Fungi as an Alternative to Agrochemicals to Control Plant Diseases

From a ‘farm to fork’ perspective, there are several phases in the production chain of fruits and vegetables in which undesired microbial contaminations can attack foodstuff. In managing these diseases, harvest is a crucial point for shifting the intervention criteria. While in preharvest, pest management consists of tailored agricultural practices, in postharvest, the contaminations are treated using specific (bio)technological approaches (physical, chemical, biological). Some issues connect the ‘pre’ and ‘post’, aligning some problems and possible solution. The colonisation of undesired microorganisms in preharvest can affect the postharvest quality, influencing crop production, yield and storage. Postharvest practices can ‘amplify’ the contamination, favouring microbial spread and provoking injures of the product, which can sustain microbial growth. In this context, microbial biocontrol is a biological strategy receiving increasing interest as sustainable innovation. Microbial-based biotools can find application both to control plant diseases and to reduce contaminations on the product, and therefore, can be considered biocontrol solutions in preharvest or in postharvest. Numerous microbial antagonists (fungi, yeasts and bacteria) can be used in the field and during storage, as reported by laboratory and industrial-scale studies. This review aims to examine the main microbial-based tools potentially representing sustainable bioprotective biotechnologies, focusing on the biotools that overtake the boundaries between pre- and postharvest applications protecting quality against microbial decay.

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The Use of Essential Oils from Thyme, Sage and Peppermint against Colletotrichum acutatum

Plants ◽

10.3390/plants10010114 ◽

2021 ◽

Vol 10 (1) ◽

pp. 114

Author(s):

Armina Morkeliūnė ◽

Neringa Rasiukevičiūtė ◽

Lina Šernaitė ◽

Alma Valiuškaitė

Keyword(s):

Essential Oils ◽

Fungal Pathogens ◽

Control Plant ◽

Antimicrobial Activities ◽

Plant Diseases ◽

Colletotrichum Acutatum ◽

Low Toxicity ◽

Colletotrichum Spp ◽

Biological Protection

The Colletotrichum spp. is a significant strawberry pathogen causing yield losses of up to 50%. The most common method to control plant diseases is through the use of chemical fungicides. The findings of plants antimicrobial activities, low toxicity, and biodegradability of essential oils (EO), make them suitable for biological protection against fungal pathogens. The aim is to evaluate the inhibition of Colletotrichum acutatum by thyme, sage, and peppermint EO in vitro on detached strawberry leaves and determine EO chemical composition. Our results revealed that the dominant compound of thyme was thymol 41.35%, peppermint: menthone 44.56%, sage: α,β-thujone 34.45%, and camphor: 20.46%. Thyme EO inhibited C. acutatum completely above 200 μL L−1 concentration in vitro. Peppermint and sage EO reduced mycelial growth of C. acutatum. In addition, in vitro, results are promising for biological control. The detached strawberry leaves experiments showed that disease reduction 4 days after inoculation was 15.8% at 1000 μL L−1 of peppermint EO and 5.3% at 800 μL L−1 of thyme compared with control. Our findings could potentially help to manage C. acutatum; however, the detached strawberry leaves assay showed that EO efficacy was relatively low on tested concentrations and should be increased.

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Pemberdayaan Kelompok Tani Hortikultura di Lahan Pasir melalui Pemanfaatan Kayambang (Salvinia molesta) sebagai Trichokompos

PengabdianMu Jurnal Ilmiah Pengabdian kepada Masyarakat ◽

10.33084/pengabdianmu.v6i4.1846 ◽

2021 ◽

Vol 6 (4) ◽

pp. 369-375

Author(s):

Rahmawati Budi Mulyani ◽

Lilies Supriati ◽

Melhanah Melhanah ◽

Susi Kresnatita

Keyword(s):

Control Plant ◽

Biological Agents ◽

Plant Diseases ◽

Organic Fertilizers ◽

Mentoring Program ◽

Salvinia Molesta ◽

Horticultural Crop ◽

Self Help ◽

Trichoderma Sp ◽

Farmer Groups

Lebak swamp weeds such as Kayambang (Salvinia molesta) grow abundantly. They can be used as compost, which effectively improves soil fertility, increasing nutrients N, P, and P K quickly and environmentally friendly. The effectiveness of compost fertilizer needs to be increased by adding indigenous microbes as decomposers and biological agents to control plant diseases. The activities carried out to empower horticultural farmer groups on sandy land in Tanjung Pinang Village, Palangka Raya are through socialization, training in composting with three types of antagonist fungus Trichoderma sp. (Trichocompost), facilitate the procurement of weed chopping machines, assist farmers in horticultural crop cultivation, and increase farmers' independence in self-supporting organic fertilizers. The use of Kayambang as Trichocompost with microbial decomposers and indigenous biological agents is new knowledge for partner farmers. The application of Trichocompost on the demonstration plots shows that eggplant plant growth and yields are excellent, meaning that Trichocompost can improve the fertility of sandy soils. Farmers participating in the training stated that the use of Trichocompost could reduce farming costs because it can substitute for manure that has been used by farmers and can meet the self-help needs of organic fertilizers. Participants wanted an advanced mentoring program because the farmers had not yet mastered the isolation or propagation of biological agents and decomposer microbes.

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Clonostachys rosea to control plant diseases

10.19103/as.2021.0093.14 ◽

2021 ◽

pp. 429-472

Author(s):

Dan Funck Jensen ◽

◽

Mukesh Dubey ◽

Birgit Jensen ◽

Magnus Karlsson ◽

...

Keyword(s):

Biological Control ◽

Plant Protection ◽

Control Plant ◽

Plant Diseases ◽

Bumble Bees ◽

Key Factors ◽

Clonostachys Rosea ◽

Protection Strategies ◽

Rhizosphere Competence ◽

Potential Use

The fungus Clonostachys rosea was recognized as an aggressive parasite on other fungi already in the late 1950s. Research into its potential use in biological control of plant diseases soon followed. Today, there are several commercial products based on C. rosea available for biocontrol applications worldwide. Although its mycoparasitic ability has attracted a lot of interest, C. rosea is now viewed as an ecological generalist whose lifestyle also includes plant endophytism, rhizosphere competence and polyphagous ability. Protocols for producing high amounts of C. rosea spores are available for both solid state and liquid fermentation. Low temperature and low moisture content are key factors that influence the shelf life of C. rosea propagules. Products based on C. rosea can be delivered to flowers using bumble bees, applied by spraying or as seed dressing or by incorporation into the soil. Clonostachys rosea is today an established factor in sustainable plant protection strategies.

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How to Control Plant Diseases in Home and Garden

Mycologia ◽

10.2307/3756788 ◽

1967 ◽

Vol 59 (3) ◽

pp. 561

Author(s):

Robert D. Raabe ◽

Malcolm C. Shurtleff

Keyword(s):

Control Plant ◽

Plant Diseases

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Actinomycetes, promising tools to control plant diseases and to promote plant growth

Phytoprotection ◽

10.7202/706219ar ◽

2005 ◽

Vol 82 (3) ◽

pp. 85-102 ◽

Cited By ~ 126

Author(s):

C.L. Doumbou ◽

M.K. Hamby Salove ◽

D.L. Crawford ◽

C. Beaulieu

Keyword(s):

Plant Growth ◽

Plant Pathogens ◽

Soil Microbial Biomass ◽

Extracellular Enzymes ◽

Control Plant ◽

Plant Diseases ◽

Soil Microbial ◽

Plant Growth Promoting ◽

Promote Plant Growth ◽

Growth Promoting

Actinomycetes represent a high proportion of the soil microbial biomass and have the capacity to produce a wide variety of antibiotics and of extracellular enzymes. Several strains of actinomycetes have been found to protect plants against plant diseases. This review focuses on the potential of actinomycetes as (a) source of agroactive compounds, (b) plant growth promoting organisms, and (c) biocontrol tools of plant diseases. This review also addresses examples of biological control of fungal and bacterial plant pathogens by actinomycetes species which have already reached the market or are likely to be exploited commercially within the next few years.

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Morphological and molecular based identification of Antifungal bacillus licheniformis

Mongolian Journal of Agricultural Sciences ◽

10.5564/mjas.v17i1.724 ◽

2017 ◽

Vol 17 (1) ◽

pp. 31-35

Author(s):

B Oyuntogtokh ◽

M Byambasuren

Keyword(s):

Bacillus Licheniformis ◽

Fungal Pathogens ◽

Crop Production ◽

Plant Pathogens ◽

Control Plant ◽

Plant Diseases ◽

Bacillus Species ◽

Bacterial Strains ◽

Fusarium Spp ◽

Bacterial Cultures

At present, plant diseases caused by soil borne plant pathogens have major constraints on crop production. Which include genera Fusarium spp, Phytophtora spp, Sclerotinia and Altenaria. Due to this reason, chemical fungicides are routinely used to control plant disease, which is also true in Mongolian case. However, use of these chemicals has caused various problems including environmental pollution with consequence of toxicity to human health also resistance of some pathogens to these fungicides are present. Fortunately, an alternative method to reduce the effect of these plant pathogens is the use of antagonist microorganisms. Therefore, some species of the genus Bacillus are recognized as one of the most effective biological control agent.Our research was focused to isolate Bacillus licheniformis, with antifungal potential, from indigenous sources. In the current study, 28 bacterial cultures were isolated from soil and fermented mare’s milk also named as koumiss. Isolated bacterial cultures were identified according to simplified key for the tentative identification of typical strain of Bacillus species. As a result 8 strains were positive and further screened for antifungal activity against Fusarium spp and Alternaria solani. Out of these 8 strains 5 strains are selected based on their high effectiveness against fungal pathogens and for further confirmation Polymerase Chain reaction run for effective bacterial strains using specific primers B.Lich-f and B.Lich-r.

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Optimizing Plant Disease Management in Agricultural Ecosystems Through Rational In-Crop Diversification

Frontiers in Plant Science ◽

10.3389/fpls.2021.767209 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yan-Ping Wang ◽

Zhe-Chao Pan ◽

Li-Na Yang ◽

Jeremy J. Burdon ◽

Hanna Friberg ◽

...

Keyword(s):

Late Blight ◽

Host Resistance ◽

Control Plant ◽

Late Blight Resistance ◽

Plant Diseases ◽

Crop Diversification ◽

Agricultural Ecosystems ◽

Potato Varieties ◽

Plant Disease Management ◽

Disease Epidemics

Biodiversity plays multifaceted roles in societal development and ecological sustainability. In agricultural ecosystems, using biodiversity to mitigate plant diseases has received renewed attention in recent years but our knowledge of the best ways of using biodiversity to control plant diseases is still incomplete. In term of in-crop diversification, it is not clear how genetic diversity per se in host populations interacts with identifiable resistance and other functional traits of component genotypes to mitigate disease epidemics and what is the best way of structuring mixture populations. In this study, we created a series of host populations by mixing different numbers of potato varieties showing different late blight resistance levels in different proportions. The amount of naturally occurring late blight disease in the mixture populations was recorded weekly during the potato growing seasons. The percentage of disease reduction (PDR) in the mixture populations was calculated by comparing their observed late blight levels relative to that expected when they were planted in pure stands. We found that PDR in the mixtures increased as the number of varieties and the difference in host resistance (DHR) between the component varieties increased. However, the level of host resistance in the potato varieties had little impact on PDR. In mixtures involving two varieties, the optimum proportion of component varieties for the best PDR depended on their DHR, with an increasing skewness to one of the component varieties as the DHR between the component varieties increased. These results indicate that mixing crop varieties can significantly reduce disease epidemics in the field. To achieve the best disease mitigation, growers should include as many varieties as possible in mixtures or, if only two component mixtures are possible, increase DHR among the component varieties.

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Protein Elicitor EsxA Induces Resistance to Seedling Blight and PR Genes Differential Transcription in Rice

Rice ◽

10.1186/s12284-021-00532-6 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Wen Qing Yu ◽

Peng Li ◽

Feng Chao Yan ◽

Gui Ping Zheng ◽

Wen Zhi Liu ◽

...

Keyword(s):

Plant Growth ◽

Germination Rate ◽

Control Plant ◽

Plant Diseases ◽

Systemic Resistance ◽

Seedling Blight ◽

Pr Genes ◽

Protein Elicitor ◽

Animal Pathogens ◽

Differential Transcription

AbstractProtein elicitors can induce plant systemic resistance to pathogens. In an earlier study, we cloned an EsxA gene from the plant growth-promoting rhizobacterium Paenibacillus terrae NK3-4 and expressed it in Pichia pastoris. In addition to being important for the pathogenicity of animal pathogens, EsxA can also induce an immune response in animals. While, we found the exogenously expressed EsxA has the activity of elicitor, which can trigger hypersensitive response and reactive oxygen species burst in leaves as well as enhanced rice plant growth. The effects of EsxA on seedling blight (Fusarium oxysporum) resistance and gene transcription, including pathogenesis-related (PR) genes in rice were evaluated. The germination rate was 95.0% for seeds treated with EsxA and then inoculated with F. oxysporum, which was 2.8-times higher than that of F. oxysporum-infected control seeds that were not treated with EsxA (Con). The buds and roots of EsxA-treated seedlings were 2.4- and 15.9-times longer than those of Con seedlings. The plants and roots of seedlings dipped in an EsxA solution and then inoculated with F. oxysporum were longer than those of the Con seedlings. Theplant length, number of total roots, and number of white roots were respectively 23.2%, 1.74-times, and 7.42-times greater for the seedlings sprayed with EsxA and then inoculated with F. oxysporum than for the Con seedlings. The EsxA induction efficiency (spray treatment) on seedling blight resistance was 60.9%. The transcriptome analysis revealed 1137 and 239 rice genes with EsxA-induced up-regulated and down-regulated transcription levels, respectively. At 48 h after the EsxA treatment, the transcription of 611 and 160 genes was up-regulated and down-regulated, respectively, compared with the transcription levels for the untreated control at the same time-point. Many disease resistance-related PR genes had up-regulated transcription levels. The qPCR data were consistent with the transcriptome sequencing results. EsxA triggered rice ISR to seedling blight and gene differential transcription, including the up-regulated transcription of rice PR genes. These findings may be relevant for the use of EsxA as a protein elicitor to control plant diseases.

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