Mechanisms of action and biocontrol potential of Trichoderma against fungal plant diseases - A review

Pesticides are chemicals used to control pests, such as aquatic weeds, insects, aquatic snails, and plant diseases. They are extensively used in forestry, agriculture, veterinary practices, and of great public health importance. Pesticides can be categorized according to their use into three major types (namely insecticides, herbicides, and fungicides). Water contamination by pesticides is known to induce harmful impacts on the production, reproduction, and survivability of living aquatic organisms, such as algae, aquatic plants, and fish (shellfish and finfish species). The literature and information present in this review article facilitate evaluating the toxic effects from exposure to various fish species to different concentrations of pesticides. Moreover, a brief overview of sources, classification, mechanisms of action, and toxicity signs of pyrethroid insecticides in several fish species will be illustrated with special emphasis on Cypermethrin toxicity.

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Biocontrol Potential of Essential Oils in Organic Horticulture Systems: From Farm to Fork

Frontiers in Nutrition ◽

10.3389/fnut.2021.805138 ◽

2022 ◽

Vol 8 ◽

Author(s):

Yuru Chang ◽

Philip F. Harmon ◽

Danielle D. Treadwell ◽

Daniel Carrillo ◽

Ali Sarkhosh ◽

...

Keyword(s):

Natural Products ◽

Essential Oils ◽

Water Solubility ◽

Scientific Evidence ◽

Plant Diseases ◽

Biocontrol Agents ◽

Market Demand ◽

High Volatility ◽

Biocontrol Potential ◽

Organic Horticulture

In recent decades, increasing attention has been paid to food safety and organic horticulture. Thus, people are looking for natural products to manage plant diseases, pests, and weeds. Essential oils (EOs) or EO-based products are potentially promising candidates for biocontrol agents due to their safe, bioactive, biodegradable, ecologically, and economically viable properties. Born of necessity or commercial interest to satisfy market demand for natural products, this emerging technology is highly anticipated, but its application has been limited without the benefit of a thorough analysis of the scientific evidence on efficacy, scope, and mechanism of action. This review covers the uses of EOs as broad-spectrum biocontrol agents in both preharvest and postharvest systems. The known functions of EOs in suppressing fungi, bacteria, viruses, pests, and weeds are briefly summarized. Related results and possible modes of action from recent research are listed. The weaknesses of applying EOs are also discussed, such as high volatility and low stability, low water solubility, strong influence on organoleptic properties, and phytotoxic effects. Therefore, EO formulations and methods of incorporation to enhance the strengths and compensate for the shortages are outlined. This review also concludes with research directions needed to better understand and fully evaluate EOs and provides an outlook on the prospects for future applications of EOs in organic horticulture production.

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Nanoparticles as Potential Antivirals in Agriculture

Agriculture ◽

10.3390/agriculture10100444 ◽

2020 ◽

Vol 10 (10) ◽

pp. 444

Author(s):

Marcela Vargas-Hernandez ◽

Israel Macias-Bobadilla ◽

Ramon Gerardo Guevara-Gonzalez ◽

Enrique Rico-Garcia ◽

Rosalia Virginia Ocampo-Velazquez ◽

...

Keyword(s):

Beneficial Effect ◽

Physicochemical Properties ◽

Metal Oxides ◽

Metal Nanoparticles ◽

Mechanisms Of Action ◽

Plant Diseases ◽

Antiviral Property ◽

Interaction Processes ◽

Antiviral Effects ◽

Wide Range

Viruses are estimated to be responsible for approximately 50% of the emerging plant diseases, which are difficult to control, and in some cases, there is no cure. It is essential to develop therapy practices to strengthen the management of these diseases caused by viruses in economically important crops. Metal nanoparticles (MeNPs) possess diverse physicochemical properties that allow for them to have a wide range of applications in industry, including nanomedicine and nano-agriculture. Currently, there are reports of favorable effects of the use of nanoparticles, such as antibacterial, antifungal, and antiviral effects, in animals and plants. The potential antiviral property of MeNPs makes them a powerful option for controlling these histological agents. It is crucial to determine the dosage of NPs, the application intervals, their effect as a biostimulant, and the clarification of the mechanisms of action, which are not fully understood. Therefore, this review focuses on discussing the ability of metal nanoparticles and metal oxides to control viruses that affect agriculture through an exhaustive analysis of the characteristics of the particles and their interaction processes for a possibly beneficial effect on plants.

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Genome Characteristics Reveal the Biocontrol Potential of Actinobacteria Isolated From Sugarcane Rhizosphere

Frontiers in Microbiology ◽

10.3389/fmicb.2021.797889 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zhen Wang ◽

Manoj Kumar Solanki ◽

Zhuo-Xin Yu ◽

Muhammad Anas ◽

Deng-Feng Dong ◽

...

Keyword(s):

Plant Growth ◽

Plant Pathogens ◽

Growth Promotion ◽

Pathogenic Fungi ◽

Plant Diseases ◽

Defense Enzyme ◽

Plant Growth Promoting ◽

Related Enzyme ◽

Biocontrol Potential

To understand the beneficial interaction of sugarcane rhizosphere actinobacteria in promoting plant growth and managing plant diseases, this study investigated the potential role of sugarcane rhizospheric actinobacteria in promoting plant growth and antagonizing plant pathogens. We isolated 58 actinobacteria from the sugarcane rhizosphere, conducted plant growth-promoting (PGP) characteristics research, and tested the pathogenic fungi in vitro. Results showed that BTU6 (Streptomyces griseorubiginosus), the most representative strain, regulates plant defense enzyme activity and significantly enhances sugarcane smut resistance by regulating stress resistance-related enzyme (substances (POD, PAL, PPO, TP) in sugarcane) activity in sugarcane. The genomic evaluation indicated that BTU6 has the ability to biosynthesize chitinase, β-1,3-glucanase, and various secondary metabolites and plays an essential role in the growth of sugarcane plants under biotic stress. Potential mechanisms of the strain in improving the disease resistance of sugarcane plants and its potential in biodegrading exogenous chemicals were also revealed. This study showed the importance of sugarcane rhizosphere actinobacteria in microbial ecology and plant growth promotion.

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Trichoderma viride Controls Macrophomina phaseolina through its DNA disintegration and Production of Antifungal Compounds

International Journal of Agriculture and Biology ◽

10.17957/ijab/15.1743 ◽

2021 ◽

Vol 25 (04) ◽

pp. 888-894

Author(s):

Iqra Haider Khan

Keyword(s):

Octanoic Acid ◽

Trichoderma Viride ◽

Macrophomina Phaseolina ◽

Mechanisms Of Action ◽

Degraded Dna ◽

Dual Culture ◽

Hexadecanoic Acid ◽

Universal Primer ◽

Trichoderma Spp ◽

Biocontrol Potential

Macrophomina phaseolina is a highly destructive pathogen of more than 500 plant species. It is difficult to eradicate it through chemical means as no patented fungicide is available against this pathogen. Biological control is the possible alternative method for its suitable management. The present study was carried out to evaluate the biocontrol potential of five Trichoderma spp. against M. phaseolina and the possible mechanisms of action. Identifications of all the Trichoderma spp. viz. T. hamatum, T. harzianum, T. koningii, T. longipile and T. viride were confirmed on molecular basis by using two universal primer pairs namely ITS and EF1. Their biocontrol potential was evaluated in dual culture plate method where T. viride showed the highest inhibitory efficacy (63%) against M. phaseolina. T. koningii, T. hamatum and T. longipile showed akin effects by arresting growth of the pathogen by 46–47% followed by T. harzianum (28%). To find out the mechanisms of action, secondary extrolites of the best biocontrol fungus T. viride were tested against the pathogenic genomic DNA where all the concentrations partially degraded DNA bands after 24 h of incubation and a complete DNA band disappearance was noted after 48 h incubation. In addition, T. viride culture filtrates were partitioned with chloroform and ethyl acetate and subjected to GC-MS analysis for identification of potential antifungal constituents. The most abundant identified volatile compounds in the two organic solvent fractions were 9,12-octadecadienoic acid (Z,Z)- (44.54%), n-hexadecanoic acid (24.02%), hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester (14.25%), 9-tricosene, (Z)- (10.43%) and [1,1'-bicyclopropyl]-2-octanoic acid, 2'-hexyl-, methyl ester (10.43%). To conclude, T. viride was the best biocontrol agent against M. phaseolina and acts against the pathogen by DNA disintegration and production of antifungal secondary metabolites. © 2021 Friends Science Publishers

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Use of Plant Growth-Promoting Bacteria for Biocontrol of Plant Diseases: Principles, Mechanisms of Action, and Future Prospects

Applied and Environmental Microbiology ◽

10.1128/aem.71.9.4951-4959.2005 ◽

2005 ◽

Vol 71 (9) ◽

pp. 4951-4959 ◽

Cited By ~ 1225

Author(s):

Stéphane Compant ◽

Brion Duffy ◽

Jerzy Nowak ◽

Christophe Clément ◽

Essaïd Ait Barka

Keyword(s):

Plant Growth ◽

Mechanisms Of Action ◽

Plant Diseases ◽

Plant Growth Promoting Bacteria ◽

Future Prospects ◽

Plant Growth Promoting ◽

Growth Promoting

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Effectiveness of the chemical stabilizers of Talaromyces flavus in biological control of tomato and greenhouse cucumber vascular wilt disease

Journal of Plant Protection Research ◽

10.1515/jppr-2016-0045 ◽

2016 ◽

Vol 56 (3) ◽

pp. 291-297 ◽

Cited By ~ 4

Author(s):

Donya Bahramian ◽

Laleh Naraghi ◽

Asghar Heydari

Keyword(s):

Fusarium Wilt ◽

Wilt Disease ◽

Plant Diseases ◽

Randomized Experiment ◽

Vascular Wilt ◽

Talaromyces Flavus ◽

Greenhouse Cucumber ◽

Fungal Antagonist ◽

Biocontrol Potential ◽

Vascular Wilt Disease

AbstractFungal antagonist,Talaromyces flavus, is one of the most important biological agents of soil-borne fungal diseases including Verticillium and Fusarium wilt. In this study, to increase the effectiveness ofT. flavusisolates obtained from greenhouse cucumbers and field grown tomatoes five chemical stabilizers were evaluated. Based on the results of previous studies, the most effective substrate for the growth, sporulation and stability ofT. flavusisolates related to the above-mentioned plants was a mix of rice bran and peatmoss. Different chemical stabilizers were mixed with the above-mentioned substrate containing spore suspensions of variousT. flavusisolates. For each plant, a completely randomized experiment was conducted under greenhouse conditions with seven treatments and three replications. The results of this study indicated that treatments containing sodium nitrate and D-cycloserine were more effective than those containing other stabilizers. The overall results of this study suggest that the use of some chemical stabilizers may enhance the biocontrol potential of fungal antagonists in controlling different plant diseases including Verticillium and Fusarium wilt.

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Case Formulation and Design of Behavioral Treatment Programs

European Journal of Psychological Assessment ◽

10.1027//1015-5759.19.3.164 ◽

2003 ◽

Vol 19 (3) ◽

pp. 164-174 ◽

Cited By ~ 27

Author(s):

Stephen N. Haynes ◽

Andrew E. Williams

Keyword(s):

Functional Analysis ◽

Behavior Problems ◽

Behavioral Treatment ◽

Clinical Case ◽

Relative Magnitude ◽

Mechanisms Of Action ◽

Treatment Programs ◽

Case Formulation ◽

Functional Relations ◽

Causal Variables

Summary: We review the rationale for behavioral clinical case formulations and emphasize the role of the functional analysis in the design of individualized treatments. Standardized treatments may not be optimally effective for clients who have multiple behavior problems. These problems can affect each other in complex ways and each behavior problem can be influenced by multiple, interacting causal variables. The mechanisms of action of standardized treatments may not always address the most important causal variables for a client's behavior problems. The functional analysis integrates judgments about the client's behavior problems, important causal variables, and functional relations among variables. The functional analysis aids treatment decisions by helping the clinician estimate the relative magnitude of effect of each causal variable on the client's behavior problems, so that the most effective treatments can be selected. The parameters of, and issues associated with, a functional analysis and Functional Analytic Clinical Case Models (FACCM) are illustrated with a clinical case. The task of selecting the best treatment for a client is complicated because treatments differ in their level of specificity and have unequally weighted mechanisms of action. Further, a treatment's mechanism of action is often unknown.

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