Impact of essential oils on the development of pathogens of the Fusarium genus and germination parameters of selected crops

Abstract Fungal pathogens can significantly reduce the potential yield of agricultural crops, especially cereals. One of the most dangerous are pathogens of the Fusarium genus. They contribute to the infestation of plants, reduction of yields, and contamination of agricultural crops with mycotoxins, which are harmful to human beings and animal health. The absence of active substances, the problem of pathogen resistance to fungicides, and the pressure of society to limit the use of chemical plant protection products are the most important issues in agriculture. This has resulted in research aimed at finding natural methods to control plant pathogens gaining importance. One of them is the use of essential oils. In laboratory experiments, clove essential oil and pine essential oil were used. The influence of different concentrations of the above-mentioned substances on the development of the mycelium of Fusarium species (F. equiseti, F. poae, F. culmorum, and F. avenaceum) was analyzed and the germination of wheat and maize seeds infected with the pathogens of the genus Fusarium was assessed. Clove oil significantly inhibited the growth of mycelium of the Fusarium species and reduced germination parameters than pine oil.

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Antimicrobial activity of essential oils on pathogenic fungi

Revista Agrogeoambiental ◽

10.18406/2316-1817v9n32017979 ◽

2017 ◽

Vol 9 (3) ◽

Author(s):

Daniele Aparecida do Couto ◽

Felipe Da Silva Dias ◽

Mírian Lobo Sáber

Keyword(s):

Essential Oils ◽

Eucalyptus Globulus ◽

Plant Pathogens ◽

Pathogenic Fungi ◽

Human Beings ◽

Cymbopogon Winterianus ◽

Callistemon Viminalis ◽

Pathogenic Agents ◽

Citronella Grass ◽

Mycelial Development

Since the induction of chemical defensives in agriculture, human beings have suffered from our own actions, caused by the indiscriminate and abusive use of those substances; therefore, researches have been motivated to look for alternative ways, aiming to use plant inputs to control pathogenic agents in agriculture. As the essential oils from the species Eucalyptus globulus (eucalyptus), Callistemon viminalis (weeping bottlebrush), Cymbopogon winterianus (citronella grass) and Tetradeniariparia (misty plume bush) have proved effectiveness and an immense applicability, this research studied the use of those essential oils, aiming the effectiveness against plant pathogens. The plants were collected from Universidade do Vale do Sapucaí, Pouso Alegre (MG). The fungi’s samples belong to the mycology collection from the institution and the tests were based on the mycelial development comparison of the control fungi on the dishes with essential oils. Notice that the inhibition caused by the oils over fungi’s mycelial developing and the analysis of the data have been made through Turkey’s statistic. From the data analyzed, it was possible to realize that the citronella’s grass essential oil was efficient to control the mycelial development of fungi analyzed, followed by, in order of efficiency, the eucalyptus oil, the weeping bottlebrush oil and the misty plume bush oil.

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Chemical Composition and Antifungal Effects of Vitex agnus-castus L. and Myrtus communis L. Plants

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha44210399 ◽

2016 ◽

Vol 44 (2) ◽

pp. 466-471 ◽

Cited By ~ 5

Author(s):

Melih YILAR ◽

Yusuf BAYAN ◽

Abdurrahman ONARAN

Keyword(s):

Chemical Composition ◽

Essential Oil ◽

Essential Oils ◽

Plant Pathogens ◽

Petri Dish ◽

Myrtus Communis ◽

Mycelium Growth ◽

Agnus Castus ◽

Petri Dishes

The purpose of this study was to assess the effectiveness of essential plant oils from Vitex agnus-castus L. (VAC) and Myrtus communis L. against the plant pathogens, Fusarium oxysporum f. sp. radicis-lycopersici (Sacc.) W.C. Synder & H.N. Hans, Rhizoctonia solani J.G. KÃ¼hn., Sclerotinia sclerotiorum (Lib.) de Bary and Verticillium dahliae Kleb., and to determine the chemical composition of the compounds in these essential oils. GC/MS analysis was identified 25 different compounds in VAC essential oil, while the main compounds were determined as Eucalyptol (17.75%), Î²-Caryophyllene (13.21%) and Spathulenol (10.41%). On the other hand, the essential oil of M. communis, consisted of 16 different compounds which were Eucalyptol (49.15%), Myrtenol (19.49%) and Î±-Pinene (8.38%) being its main compounds. An assessment of antifungal activity was performed under in vitro conditions. Plant pathogens were inoculated onto Petri dishes (60 mm) containing PDA medium (10 mL/Petri-1), and plant essential oils were applied at concentrations of 0.5, 1, 1.5, 2, 5 and 10 (Î¼L/Petri-1) into the 5 mm diameter wells opened on the Petri dish surface. After that, the Petri dishes incubated at 22Â±2 Â°C. The results of this study, the essential oil of M. communis, at a dose of 10 Î¼L/ Petri, inhibited the 100% mycelium growth of V. dahliae, S. sclerotiorum and R. solani. The highest dose of VAC essential oil was also 100% inhibited V. dahliae and S. sclerotiorum. The LC50 and LC90 values of M. communis and VAC essential oil calculated for V. dahliae, FORL, S. sclerotiorum and R. solani. This plant extracts were shown by in vitro conditions to be potential antifungal agents.

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Oregano essential oil vapour preventsPlasmopora viticolainfection in grapevine (Vitis Vinifera) by triggering autoimmune metabolic pathways

10.1101/602730 ◽

2019 ◽

Author(s):

Markus Rienth ◽

Julien Crovadore ◽

Sana Ghaffari ◽

François Lefort

Keyword(s):

Immune System ◽

Essential Oil ◽

Essential Oils ◽

Downy Mildew ◽

Innate Immune System ◽

Plant Protection ◽

Plant Protection Products ◽

Innate Immune ◽

Natural Plant ◽

First Time

AbstractThe reduction of synthetic fungicides in agriculture a major challenge in maintaining sustainable production, protecting the environment and consumers’ health. Downy mildew caused by the oomycete Plasmopora viticola is the major pathogen in viticulture worldwide and responsible for up to 60% of pesticide treatments. Alternatives to reduce fungicides are thus utterly needed to ensure sustainable vineyard-ecosystems, consumer health and public acceptance. Essential oils (EOs) are amongst the most promising natural plant protection alternatives and have shown their antibacterial, antiviral and antifungal properties on several agricultural crops. However, the efficiency of EOs highly depends on timing, application method and the molecular interactions between the host, the pathogen and EO. Despite proven EO efficiency, the underlying processes are still not understood and remain a black box. The objectives of the present study were: a) to evaluate whether a continuous fumigation of a particular EO can control downy mildew in order to circumvent the drawbacks of direct application, b) to decipher molecular mechanisms that could be triggered in the host and the pathogen by EO application and c) to try to differentiate whether essential oils directly repress the oomycete or act as plant resistance primers.A custom-made climatic chamber was used for a continuous fumigation of potted vines with different EOs during long-term experiments. The grapevine (Vitis vinifera) cv Chasselas was chosen in reason of its high susceptibility to Plasmopara viticola. Grapevine cuttings were infected with P. viticola. and subsequently exposed to continuous fumigation of different EOs at different concentrations, during 2 application time spans (24 hours and 10 days). Experiments were stopped when infection symptoms were clearly observed on the leaves of the control plants. Plant physiology (photosynthesis and growth rate parameters) were recorded and leaves were sampled at different time points for subsequent RNA extraction and transcriptomics analysis. Strikingly, the Oregano vulgare essential oil vapour treatment during 24h post-infection proved to be sufficient to reduce downy mildew development by 95%. Total RNA was extracted from leaves of 24h and 10d treatments and used for whole transcriptome shotgun sequencing (RNA-seq). Sequenced reads were then mapped onto the V. vinifera and P. viticola genomes. Less than 1% of reads could be mapped onto the P. viticola genome from treated samples, whereas up to 30 % reads from the controls mapped onto the P. viticola genome, thereby confirming the visual observation of P. viticola absence in the treated plants. On average, 80 % of reads could be mapped onto the V. vinifera genome for differential expression analysis, which yielded 4800 modulated genes. Transcriptomic data clearly showed that the treatment triggered the plant’s innate immune system with genes involved in salicylic, jasmonic acid and ethylene synthesis and signaling, activating Pathogenenesis-Related-proteins as well as phytoalexin synthesis.These results elucidate EO-host-pathogen interactions for the first time and indicate that the antifungal efficiency of EO is mainly due to the triggering of resistance pathways inside the host plants. This is of major importance for the production and research on biopesticides, plant stimulation products and for resistance-breeding strategiesAuthor SummaryThe reduction of synthetic plant protection products is a major concern of modern agriculture. The oomycetePlasmopora viticolawhich causes downy mildew in grapevine is amongst the most important grapevine pests and responsible for the dispersion of huge amounts of pesticides in vineyards. Among the evaluated alternatives to reduce or replace synthetic pesticides, plant volatile compounds could represent a sustainable solution. Some plant essential oils (EOs) have already shown antifungal capacities. However, their application is often difficult in terms of the right timing of treatment, degradation, bad rainfastness, mixability and phytotoxicity.The aim of the present work was to investigate whether the vapour phase, applied by a continuous fumigation of different EOs, might inhibit the development of downy mildew on grapevine, and in case of proven efficiency, to study the induced transcriptomic changes by RNA-sequencing in an attempt to elucidate the underlaying molecular interactions. Our results showed that the vapour phases ofO. vulgareandT. vulgariswere highly efficient against the pathogen. The study of differentially expressed genes indicated that the EO vapour triggered the main mechanisms of the plant’s innate immune system such as PTI (Pattern-Triggered Immunity) and ETI (Effector Triggered immunity).For the first time these results highlight the effects of EOs vapour on plant genes expression, which is very valuable information for the development of new natural plant protection products, as well as for breeding disease resistant cultivars.

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Screening of Antifungal and Antibacterial Activity of 90 Commercial Essential Oils against 10 Pathogens of Agronomical Importance

Foods ◽

10.3390/foods9101418 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1418

Author(s):

Caroline De Clerck ◽

Simon Dal Maso ◽

Olivier Parisi ◽

Frédéric Dresen ◽

Abdesselam Zhiri ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oils ◽

Plant Pathogens ◽

Plant Protection ◽

Fusarium Culmorum ◽

Plant Protection Products ◽

Colletotrichum Lindemuthianum ◽

Alternative Methods ◽

Organosulfur Compounds

Nowadays, the demand for a reduction of chemical pesticides use is growing. In parallel, the development of alternative methods to protect crops from pathogens and pests is also increasing. Essential oil (EO) properties against plant pathogens are well known, and they are recognized as having an interesting potential as alternative plant protection products. In this study, 90 commercially available essential oils have been screened in vitro for antifungal and antibacterial activity against 10 plant pathogens of agronomical importance. EOs have been tested at 500 and 1000 ppm, and measures have been made at three time points for fungi (24, 72 and 120 h of contact) and every two hours for 12 h for bacteria, using Elisa microplates. Among the EOs tested, the ones from Allium sativum, Corydothymus capitatus, Cinnamomum cassia, Cinnamomum zeylanicum, Cymbopogon citratus, Cymbopogon flexuosus, Eugenia caryophyllus, and Litsea citrata were particularly efficient and showed activity on a large panel of pathogens. Among the pathogens tested, Botrytis cinerea, Fusarium culmorum, and Fusarium graminearum were the most sensitive, while Colletotrichum lindemuthianum and Phytophthora infestans were the less sensitive. Some EOs, such as the ones from A. sativum, C. capitatus, C. cassia, C. zeylanicum, C. citratus, C. flexuosus, E. caryophyllus, and L. citrata, have a generalist effect, and are active on several pathogens (7 to 10). These oils are rich in phenols, phenylpropanoids, organosulfur compounds, and/or aldehydes. Others, such as EOs from Citrus sinensis, Melaleucacajputii, and Vanilla fragrans, seem more specific, and are only active on one to three pathogens. These oils are rich in terpenes and aldehydes.

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Composition, Mosquito Larvicidal, Biting Deterrent and Antifungal Activity of Essential Oils of Different Plant Parts of Cupressus arizonica var. glabra (‘Carolina Sapphire’)

Natural Product Communications ◽

10.1177/1934578x1300800232 ◽

2013 ◽

Vol 8 (2) ◽

pp. 1934578X1300800 ◽

Cited By ~ 4

Author(s):

Abbas Ali ◽

Nurhayat Tabanca ◽

Betul Demirci ◽

K. Husnu Can Baser ◽

Jane Ellis ◽

...

Keyword(s):

Gas Chromatography ◽

Antifungal Activity ◽

Essential Oil ◽

Essential Oils ◽

Plant Pathogens ◽

Gas Chromatography Mass Spectrometry ◽

Moderate Activity ◽

Female Cone ◽

Fungal Plant Pathogens ◽

Cupressus Arizonica

Essential oils obtained by hydrodistillation of female cones (FC), male cones (MC), needle-twigs (NT) and wood-bark (WB) of ‘Carolina Sapphire’ [Cupressus arizonica var glabra (Sudw.) Little] were analyzed simultaneously by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The main constituents of the investigated essential oils were as follows: FC: α-pinene 68.5% and myrcene 11.9%; MC: α-pinene 22.5%, epi- zonarene 9.9%, zonarene 6.9%, limonene 6.8% and cadina-3,5-diene 6.1%; NT: α-pinene 20.7%, epi-zonarene 10.4%, zonarene 7.6%, limonene 5.9% umbellulone 5.8% and cadina-3,5-diene 5.8%; WB: α-pinene 40.7%, limonene 3.2% and umbellulone 2.9%. Essential oils were evaluated for antifungal activity against the strawberry anthracnose causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. Only WB essential oil showed moderate activity when compared with the commercial antifungal standards. Carolina Sapphire essential oils exhibited biting deterrent activity at 10 pg/cm2 with Biting Deterrence Index (BDI) values of 0.64, 0.59, 0.65 and 0.72, for FC, MC, NT and WB, respectively, and were significantly lower (P≤0.05) than the synthetic insect repellent, DEET (N,N-diethyl-meta-toluamide), at 25 nmol/cm2 against Aedes aegypti. The biting deterrence of NT and WB oils at 100 μg/cm2 with BDI values of 1.04 and 1.01, respectively, were similar, whereas the activity of MC (BDI=0.88) and FC (BDI=0.62) essential oils was lower than DEET at 25 nmol/cm2. Essential oil from FC with LD50 of 33.7 ppm was most toxic against 1-day-old Ae. aegypti larvae at 24-h post treatment. Female cone essential oil was significantly more toxic than MC (LD50=53.6 ppm), NT (LD50=55.5 ppm) and WB (LD50=44.6 ppm) essential oils.

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Antifungal potential of cinnamon essential oils against Phytophthora colocasiae causing taro leaf blight

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-021-00238-3 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Zhang Hong ◽

Kalhoro Muhammad Talib ◽

Kalhoro Ghulam Mujtaba ◽

Hou Dabin ◽

Faqir Yahya ◽

...

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Plant Pathogens ◽

Chemical Constituents ◽

Leaf Blight ◽

Residual Effects ◽

Phytophthora Colocasiae ◽

Antifungal Potential ◽

Leaf Necrosis ◽

Taro Leaf Blight

Abstract Background Taro leaf blight, caused by a severely destructive oomycete fungus Phytophthora colocasiae, is responsible for threatening yield loss worldwide. The pathogen has the ability to germinate and spread rapidly to other plants during favorable conditions resulting in acute decline and even death, causing 100% crop loss. Farmers usually rely on highly toxic systemic fungicides to control the disease, which is effective, but residual effects and resistance of these agrochemicals is still a concern. Recently as returning to nature people tend to use chemical-free products, especially edible stuff produced in organic agriculture. Therefore, the use of bio-pesticides and phytochemicals is gaining special attention by scientists as they are ecofriendly non-hazardous, sustainable, and potent alternatives to control many virulent plant pathogens The present research was conducted to assess the antifungal potential of cinnamon essential oils against P. colocasiae. Materials and methods The essential oils from cinnamon bark were extracted using microwave-assisted hydrodistillation equipment, and then their chemical constituents were evaluated using ATR FTIR spectroscopy. The antifungal potential of essential oil was assessed against mycelium, sporangia, zoospore, leaf necrosis, and corms lesions under laboratory conditions at, 0.156, 0.312, 0.625, 1.25, 2.5, 5.0 mg/mL concentrations. Hymexazol was used as positive control and no essential oil as negative control, while each treatment have three replications and experiment repeated twice. Results The main component of oil was identified as cinnamaldehyde. The pathogen isolated from infected taro leaves was identified as P.colocasiae and then was used as a test fungus in the current study. Repeated experiments show maximum inhibition percentage of mycelial growth, zoospore germination, and sporulation of the fungus were observed at 0.625 mg/mL, whereas leaf necrosis was 100% inhibited at 1.25 mg/mL concentration. Conclusion This research can be a reference for easy, cost-effective and environment-friendly management and control of taro leaf blight with phytochemicals and plant essential oil derivatives. Graphic abstract

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Use of Competitive Filamentous Fungi as an Alternative Approach for Mycotoxin Risk Reduction in Staple Cereals: State of Art and Future Perspectives

Toxins ◽

10.3390/toxins11120701 ◽

2019 ◽

Vol 11 (12) ◽

pp. 701 ◽

Cited By ~ 6

Author(s):

Sabrina Sarrocco ◽

Antonio Mauro ◽

Paola Battilani

Keyword(s):

Filamentous Fungi ◽

Plant Pathogens ◽

Plant Protection ◽

Interference Competition ◽

Control Plant ◽

Plant Protection Products ◽

Plant Diseases ◽

Head Blight ◽

Mycotoxigenic Fungi ◽

Beneficial Fungi

Among plant fungal diseases, those affecting cereals represent a huge problem in terms of food security and safety. Cereals, such as maize and wheat, are very often targets of mycotoxigenic fungi. The limited availability of chemical plant protection products and physical methods to control mycotoxigenic fungi and to reduce food and feed mycotoxin contamination fosters alternative approaches, such as the use of beneficial fungi as an active ingredient of biological control products. Competitive interactions, including both exploitation and interference competition, between pathogenic and beneficial fungi, are generally recognized as mechanisms to control plant pathogens populations and to manage plant diseases. In the present review, two examples concerning the use of competitive beneficial filamentous fungi for the management of cereal diseases are discussed. The authors retrace the history of the well-established use of non-aflatoxigenic isolates of Aspergillus flavus to prevent aflatoxin contamination in maize and give an overview of the potential use of competitive beneficial filamentous fungi to manage Fusarium Head Blight on wheat and mitigate fusaria toxin contamination. Although important steps have been made towards the development of microorganisms as active ingredients of plant protection products, a reasoned revision of the registration rules is needed to significantly reduce the chemical based plant protection products in agriculture.

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Advances in screening approaches for the development of microbial bioprotectants to control plant diseases

10.19103/as.2021.0093.02 ◽

2021 ◽

pp. 33-86

Author(s):

Wagner Bettiol ◽

◽

Flávio Henrique Vasconcelos de Medeiros ◽

Josiane Barros Chiaramonte ◽

Rodrigo Mendes ◽

...

Keyword(s):

Plant Pathogens ◽

Plant Protection ◽

Control Plant ◽

Control Programme ◽

Plant Diseases ◽

Advantages And Disadvantages ◽

Fungal Plant Pathogens ◽

Soil Rhizosphere ◽

Selection Of ◽

Screening Approaches

The success of a biological control programme depends on the isolation and selection of antagonists. There is an enormous diversity of culturable microbial species in the soil, rhizosphere, phylloplane, spermosphere and carposphere, which can be used in the isolation and selection of antagonists. The structures of fungal plant pathogens concerned with survival and infection may also be sources of antagonists. Although non-culturable microorganisms and microbiome-based strategies have great potential for development as commercial products in disease control, more knowledge is needed to understand the mechanisms involved in interactions between plants and complex microbial communities. Methods of isolation and selection of the most commercially exploited groups of antagonists and their advantages and disadvantages are discussed in this chapter as well as those of non-traditional antagonists. Finally, possible strategies for engineering the soil and host microbiome to actively promote plant protection against pathogens are discussed.

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The invasive alien species Amorpha fruticosa in Bulgaria and its potential as economically prospective source of valuable essential oil

Pharmacia ◽

10.3897/pharmacia.67.e51334 ◽

2020 ◽

Vol 67 (4) ◽

pp. 357-362

Author(s):

Ekaterina Kozuharova ◽

Niko Benbassat ◽

Iliana Ionkova

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Alien Species ◽

Invasive Alien Species ◽

High Tolerance ◽

Habitat Conditions ◽

Potential Yield ◽

Amorpha Fruticosa ◽

Steam Extraction ◽

Number Of Individuals

The high tolerance of various habitat conditions and potent propagation ability of Amorpha fruticosa L. (Fabaceae) promote its aggressive invasive behaviour. The aim of this study is to evaluate 1) several populations of this plant by the potential yield of the fruit, 2) the approximate yield of the essential oils, and 3) composition of the essential oil. The potential yield of fruit is evaluated based on extrapolations of weight and number of fruits per infrutescence, number of infrutescences per plant and number of individuals per population. Steam extraction of the essential oil was performed and GS/MS analysis of the composition of the essential oil. The populations on our key plots are big enough for harvesting with fruit/infrutescence 152 ±15 (n = 20) and infrutescences/shrub 436 ±157 (n = 20). The yield is 0.83 ml/100g. We identified 22 components with major constituents caryophyllene (17.64%) α-guaiene (14.70%), naphthalene (6.75%), γ-muurolene + (5.98%).

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Antifungal and Phytotoxic Activities of Essential Oils: In Vitro Assays and Their Potential Use in Crop Protection

Agronomy ◽

10.3390/agronomy10060825 ◽

2020 ◽

Vol 10 (6) ◽

pp. 825

Author(s):

Imad El-Alam ◽

Robin Raveau ◽

Joël Fontaine ◽

Anthony Verdin ◽

Frédéric Laruelle ◽

...

Keyword(s):

Chemical Composition ◽

Essential Oils ◽

Direct Contact ◽

Plant Pathogens ◽

Biological Effects ◽

Crop Protection ◽

Control Plant ◽

In Vitro Assays ◽

Experimental Conditions ◽

Rye Grass

(1) Background: The use of natural products based on essential oils (EO) is nowadays arousing great interest as an alternative method to control plant pathogens and weeds. However, EO possess low bioavailability and are highly volatile, and their encapsulation in hydroxypropyl-ß-cyclodextrin (HP-β-CD) could be a means to enhance their stability and maintain their bioactivity. Thus, the current study aims at investigating, in the presence and the absence of HP-β-CD, the antifungal and phytotoxic activities of nine EO, distilled from plant species belonging to Alliaceae, Apiaceae, and Cupressaceae families, with considerations for their chemical composition. (2) Methods: EO antifungal activity was assessed by direct contact and volatility assays against Fusarium culmorum, a major phytopathogenic fungi, while phytotoxic effects were evaluated against lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), by seedling’s emergence and growth assays. (3) Results: These EO inhibit fungal growth in both direct contact and volatility assays, with half-maximal inhibitory concentrations (IC50) ranging from 0.01 to 4.2 g L−1, and from 0.08 up to 25.6 g L−1, respectively. Concerning phytotoxicity, these EO have shown great potential in inhibiting lettuce (IC50 ranging from 0.0008 up to 0.3 g L−1) and rye-grass (IC50 ranging from 0.01 to 0.8 g L−1) seedlings’ emergence and growth. However, the EO encapsulation in HP-β-CD has not shown a significant improvement in EO biological properties in our experimental conditions. (4) Conclusion: All tested EO present antifungal and phytotoxic activities, with diverse efficacy regarding their chemical composition, whilst no increase of their biological effects was observed with HP-β-CD.

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