Soil-borne Fungal Pathogens Research Articles

Evaluation of F2:3 rice population resistant to Rhizoctonia solani Kuhn inciting sheath blight disease

Rice sheath blight caused by the soil-borne fungal pathogen Rhizoctonia solani Kuhn is an economically important disease in rice resulting in enormous yield losses worldwide. In the present investigation, a population constituting F3 lines resulted from the cross made between IC277332 (susceptible parent) and Tetep (resistant parent) were evaluated for sheath blight resistance and other agronomic traits over a season. The rice population lines were categorized into four groups viz., moderately resistant (11), moderately susceptible (63), susceptible (24), and highly susceptible (8), based on area under disease progress curve (AUDPC) values. During the study, nine moderate resistant lines showed, less AUDPC values in comparison to Tetep. Furthermore, 63 individuals (60%) exhibited moderate susceptibility with AUDPC values (677-987 per day). The principal component biplot analysis PC1 and PC2 showed 47.08% and 13.19% variation, respectively. The employment of Unweighted Pair Group Method of Arithmetic Means (UPGMA) cluster analysis led to the grouping of the 106 individuals into 2 major clusters A and B. The results suggested that none of the rice lines was resistant to sheath blight disease. However, few lines showed moderate resistance to the disease which can be exploited for the development of sheath blight-resistant cultivars.

Effects of Solubilised Orange Peels on the Occurrence of some Fungal Soil-borne Pathogens of Zea mays (L.)

Effects of Solubilised Orange Peels on the Occurrence of some Fungal Soil-borne Pathogens of Zea mays (L.)

Detection and Molecular Phylogenetic-Morphometric Characterization of Rhizoctonia tuliparum, Causal Agent of Gray Bulb Rot of Tulips and Bulbous Iris.

Gray bulb rot of tulips and bulbous iris is caused by the soil-borne fungal pathogen, Rhizoctonia tuliparum (Rtul). Sclerotia present in infected bulbs, as well as overwintering sclerotia in soil and field debris, are the primary sources of infection. A method for accurate and sensitive detection of Rtul from soil and infected bulbs, and estimation of inoculum threshold levels, is needed for the management of disease caused by this pathogen. We designed a unique set of primers targeting the ITS2 region of the Rtul genome and developed a highly sensitive quantitative PCR (qPCR)-based method for Rtul identification using these primers, where the threshold of detection was approximately 1 fg Rtul DNA. The assay was more sensitive with sclerotia collected from the field (natural) than with those grown in the lab, and more sensitive with natural-light than natural-dark sclerotia. Also, the detection method was more sensitive when sclerotia were extracted from soil than from bulb tissue. The qPCR method was highly specific, as no PCR amplification was detected when genomic DNA from 62 non-Rtul Rhizoctonia isolates from a wide range of anastomosis groups were tested. To understand the evolutionary relationships and genomic diversity of Rtul, we performed phylogenetics of the ITS1-5.8S-ITS2 region and ITS2-molecular morphometric characterization (MMC) of Rtul isolates. The three Rtul isolates whose ITS sequences were available in GenBank formed a distinct phylogenetic clade with Ceratobasidium anceps as the nearest relative. Furthermore, MMC analysis revealed genetic divergence among these three Rtul isolates.

In-silico analysis of the regulatory region of effector protein genes in Verticillium dahliae

Verticillium dahliae is a soil-borne fungal plant pathogen that infects more than 400 plant species throughout the world, causing huge economic losses annually. Due to its wide host range and adaptation strategy of producing resting structures, Verticillium infection and spread are difficult to control. The resting dormant melanized structures called microsclerotia, produced during the dormant stage of the pathogen can persist in soil for years and are the primary source of infection as they germinate after being stimulated by root exudates. The fungus secrets effector proteins that facilitate the primary infection and subsequent spread. In the current study, we used in silico tools to analyze effector proteins belonging to hydrophobin, necrosis, and ethylene inducing like-protein and polysaccharide lyase 3 protein family which are required for virulence and pathogenicity of the pathogen. Our study showed that the genes for these protein families consist of many paralogs. Some of these paralogous proteins display similar functions but differential expression during pathogenicity establishment. This study will provide information about cis-acting factors regulating differential regulation of paralogs during infection.

Biocontrol Activity of Nonpathogenic Strains of Fusarium oxysporum: Colonization on the Root Surface to Overcome Nutritional Competition.

Fusarium oxysporum is a soil-borne fungal pathogen that causes vascular wilts in a wide variety of crops. Certain nonpathogenic strains of F. oxysporum are known to protect crops against F. oxysporum pathogens. We assessed the biocontrol activities of nonpathogenic mutants of F. oxysporum ff. spp. melonis and lycopersici generated by disruption of the FOW2 gene, which encodes a Zn(II)2Cys6-type transcriptional regulator essential for their pathogenicity. Pre-inoculation of melon or tomato roots with strain ΔFOW2 conidia markedly reduced disease incidence caused by the parental wild-type strain in a concentration-dependent manner of conidial suspensions of ΔFOW2 strains. The biocontrol effect caused by the ΔFOW2 pre-inoculation lasted for at least 7 days. Pre-inoculation of melon roots with the wild-type or ΔFOW2 strain of F. oxysporum f. sp. lycopersici and nonpathogenic F. oxysporum strain also led to biocontrol activity against F. oxysporum f. sp. melonis, indicating that the biocontrol activity of ΔFOW2 strains is due to its nonpathogenic nature, not to the FOW2 disfunction. Conidial germination and hyphal elongation of only the wild-type strain were inhibited on melon root surface pre-inoculated with conidia of strains nonpathogenic to melon plants. Expression of defense-related genes was not significantly induced in roots and aboveground parts of melon seedlings preinoculated with ΔFOW2 conidia. Carbon source competition assay showed that nonpathogenic strains competed with the wild-type strain for a carbon source in soil. Strain ΔFOW2 also competed with the oomycete pathogen Pythium aphanidermatum for carbon source and protected melon plants from P. aphanidermatum. Our results suggest that the biocontrol activity of the nonpathogenic F. oxysporum strains used in this study mainly depends on their extensive colonization of the root surface and outcompeting pathogens for nutrients.

Effects of Bacillus amyloliquefaciens QSB-6 on the Growth of Replanted Apple Trees and the Soil Microbial Environment

Apple replant disease (ARD), caused largely by soil-borne fungal pathogens, has seriously hindered the development of the apple industry. The use of antagonistic microorganisms has been confirmed as a low-cost and environmentally friendly means of controlling ARD. In the present study, we assessed the effects of Bacillus amyloliquefaciens QSB-6 on the growth of replanted apple saplings and the soil microbial environment under field conditions, thus providing a theoretical basis for the successful use of microbial biocontrol agents. Four treatments were implemented in three apple orchards: untreated replant soil (CK1), methyl bromide fumigation (CK2), blank carrier treatment (T1), and QSB-6 bacterial fertilizer treatment (T2). The plant height, ground diameter, and branch length of apple saplings treated with T2 in three replanted apple orchards were significantly higher than that of the CK1 treatment. Compared with the other treatments, T2 significantly increased the number of soil bacteria, the proportion of actinomycetes, and the activities of soil enzymes. By contrast, compared with the CK1 treatments, the phenolic acid content, the number of fungi, and the abundance of Fusarium oxysporum, Fusarium moniliforme, Fusarium proliferatum, and Fusarium solani in the soil were significantly reduced. PCoA and cluster analysis showed that soil inoculation with strain QSB-6 significantly decreased the Mcintosh and Brillouin index of soil fungi and increased the diversity of soil bacteria in T2 relative to CK1. The soil bacterial community structure in T2 was different from the other treatments, and the soil fungal communities of T2 and CK2 were similar. In summary, QSB-6 bacterial fertilizer shows promise as a potential bio-inoculum for the control of ARD.

Development of PCR-Based Race-Specific Markers for Differentiation of Indian Fusarium oxysporum f. sp. cubense, the Causal Agent of Fusarium Wilt in Banana.

Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc), is the most lethal soil-borne fungal pathogen infecting bananas. Foc race 1 (R1) and 4 (R4) are the two most predominant races affecting the economically important Cavendish group of bananas in India. A total of seven vegetative compatibility groups (VCGs) from three pathogenic races were isolated during our field survey and were found to be highly virulent towards cv. Grande Naine. According to comparative genome analyses, these Indian Foc VCGs were diverse in genomic organization and effector gene profiles. As a result, false-positive results were obtained with currently available molecular markers. In this context, the study has been initiated to develop PCR-based molecular markers for the unambiguous identification of Indian Foc R1 and R4 isolates. Whole-genome sequences of Foc R1 (GCA_011316005.3), Foc TR4 (GCA_014282265.3), and Foc STR4 (GCA_016802205.1), as well as the reference genomes of Foc (ASM799451v1) and F. oxysporum f. sp. lycopersici (Fol; ASM14995v2), were aligned to identify unique variable regions among the Foc races. Using putative chromosome and predicted gene comparison, race-specific unique Foc virulence genes were identified. The putative lineage-specific identified genes encoding products secreted in xylem (SIX) that may be necessary for disease development in the banana. An in silico analysis was performed and primers were designed from a region where sequences were dissimilar with other races to develop a specific marker for Foc R1, R4, TR4, and STR4. These race-specific markers allowed target amplification in the characterized highly virulent Foc isolates, and did not show any cross-amplification to any other Foc races, VCGs or banana pathogens, Fusarium species, and non-pathogenic Fusarium oxysporum isolates. The study demonstrated that the molecular markers developed for all the three Foc races of India could detect the pathogen in planta and up to 0.025 pg µL−1 DNA levels. Thus, the markers developed in this study are novel and could potentially be useful for the accurate diagnosis and detection of the Indian Foc races which are important for the effective management of the disease.

Differentiation of the Pea Wilt Pathogen Fusarium oxysporum f. sp. pisi from Other Isolates of Fusarium Species by PCR.

Pea wilt disease, caused by the soilborne and seedborne fungal pathogen Fusarium oxysporum f. sp. pisi (Fop), first appeared in Japan in 2002. We herein investigated the molecular characteristics of 16 Fop isolates sampled from multiple locations and at different times in Japan. The 16 isolates were divided into three clades in molecular phylogenic ana­lyses based on both the TEF1α gene and the rDNA-IGS region. All of the Fop isolates harbored a PDA1 gene, which encodes the cytochrome P450 pisatin demethylase (Pda1), and also carried one or both of the SIX6 and SIX13 genes, which encode secreted in xylem (Six) proteins. Other forms of F. oxysporum and other species of Fusarium did not carry these sets of genes. Based on these results, a PCR method was developed to identify Fop and differentiate it from other forms and non-pathogenic isolates of Fusarium spp. We also demonstrated that the PCR method effectively detected Fop in infected pea plants and infested soils.

Occurrence of Macrophomina phaseolina in Israel: Challenges for Disease Management and Crop Germplasm Enhancement.

Macrophomina phaseolina is a soil-borne fungal pathogen infecting many important crop plants. The fungus, which can survive on crop debris for a long period of time, causes charcoal rot disease by secreting a diverse array of cell-wall degrading enzymes and toxins. M. phaseolina thrives during periods of high temperatures and arid conditions, as typically occur in Israel and other countries with a Mediterranean climate. Crop losses due to charcoal rot can be expected to increase and spread to other countries in a warming global climate. Management of this pathogen is challenging, requiring an array of approaches for the various crop hosts. Approaches that have had some success in Israel include grafting of melons and watermelons on resistant squash rootstocks and soil application of fungicide to reduce disease incidence in melons, fumigation and alterations in planting date and mulching of strawberries, and alteration in irrigation regime of cotton. Elsewhere, these approaches, as well as soil amendments and addition of organisms that are antagonistic to M. phaseolina, have had success in some crop situations. Management through host resistance would be the most sustainable approach, but it requires identifying a resistant germplasm for each crop and introgressing the resistance into the leading cultivars. Resistance to charcoal rot is under complex genetic control in most crops, posing a great challenge for its introgression into elite germplasm. Moreover, fast, reliable methods of screening for resistance would have to be developed for each crop. The toothpick-inoculation method used by us holds great promise for selecting resistant germplasm for melons and possibly for sesame, but other methodologies have to be devised for each individual crop.

Nonphytotoxic copper oxide nanoparticles are powerful “nanoweapons” that trigger resistance in tobacco against the soil-borne fungal pathogen Phytophthora nicotianae

Investigations into the potential application of nanoparticles acting as nanofungicides in sustainable agriculture are rapidly expanding due to the high antimicrobial properties of these compounds, which do not risk inducing pathogen resistance to fungicides. A detailed understanding of the impact of copper oxide nanoparticles (CuO NPs) on soil-borne phytopathogenic fungi is yet to be obtained. This study aimed to explore the in vitro antifungal activity and control efficacy of CuO NPs applied via irrigation with respect to tobacco black shank (TBS) disease caused by Phytophthoranicotianae. The results revealed that CuO NPs greatly interfered with the reproductive growth process of this fungus, repressing hyphal growth, spore germination and sporangium production. Additionally, morphological damage, intracellular ROS accumulation and increased SOD enzyme activity in hyphae were the antifungicidal mechanisms of these NPs. In pot experiments, treatment with CuO NPs at 100 mg L−1 significantly suppressed TBS development, compared with the effect on control plants, and the control efficacy reached 33.69% without inducing phytotoxicity. Exposure to CuO NPs significantly activated a series of defense enzymes, and resistance genes in tobacco can further explain the mechanisms by which CuO NPs suppressed fungal infection. The Cu content in both the leaves and roots of P. nicotianae-infested plants increased by 50.03 and 27.25%, respectively, after treatment with 100 mg L−1 CuO NPs, compared with that of healthy plants. In particular, a higher Cu content was observed in infected roots than in leaves. Therefore, this study showed the potential of CuO NPs applied as nanofungicides and as nanoinducers of fungus resistance genes for the management of TBS through inhibition of pathogen infection and stimulation of plant defenses.

Evaluation of Some Biological and Chemical Elements in Controlling Some Soil-borne Fungi and Stimulating Plant Growth

This study was conducted to evaluate the efficacy of the biocontrol fungi Chaetomium cupreum, Trichoderma viride, and Saccharomyces cerevisiae and some chemical nutrients that stimulate plant growth, such as calcium nitrate, ammonium phosphate, aqueous magnesium sulfate, copper and boron in controlling some common soil-borne pathogenic fungi and evaluating their role in stimulating plant growth. All the bioagents showed significant antagonistic efficiency In vitro against the pathogenic fungi Drechslera Halodes, Fusarium oxysporum, Fusarium solani, Macrophomina phaseolina, Pythium aphanidermatum and Rhizoctonia solani. Under greenhouse conditions, BC treatment composed of biological and chemical elements, achieved the highest germination rate for tomato, cucumber and cowpea seeds inoculated with the pathogenic fungi, and reached 95.83-100.00% compared to 36.67- 47.50% for the control treatment. BC treatment also excelled in reducing disease incidence and severity, as the disease rate reached 0% compared to 95.83-99.17 % for the inoculated control treatment, and without significant difference with the non-inoculated (healthy) control. In addition, the BC treatment produced 0 % disease severity rate as compared to 82.58-85.83% for the inoculated control, and without significant difference with non-inoculated control. Furthermore, the BC treatment was superior to the rest of the treatments in increasing dry weight of all the plant species tested. Keywords: Chaetomium cupreum, Trichoderma viride, Saccharomyces cerevisia, Soil-borne fungi, biological control.

THE COMPOST, A SOURCE OF PLANT BENEFICIAL BACTERIA WITH BIOCONTROL POTENTIAL

Recycling the sewage sludge from treatment plants is a common activity. The resulting compost is usually rich in plant nutrients and beneficial microorganisms. However, compost properties greatly differ depending on the nature of the fermented biomass and fermentation processes. The aim of this study was to analyze the microbial load of three different composts, in order to detect new bacterial strains with plant protection properties. Isolated bacteria were microbiologically characterized and evaluated for their potential to reduce soil-borne phytopathogenic fungi. Results showed a microbial load of approximately 106 CFU/g of compost. In the analyzed samples it was revealed that as bacterial load increases, the fungal amount decreases. Analyzing some newly isolated bacteria obtained from these composts, a good biocontrol potential against soil-borne pathogenic fungi was revealed. Some of the isolated bacterial strains revealed antifungal activity against Rhizoctonia solani and Sclerotinia sclerotiorum. These bacteria showed good colonization capacity and lytic enzymes production, correlated to antimicrobial activity. These compost-originated bacteria reveal high potential in pathogens inhibition. Therefore, the analyzed composts are recommended not only as soil fertility improvers, but also as potential suppressors of soil-borne pathogens. Results revealed these composts as source of plant beneficial bacteria with biological control potential.

A COMPREHENSIVE NOTE ON TRICHODERMA AS A POTENTIAL BIOCONTROL AGENT AGAINST SOIL BORNE FUNGAL PATHOGENS: A REVIEW

The extensive use of synthetic pesticides has a harmful impact on the environment, plants and animal health. It is a big challenge for all farming systems to develop novel approaches, which are eco-friendly and improve food quality. As compared to synthetic pesticides, the use of beneficial microbes is the best option to maintain the environmental condition because they are cost-effective and ecofriendly. In the recent era, biological antagonistic microorganisms (Trichoderma spp.) are the best approach to control the soil-borne fungal pathogens associated with plant roots of agriculturally important crops. Due to fast growth and rhizospheric colonization ability, this fungus competes with other pathogenic soil-borne fungi by producing different metabolites (volatile and non-volatile). Trichoderma protected the plants from pathogenic fungi through mycoparasitic and antibiosis capability. Furthermore, it has the ability to improve plant health by inducing SAR (Systemic acquired resistance), ISR (Induce systemic resistance), producing antifungal enzymes (α-1, 3-glucanases, Trichodermaketone, and trichodermin) and antioxidant enzymes that strengthen the immune system by increasing activities of guaiacol peroxidase (GPX), ascorbate peroxidase (APX), catalase (CAT) and superoxide dismutase (SOD) after pathogen attack. Development of bio-fungicide formulation by using the spore of Trichoderma species (T. harzianum, T. viride, and T. virens) are most effective against soil-borne pathogenic fungi at different concentrations and temperatures. This review article has significantly focused on gathering and summarizing the most recent literature to highlight the visible production and application of Trichoderma as a biomonitoring and biocontrol agent in plant diseases management program.

EVALUATION OF FUNGICIDES AGAINST PHYTOPHTHORA AND FUSARIUM (root rot spp.) OF CITRUS ROOTSTOCKS SEEDLINGS

Citrus is one of the most important fruit crop in the world and is usually grown through grafting technique. Rootstock is one of the significant part in grafted plants and has crutial effect on production, including yield, fruit quality, tree size, tolerance to salts and diseases, and scion compatibility. Citrus is susceptible to several fungal pathogens causing incalculable losses to the crop. Among all soil-borne fungal pathogens, Phytophthora and Fusarium cause the most severe damage to the nursery or orchards plants. This research was planned to evaluate the effectiveness of fungicides as soil drenching and root dipping to control Phytophthora and Fusarium attacking citrus rootstock seedlings at the nursery stage. Different physiological and morphological parameters were studied in the infected plants and data were compared with that of control. The data were recorded and compared concerning rootstock seed and seeding response using standard measures and statistical analysis. The results showed that plants inoculated with Phytophthora and Fusarium root rot spp.when treated with Aliette and Ridomil Gold showed maximum root shoot ratio, fresh dry weight ratio, photosynthetic rate, stomatal conductance, water potential and transpiration rate as compared to untreated plants. The results also depicted that plants treated with Aliette and Ridomil Gold through soil drenching have maximum root shoot ratio, fresh dry weight ratio, photosynthetic rate, stomatal conductance and transpiration rate as compared to root dipped plants. Keywords: Fungal diseases, pathogens, root rot, nursery plants.

DNA cleavage of the fungal pathogen and production of antifungal compounds are the possible mechanisms of action of biocontrol agent Penicillium italicum against Macrophomina phaseolina

ABSTRACT In the present study, five Penicillium species, namely, P. italicum, P. expansum, P. simplicissimum, P. oxalicum, and P. citrinum, were identified using ITS (internal transcribed spacer) and β-tubulin markers and screened for their in vitro antagonistic potential against a soil-borne fungal pathogen, Macrophomina phaseolina, in a dual-culture plate assay. Among all the tested strains, P. italicum showed the highest antagonistic potential against M. phaseolina by reducing its growth up to 57% over control, followed by P. citrinum (42%), P. simplicissimum (21%), P. expansum (11%), and P. oxalicum (9%). In order to find out the mechanism of action of P. italicum, genomic DNA of M. phaseolina was exposed to P. italicum secondary metabolites. The findings showed that these metabolites completely degraded the fungal DNA after the 48-h incubation period. To further explore the antifungal mechanism of action of P. italicum, chloroform and ethyl acetate fractions of its metabolites were subjected to gas chromatography–mass spectrometry (GC-MS) analysis. The major compounds identified in these fractions were 9,12-octadecadienoic acid (Z,Z)- (25.19%), decane (19.72%), dodecane (18.05%), benzene, nitro- (14.62%), benzene, 1,3,5-trimethyl (14.37%), benzene, 1,4-diethyl (11.62%), 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester (9.02%), and 1-nonadecene (8.99%), which could be responsible for control of M. phaseolina growth.

RETRACTED: Montiel-Rozas et al. Effect of Plant Extracts and Metam Sodium on the Soilborne Fungal Pathogens, Meloidogyne spp., and Soil Microbial Community. Agronomy 2020, 10, 513

Following publication [...]

The influence of rhizosphere soil fungal diversity and complex community structure on wheat root rot disease.

Wheat root rot disease due to soil-borne fungal pathogens leads to tremendous yield losses worth billions of dollars worldwide every year. It is very important to study the relationship between rhizosphere soil fungal diversity and wheat roots to understand the occurrence and development of wheat root rot disease. A significant difference in fungal diversity was observed in the rhizosphere soil of healthy and diseased wheat roots in the heading stage, but the trend was the opposite in the filling stage. The abundance of most genera with high richness decreased significantly from the heading to the filling stage in the diseased groups; the richness of approximately one-third of all genera remained unchanged, and only a few low-richness genera, such as Fusarium and Ceratobasidium, had a very significant increase from the heading to the filling stage. In the healthy groups, the abundance of most genera increased significantly from the heading to filling stage; the abundance of some genera did not change markedly, or the abundance of very few genera increased significantly. Physical and chemical soil indicators showed that low soil pH and density, increases in ammonium nitrogen, nitrate nitrogen and total nitrogen contributed to the occurrence of wheat root rot disease. Our results revealed that in the early stages of disease, highly diverse rhizosphere soil fungi and a complex community structure can easily cause wheat root rot disease. The existence of pathogenic fungi is a necessary condition for wheat root rot disease, but the richness of pathogenic fungi is not necessarily important. The increases in ammonium nitrogen, nitrate nitrogen and total nitrogen contributed to the occurrence of wheat root rot disease. Low soil pH and soil density are beneficial to the occurrence of wheat root rot disease.

Phenolics mediate suppression of Fusarium oxysporum f. sp. cubense TR4 by legume root exudates

Fusarium oxysporum Schlecht f. sp. cubense (E.F. Smith) Snyder & H.N. Hansen (Foc) is a notorious soil-borne fungal pathogen that causes Fusarium wilt disease of bananas (Musa spp. L.). Foc, especially Tropical Race 4 (TR4), is particularly devastating due its ability to infect diverse banana cultivars including Cavendish bananas. Fusarium wilt is difficult to manage, but intercropping has been reported to efficiently suppress Fusarium wilt through exudation of root metabolites with antagonistic effects on Foc. Yet, the metabolites that inhibit Foc and the underlying mode of action remain unclear. Hydroponic culture and targeted metabolite profiling were used to investigate the potential of root-exuded phenolic acids and flavonoids of two legume species, Desmodium uncinatum (Jacq.) DC. and Mucuna pruriens (L.) DC., to inhibit growth and the biosynthesis of the phytotoxins beauvericin and fusaric acid (FA) in Foc TR4. Of the twelve metabolites targeted, four phenolic acids (benzoic, t-cinnamic, p-coumaric, p-hydroxybenzoic) were common in root exudates of both legumes, whereas vanillin and the flavonoid quercetin were only detected in root exudates of M. pruriens. Bioassays using synthetic benzoic-, t-cinnamic-, or p-hydroxybenzoic acid, or a mixture thereof, showed a concentration-dependent suppressive effect on Foc TR4. Low concentrations of phenolic acids (0.01 and 0.1 mM) inhibited chlamydospore germination and the production of macro- and micro-conidia, as well as the biosynthesis of FA. Mycelial growth of Foc TR4 was only inhibited at high concentrations (1 mM) of benzoic acid, t-cinnamic acid, and a mixture of the three phenolics. This study demonstrates that phenolics in root exudates of D. uncinatum and M. pruriens suppress Foc TR4 by directly inhibiting the early stages of pathogen development. Intercropping banana with D. uncinatum and M. pruriens may thus be considered as a valuable option for suppression of Foc TR4.

Biocontrol prospective of Bacillus siamensis-AMU03 against Soil-borne fungal pathogens of potato tubers

Biocontrol prospective of Bacillus siamensis-AMU03 against Soil-borne fungal pathogens of potato tubers

Biochar and Trichoderma spp. in management of plant diseases caused by soilborne fungal pathogens: a review and perspective

A better understanding of the use of biochar with Trichoderma spp. (TRI), considered the most studied tool for biological control, would increase our ability to set priorities. However, no studies exist using the two inputs on plant disease management. Here, we hypothesized that biochar and TRI would be used for the management of soilborne plant pathogens, mainly due to changes in soil properties and its interactions. To test this hypothesis, this review assesses papers that used biochar and TRI against plant diseases and we summarize the handling mechanisms for each input. Biochar acts by mechanisms: induction to plant resistance, sorption of allelopathic and fungitoxic compounds, increase of beneficial microorganisms, changes the soil properties that promote health and nutrient availability. Trichoderma as biocontrol agents by different mechanisms: mycoparasitism, enzyme and secondary metabolic production, plant promoter agent, natural decomposition agent, and biological agent of bioremediation. Overall, our findings expand our knowledge about the reuse of wastes transformed in biochar combined with Trichoderma has potential perspective to formulate products as alternative management tool of plant disease caused by soilborne fungal pathogen and add important information that can be suitable for development of strategy for use in the global health concept.