydroxylation. The same products (6β- and 15α-hydroxy derivatives) as from testosterone were formed by transformation of testosterone propionate, but the quantitative composition of the mixtures obtained after transformations of both substrates showed differences. The 15α-hydroxy derivatives were obtained from the ester in considerably higher yield than from the parent alcohol. The presence of the chlorine atom at C-4 markedly reduced 17β-saponification in 4-chloro- testosterone acetate. Only 3β,15α-dihydroxy-4α-chloro-5α-androstan-17-one (the main product of transformation of 4-chlorotestosterone) was identified in the reaction mixture. 6β- Hydroxy-4-chloroandrostenedione, which was formed from 4-chlorotestosterone, was |not detected in the extract obtained after conversion of its ester.

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Treatment with the Mycoparasite Pythium oligandrum Triggers Induction of Defense-Related Reactions in Tomato Roots When Challenged with Fusarium oxysporum f. sp. radicis-lycopersici

Phytopathology ◽

10.1094/phyto.1997.87.1.108 ◽

1997 ◽

Vol 87 (1) ◽

pp. 108-122 ◽

Cited By ~ 108

Author(s):

Nicole Benhamou ◽

Patrice Rey ◽

Mohamed Chérif ◽

John Hockenhull ◽

Yves Tirilly

Keyword(s):

Plant Defense ◽

Fusarium Oxysporum ◽

Host Cell ◽

Cell Walls ◽

Pythium Oligandrum ◽

Tomato Plants ◽

Host Cytoplasm ◽

Defense Reactions ◽

Tomato Roots ◽

Root Tissues

The influence exerted by the mycoparasite Pythium oligandrum in triggering plant defense reactions was investigated using an experimental system in which tomato plants were infected with the crown and root rot pathogen Fusarium oxysporum f. sp. radicis-lycopersici. To assess the antagonistic potential of P. oligandrum against F. oxysporum f. sp. radicis-lycopersici, the interaction between the two fungi was studied by scanning and transmission electron microscopy (SEM and TEM, respectively). SEM investigations of the interaction region between the fungi demonstrated that collapse and loss of turgor of F. oxysporum f. sp. radicis-lycopersici hyphae began soon after close contact was established with P. oligandrum. Ultrastructural observations confirmed that intimate contact between hyphae of P. oligandrum and cells of the pathogen resulted in a series of disturbances, including generalized disorganization of the host cytoplasm, retraction of the plasmalemma, and, finally, complete loss of the protoplasm. Cytochemical labeling of chitin with wheat germ agglutinin (WGA)/ovomucoid-gold complex showed that, except in the area of hyphal penetration, the chitin component of the host cell walls was structurally preserved at a time when the host cytoplasm had undergone complete disorganization. Interestingly, the same antagonistic process was observed in planta. The specific labeling patterns obtained with the exoglucanase-gold and WGA-ovomucoid-gold complexes confirmed that P. oligandrum successfully penetrated invading cells of the pathogen without causing substantial cell wall alterations, shown by the intense labeling of chitin. Cytological investigations of samples from P. oligandrum-inoculated tomato roots revealed that the fungus was able to colonize root tissues without inducing extensive cell damage. However, there was a novel finding concerning the structural alteration of the invading hyphae, evidenced by the frequent occurrence of empty fungal shells in root tissues. Pythium ingress in root tissues was associated with host metabolic changes, culminating in the elaboration of structural barriers at sites of potential fungal penetration. Striking differences in the extent of F. oxysporum f. sp. radicis-lycopersici colonization were observed between P. oligandrum-inoculated and control tomato plants. In control roots, the pathogen multiplied abundantly through much of the tissues, whereas in P. oligandrum-colonized roots pathogen growth was restricted to the outermost root tissues. This restricted pattern of pathogen colonization was accompanied by deposition of newly formed barriers beyond the infection sites. These host reactions appeared to be amplified compared to those seen in nonchallenged P. oligandrum-infected plants. Most hyphae of the pathogen that penetrated the epidermis exhibited considerable changes. Wall appositions contained large amounts of callose, in addition to be infiltrated with phenolic compounds. The labeling pattern obtained with gold-complexed laccase showed that phenolics were widely distributed in Fusarium-challenged P. oligandrum-inoculated tomato roots. Such compounds accumulated in the host cell walls and intercellular spaces. The wall-bound chitin component in Fusarium hyphae colonizing P. oligandrum-inoculated roots was preserved at a time when hyphae had undergone substantial degradation. These observations provide the first convincing evidence that P. oligandrum has the potential to induce plant defense reactions in addition to acting as a mycoparasite.

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