Growth Of Phytopathogenic Fungi Research Articles

Rhizobacteria Isolated from Amazonian Soils Reduce the Effects of Water Stress on the Growth of Açaí (Euterpe oleracea Mart.) Palm Seedlings.

Euterpe oleracea Mart., also known for its fruit açaí, is a palm native to the Amazon region. The state of Pará, Brazil, accounts for over 90% of açaí production. Demand for the fruit in national and international markets is increasing; however, climate change and diseases such as anthracnose, caused by the fungus Colletotrichum sp., lead to decreased production. To meet demand, measures such as expanding cultivation in upland areas are often adopted, requiring substantial economic investments, particularly in irrigation. Therefore, the aim of this study was to evaluate the potential of açaí rhizobacteria in promoting plant growth (PGPR). Rhizospheric soil samples from floodplain and upland açaí plantations were collected during rainy and dry seasons. Bacterial strains were isolated using the serial dilution method, and subsequent assays evaluated their ability to promote plant growth. Soil analyses indicated that the sampling period influenced the physicochemical properties of both areas, with increases observed during winter for most soil components like organic matter and C/N ratio. A total of 177 bacterial strains were isolated from rhizospheres of açaí trees cultivated in floodplain and upland areas across dry and rainy seasons. Among these strains, 24% produced IAA, 18% synthesized ACC deaminase, 11% mineralized organic phosphate, and 9% solubilized inorganic phosphate, among other characteristics. Interestingly, 88% inhibited the growth of phytopathogenic fungi of the genera Curvularia and Colletotrichum. Analysis under simulated water stress using Polyethylene Glycol 6000 revealed that 23% of the strains exhibited tolerance. Two strains were identified as Bacillus proteolyticus (PP218346) and Priestia aryabhattai (PP218347). Inoculation with these strains increased the speed and percentage of açaí seed germination. When inoculated in consortium, 85% of seeds germinated under severe stress, compared to only 10% in the control treatment. Therefore, these bacteria show potential for use as biofertilizers, enhancing the initial development of açaí plants and contributing to sustainable agricultural practices.

Phoma herbarum: A Potential Biocontrol Agent Against Weeds, that Promotes Wheat Growth

The usage of chemical weedicide adversely affects the soil fertility and environment. Hence, in order to reduce the use of chemical weedicide, current study was aimed to isolate plant pathogenic microorganisms from diseased weeds and evaluate their potential as a bioherbicide in wheat field. Twelve bacterial and thirty-one fungal isolates were screened to determine their bioherbicidal activity against prevalent weeds (Avena fatua, Phalaris minor, and Chenopodium album) by using detached leaf assay and in-vitro seed testing methods. Among the forty-three isolates, two potential isolates were selected for further studies. Potential fungal isolates DGL 8C and DGL 7A with significant bioherbicidal activity were molecularly (ITS sequencing) identified as Phoma herbarum R21 (GenBank ID- ON705696) and K_NESO2 (GenBank ID- ON705704). Phoma herbarum R21 was chosen for further research due to its superior herbicidal effect and positive influence on wheat growth. Effective herbicidal activity (up to 90%) of potential isolate was obtained in pre-germination testing, compared to control. Cell free culture filtrate (CFCF) treatment showed nonspecific inhibition in the germination of weeds and wheat. While, CFCF selectively deteriorated the target weeds in post-germination treatment. Phoma herbarum R21 enhanced the growth of Durum wheat varieties Poshan and Tejas, as it promoted the growth of shoot, root, and fresh weight up to 88% compared to control. Phoma herbarum R21 significantly inhibited the growth of phytopathogenic fungi up to 57%. In this study, Phoma herbarum R21 was identified as a potential bioherbicide against the weeds of wheat along with its growth promoting and antifungal activities.

Molecular Basis of Yeasts Antimicrobial Activity-Developing Innovative Strategies for Biomedicine and Biocontrol.

In the context of the growing concern regarding the appearance and spread of emerging pathogens with high resistance to chemically synthetized biocides, the development of new agents for crops and human protection has become an emergency. In this context, the yeasts present a huge potential as eco-friendly agents due to their widespread nature in various habitats and to their wide range of antagonistic mechanisms. The present review focuses on some of the major yeast antimicrobial mechanisms, their molecular basis and practical applications in biocontrol and biomedicine. The synthesis of killer toxins, encoded by dsRNA virus-like particles, dsDNA plasmids or chromosomal genes, is encountered in a wide range of yeast species from nature and industry and can affect the development of phytopathogenic fungi and other yeast strains, as well as human pathogenic bacteria. The group of the "red yeasts" is gaining more interest over the last years, not only as natural producers of carotenoids and rhodotorulic acid with active role in cell protection against the oxidative stress, but also due to their ability to inhibit the growth of pathogenic yeasts, fungi and bacteria using these compounds and the mechanism of competition for nutritive substrate. Finally, the biosurfactants produced by yeasts characterized by high stability, specificity and biodegrability have proven abilities to inhibit phytopathogenic fungi growth and mycelia formation and to act as efficient antibacterial and antibiofilm formation agents for biomedicine. In conclusion, the antimicrobial activity of yeasts represents a direction of research with numerous possibilities of bioeconomic valorization as innovative strategies to combat pathogenic microorganisms.

Response of Bacillus velezensis 83 to interaction with Colletotrichum gloeosporioides resembles a Greek phalanx-style formation: a stress resistant phenotype with antibiosis capacity

Plant growth-promoting rhizobacteria, such as Bacillus spp., establish beneficial associations with plants and may inhibit the growth of phytopathogenic fungi. However, these bacteria are subject to multiple biotic stimuli from their competitors, causing stress and modifying their development. This work is a study of an in vitro interaction between two model microorganisms of socioeconomic relevance, using population dynamics and transcriptomic approaches. Co-cultures of Bacillus velezensis 83 with the phytopathogenic fungus Colletotrichum gloeosporioides 09 were performed to evaluate the metabolic response of the bacteria under conditions of non-nutritional limitation. The bacterial response was associated with the induction of a stress-resistant phenotype, characterized by a lower specific growth rate, but with antimicrobial production capacity. About 12% of co-cultured B. velezensis 83 coding sequences were differentially expressed, including the up-regulation of the general stress response (sigB regulon), and the down-regulation of alternative carbon sources catabolism (glucose preference). Defense strategies in B. velezensis are a determining factor in order to preserve the long-term viability of its population. Mostly, the presence of the fungus does not affect the expression of antibiosis genes, except for those corresponding to surfactin/bacillomycin D production. Indeed, the up-regulation of antibiosis genes expression is associated with bacterial growth, regardless of the presence of the fungus. This behavior in B. velezensis 83 resembles the strategy used by the classical Greek phalanx formation: by sacrificing growth rate and metabolic versatility, resources can be redistributed to defense (stress resistant phenotype) while maintaining the attack (antibiosis capacity). The presented results are the first characterization of the molecular phenotype at the transcriptome level of a biological control agent under biotic stress caused by a phytopathogen without nutrient limitation.

New insights on the application of half‐sandwich complexes with metal–iodide bonds for agricultural fungicides

Cyclopentadienyl half‐sandwich complexes of cobalt and iron with metal–iodide bonds were reported to efficiently inhibit the growth of phytopathogenic fungi. With the aim of investigating the structure/activity relationships, further in vitro experiments were carried out. Cyclic voltammetric characterization, chemical stability, and antiradical activity were performed in two solvents: dimethyl sulfoxide and acetone. The iodide ion removal from the complex appears to be the key point of antifungal activity. Moreover, a preliminary cell viability test on human keratinocytes was also assessed in order to verify the nontoxic effect of tested compounds. The cytotoxicity for all the complexes was comparable with that shown by povidone iodide, a common antifungal agent recognized as safe (IC50 > 300 mM). Furthermore, the work proposes an additional roadmap (sequence of experiments) at the initial antifungal activity tests, which improves insight into their mechanism of action.

Chemical Profiling and Antifungal Activity of Ziziphora clinopodioides Leaf Essential Oil against the Pathogen Verticillium dahliae.

Essential oils (EOs) are often used as natural antifungal agents to control the growth of phytopathogenic fungi. The aim of this study was to determine the effect of Ziziphora clinopodioides leaf EO against Verticillium dahliae, a pathogenic fungus of cotton. Gas chromatography-mass spectrometry (GC/MS) analysis revealed the presence of 15 compounds of the total of extracted oil, which was consisted of 98.79 % monoterpenes and 0.61 % sesquiterpenes. The major constituents were pulegone (62.17 %), isomenthone (18.42 %), l-menthone (5.55 %) and piperitenone (3.99 %). The mycelial growth of Verticillium dahliae was completely inhibited at 0.24 μL/mL air under vapor phase condition. Considerable morphological variations were also observed in the fungal sclerotia at the contact phase at 3 μL/mL. This study demonstrated for the first time that Z. clinopodioides EO can effectively inhibit the growth of V. dahliae, implying that it has the potential to be explored as an antifungal agent against Verticillium Wilt of cotton.

Trypsin/α-Amylase Inhibitors from Capsicum chinense Seeds: Characterization and Antifungal Activity against Fungi of Agronomic Importance.

Protease inhibitors (PIs) have attracted attention due to their important roles in plant defense. The objective of this work was to characterize and evaluate the antimicrobial activity of the peptides of a family of serine PIs from Capsicum chinense Jacq. seeds. Initially, PIs were extracted from the seeds and subjected to purification by chromatography, resulting in three different peptide enriched fractions (PEFs) termed PEF1, PEF2 and PEF3. Subsequently, the PEF3 was subjected to trypsin inhibition assays, α-amylase activity assays, antimicrobial activity assays on phytopathogenic fungi, and assays to determine the likely mechanisms of action. The PEF3 was composed of three protein bands with molecular masses ranging between 6 and 14 kDa. The amino acid residues of the ~6 kDa band showed high similarity with serine PIs. PEF3 inhibited the activity of the enzymes trypsin, human salivary α-amylase, and Tenebrio molitor larval α-amylase and inhibited the growth of phytopathogenic fungi, showing 83.7% loss of viability in Fusarium oxysporum. PEF3 induced reactive oxygen species in Colletotrichum lindemuthianum and F. oxysporum to dissipate their mitochondrial membrane potential and activated caspases in C. lindemuthianum. Our results reinforce the importance of PIs in plant defense mechanisms against phytopathogenic fungi as well as in their biotechnological applications for the control of plant pathogens.

Endophytic Penicillium species secretes mycophenolic acid that inhibits the growth of phytopathogenic fungi.

The worldwide demand for reduced and restricted use of pesticides in agriculture due to serious environmental effects, health risks and the development of pathogen resistance calls for the discovery of new bioactive compounds. In the medical field, antibiotic-resistant microorganisms have become a major threat to man, increasing mortality. Endophytes are endosymbiotic microorganisms that inhabit plant tissues without causing any visible damage to their host. Many endophytes secrete secondary metabolites with biological activity against a broad range of pathogens, making them potential candidates for novel drugs and alternative pesticides of natural origin. We isolated endophytes from wild plants in Israel, focusing on endophytes that secrete secondary metabolites with biological activity. We isolated 302 different endophytes from 30 different wild plants; 70 of them exhibited biological activity against phytopathogens. One biologically active fungal endophyte from the genus Penicillium, isolated from a squill (Urginea maritima) leaf, was further examined. Chloroform-based extraction of its growth medium was similarly active against phytopathogens. High-performance liquid chromatography separation followed by gas chromatography/mass spectrometry analysis revealed a single compound-mycophenolic acid-as the main contributor to the biological activity of the organic extract.

Characterization of Paenibacillus spp. CBRM17 as antagonist of phytopathogenic fungi and growth promoter of Capsicum chinense Jacq.

Studies of the plant-microorganism relationship have made it posible to explore the potential of rhizospheric bacteria to improve the health and quality of plants. In the present study, Paenibacillus sp. CBRM17 was characterized in vitro for its ability to inhibit the growth of phytopathogenic fungi that cause diseases in horticultural crops in the tropics, finding a reduction in the mycelial growth of Alternaria, Fusarium and Helmintosphorium strains in the range of 50 to 70 %, additionally its biochemical properties related to the promotion of plant growth were characterized, registering the production of 0.36 µg/mL of indole acetic acid (IAA), the solubilization of tricalcium phosphate with solubilization index (SI) of 2.41 mm and solubilization efficiency (SE) of 140.6 %, producing in the supernatant 63.5 mg/L of soluble phosphorus, in addition to being positive for ACC deaminase activity. Inoculations trials of habanero chili (Capsicum chinense Jacq.) seeds with Paenibacillus sp. CBRM17 showed its potential to be used as an inoculant in the growth promotion of this crop, since it increased all growth variables; increasing the total fresh and dry biomass by 93.3 and 96.4 %, respectively.

Symbiotic and Antagonistic Functions of the Bacterium Burkholderia cepacia BsNLG8, from the Nilaparvata lugens (Stal)

Bacterial symbionts are widespread in insects and other animals. These microbes play crucial roles in many aspects of insect physiology and biology, including immunity, nutrition and confronting plant defenses. In the present study, we isolated and identified the bacterium Burkholderia cepacia BsNLG8 from the brown planthopper (BPHs), Nilaparvata lugens, a devastating pest of rice crops worldwide. Plate confrontation assay indicated that BsNLG8 significantly inhibited the growth of phytopathogenic fungi. In addition, the BsNLG8 strain demonstrated the ability to produce siderophores, which explains its antagonistic mechanism. Lastly, we explored the nicotine degradation ability of BsNLG8 using in vitro and in vivo methods. In vitro, HPLC analysis results showed that BsNLG8 could significantly reduce the concentration of nicotine in the medium at 36 h. Moreover, microinjection of BsNLG8 in axenic BPHs increased the survival rate of the host on nicotine-containing rice seedlings. These findings could serve as the basis of future research in deciphering the interaction between host and symbionts.

Cysts and alkylresorcinols of Azotobacter vinelandii inhibit the growth of phytopathogenic fungi

Azotobacter vinelandii is a Gram negative that undergo a morphological and physiological differentiation process to form cysts resistant to desiccation. The main components of a cyst are alkylresorcinols (ARs), phenolic lipids of 21 to 23 C. These lipids are homologous to plant ARs, where they have been reported to have antifungal properties. The objective of this study was to evaluate the antifungal capacities of vegetative cells and cysts of A. vinelandii AEIV. The cysts were visualized by optical microscope and the detection of ARs was performed by thin layer chromatography. Antagonism bioassay were carried out between vegetative cells and cysts against Fusarium brachygibbosum, Aspergillus niger and Colletotrichum gloeosporioides. We confirmed the induction of cysts and the presence of ARs of A. vinelandii AEIV. We observed that using 1×103 cysts reduced up to 76.3% (p < 0.05) the growth of the three phytopathogenic fungi and this result was not observed when using vegetative cells or the strain blocked in the synthesis of ARs. This shows that the cysts exert an antagonistic effect on phytopathogenic fungi and do so through the ARs, considering the development of an effective strategy to control pests in fungi that affect postharvest fruits.

Antifungal Activity, Structural Stability, and Immunomodulatory Effects on Human Immune Cells of Defensin from the Lentil Lens culinaris.

An increase in the frequency of mycoses and spreading of multidrug-resistant fungal pathogens necessitates the search for new antifungal agents. Earlier, we isolated the novel defensin from lentil Lens culinaris seeds, designated as Lc-def, which inhibited the growth of phytopathogenic fungi. Here, we studied an antifungal activity of Lc-def against human pathogenic Candida species, structural stability of the defensin, and its immunomodulatory effects that may help to prevent fungal infection. We showed that Lc-def caused 50% growth inhibition of clinical isolates of Candida albicans, C. krusei, and C. glabrata at concentrations of 25–50 μM, but was not toxic to different human cells. The lentil defensin was resistant to proteolysis by C. albicans and was not cleaved during simulated gastroduodenal digestion. By using the multiplex xMAP assay, we showed for the first time for plant defensins that Lc-def increased the production of such essential for immunity to candidiasis pro-inflammatory cytokines as IL-12 and IL-17 at the concentration of 2 μM. Thus, we hypothesized that the lentil Lc-def and plant defensins in general may be effective in suppressing of mucocutaneous candidiasis due to their antifungal activity, high structural stability, and ability to activate a protective immune response.

Application of Novel Biogenic nanoparticles for antimicrobial traits

Nanotechnology is a better approach to dealing with the current challenges of phytopathogens in agriculture and the environment. Nanoparticles (NPs) are less time-consuming, non-toxic and environmentally friendly and provide a high yield compared to conventional synthesis of NPs. Using plant growth promoting (PGP) bacterial strain for the synthesis of nanoparticles can route out the challenges of using chemical-based fertilizers and pesticides for agriculture. In our study, silver nanoparticles (AgNPs) were synthesized by using Burkholderia sp. 15B, which were further characterized by various physical techniques. All the techniques suggested the formation of biogenic NPs. We found that the bacteria-based NPs were able to hamper the growth of phytopathogenic fungi by more than 80%, as examined by the inhibition of fungal growth in the presence of green NPs. In addition, the synthesized NPs efficiently rescued seedlings from phytopathogenic fungal invasion. The results implicate the use of microorganism-mediated AgNPs as pesticides over chemical-based pesticides.

A Mycorrhizal Bacteria Strain Isolated From Polyporus umbellatus Exhibits Broad-Spectrum Antifungal Activity.

The microbes in the rhizosphere (or mycorrhizosphere) could promote plant growth, however, it is unclear whether mycorrhizosphere microbes could fight multiple fungal pathogens. In this study, twenty-one bacterial strains distributed in 6 genera, including 5 Pseudomonas strains, were isolated from mycorrhizal samples of Polyporus umbellatus that rely on other fungi during their life cycles. Further screening and pot experiments showed that the Pseudomonas strain ZL8 not only inhibited the growth of phytopathogenic fungi, but also promoted the growth of Salvia miltiorrhiza through inhibiting its wilting. In addition, strain ZL8 was found to have the ability to dissolve phosphate, produce IAA and siderophore. Nineteen compounds were identified from the fermentation broth of strain ZL8, of which 2,4-diacetylphloroglucinol (DAPG) had a significant inhibitory effect on phytopathogenic fungi with a minimum inhibitory concentration of 3.12–25 μg/mL. Molecular docking predicted that DAPG could bind to myosin I at two unique sites, which may be responsible to the inhibition of fungal growth. The evaluation results showed that strain ZL8 can be used to develop a dual-purpose biocontrol agents and biofertilizer. These results also provide new insights into the discovery and utilization of new resources for biocontrol agents and biolfertilizers.

Evaluation of the antagonistic potential of bacterial strains isolated from Algerian soils for the biological control of phytopathogenic fungi

Antagonistic bacteria contribute to the management of plant diseases by stimulating the natural defenses in the host and/or by ensuring direct biocontrol of the aggressors. The objective of this work was to isolate, identify and evaluate (in vitro) various Bacillus spp. for their potential to control phyopathogenic fungi. Selection of the 40 strains of Bacillus previously isolated from the soil in various areas of western Algeria was carried out by direct confrontation on the mycelial growth of four phytopathogens (Fusariumoxysporumf.splycopersici, Alternaria tenuis , Phytophthorainfestans, Ascochytapisi). This strategy involved using the antagonistic potential of microorganisms found in the plant environment in Algeria. The second part of this work consisted of the characterization and identification of tested strainsThe identification of the selected strains was carried out by biochemical tests. The results obtained showed that at the end of the fifth day, the most promising isolates showed antifungal activity and reached an inhibition rate of the mycelial growth of phytopathogenic fungi, respectively, F. oxysporumf. splycopersici 75%, A. tenuis 80%, P. infestans 83.30%, Ascochytapisi 67%. The potential antagonist of Bacillus tested in vitro by direct confrontation against 04 phytopathogenic fungi showed that all strains of Bacillus decreased fungal mycelial growth. Two strains of Bacillus B30 and B41 were found to have the most efficacy against Fusarium oxysporum f.sp. lycopersici, Alternaria tenius, Phytophtora infestans et Ascochyta pisi, with an inhibition rate of 65.25 and 72.25% respectively These results demonstrate that Bacillus sp. presenteds a potential for biological control. However, it is important to understand the mechanisms implemented by these bacteria to develop effective protection strategies.

Hololectin Interdomain Linker Determines Asparaginyl Endopeptidase-Mediated Maturation of Antifungal Hevein-Like Peptides in Oats.

Heveins and hevein-containing (hev-) lectins play important roles in stress and pathogenic responses in plants but cause health concerns in humans. Hev-hololectins contain multiple modular hev-peptide domains and are abundantly present in cereals and pseudocereals. However, it is unclear why some cereal hev-hololectins are presented as different forms of proteolytically processed proteoforms. Here we show the precursor architectures of hev-hololectins lead to different processing mechanisms to give either hololectins or hevein-like peptides. We used mass spectrometry and datamining to screen hev-peptides from common cereals, and identified from the oat plant Avena sativa nine novel hevein-like peptides, avenatide aV1–aV9. Bioinformatic analysis revealed that asparaginyl endopeptidase (AEP) can be responsible for the maturation of the highly homologous avenatides from five oat hev-hololectin precursors, each containing four tandemly repeating, hev-like avenatide domains connected by AEP-susceptible linkers with 13–16 residues in length. Further analysis of cereal hev-hololectins showed that the linker lengths provide a distinguishing feature between their cleavable and non-cleavable precursors, with the cleavables having considerably longer linkers (>13 amino acids) than the non-cleavables (<6 amino acids). A detailed study of avenatide aV1 revealed that it contains eight cysteine residues which form a structurally compact, metabolic-resistant cystine-knotted framework with a well-defined chitin-binding site. Antimicrobial assays showed that avenatide aV1 is anti-fungal and inhibits the growth of phyto-pathogenic fungi. Together, our findings of cleavable and non-cleavable hololectins found in cereals expand our knowledge to their biosynthesis and provide insights for hololectin-related health concerns in human.

High-throughput platform for yeast morphological profiling predicts the targets of bioactive compounds

Morphological profiling is an omics-based approach for predicting intracellular targets of chemical compounds in which the dose-dependent morphological changes induced by the compound are systematically compared to the morphological changes in gene-deleted cells. In this study, we developed a reliable high-throughput (HT) platform for yeast morphological profiling using drug-hypersensitive strains to minimize compound use, HT microscopy to speed up data generation and analysis, and a generalized linear model to predict targets with high reliability. We first conducted a proof-of-concept study using six compounds with known targets: bortezomib, hydroxyurea, methyl methanesulfonate, benomyl, tunicamycin, and echinocandin B. Then we applied our platform to predict the mechanism of action of a novel diferulate-derived compound, poacidiene. Morphological profiling of poacidiene implied that it affects the DNA damage response, which genetic analysis confirmed. Furthermore, we found that poacidiene inhibits the growth of phytopathogenic fungi, implying applications as an effective antifungal agent. Thus, our platform is a new whole-cell target prediction tool for drug discovery.

A Metabolomic Study of Epichloë Endophytes for Screening Antifungal Metabolites.

Epichloë endophytes, fungal endosymbionts of Pooidae grasses, are commonly utilized in forage and turf industries because they produce beneficial metabolites that enhance resistance against environmental stressors such as insect feeding and disease caused by phytopathogen infection. In pastoral agriculture, phytopathogenic diseases impact both pasture quality and animal production. Recently, bioactive endophyte strains have been reported to secrete compounds that significantly inhibit the growth of phytopathogenic fungi in vitro. A screen of previously described Epichloë-produced antifeedant and toxic alkaloids determined that the antifungal bioactivity observed is not due to the production of these known metabolites, and so there is a need for methods to identify new bioactive metabolites. The process described here is applicable more generally for the identification of antifungals in new endophytes. This study aims to characterize the fungicidal potential of novel, ‘animal friendly’ Epichloë endophyte strains NEA12 and NEA23 that exhibit strong antifungal activity using an in vitro assay. Bioassay-guided fractionation, followed by metabolite analysis, identified 61 metabolites that, either singly or in combination, are responsible for the observed bioactivity. Analysis of the perennial ryegrass-endophyte symbiota confirmed that NEA12 and NEA23 produce the prospective antifungal metabolites in symbiotic association and thus are candidates for compounds that promote disease resistance in planta. The “known unknown” suite of antifungal metabolites identified in this study are potential biomarkers for the selection of strains that enhance pasture and turf production through better disease control.

Biocontrol of Fusarium spp. by soil surface fungi from Mt. Isarog, Camarines Sur

The pathogenic strains of Fusarium spp. wilt entire hectares of agriculturally important crops, and biological control is the most advantageous method to halt this problem. In this study, fourteen soil surface fungi were isolated using serial dilution and initial inoculation in synthetic nutrient-poor agar (SNA), Czapek Dox agar (CDA), and malt extract agar (MEA). The soilborne fungal isolates were morphologically identified into four genera: Aspergillus, Curvularia, Dictyuchus, Trichoderma, while two were identified as mycelia sterilia. We performed dual culture and best inoculation method to test the biocontrol activity of the 14 soil surface fungi against Fusarium verticillioides, Fusarium moniliforme, and Fusarium sp. Both methods revealed that soil surface fungi could inhibit the growth of phytopathogenic fungi. Aspergillus sp. 3 inhibited the growth of three pathogenic fungi when planted first in best inoculation, while Trichoderma sp. inhibited the growth of Fusarium sp. in both methods, and F. verticillioides when planted first in the best inoculation method.

The expediency of using a plant protection system using the microbiological fungicide BisolbiSan, W in the cultivation of winter wheat in the Southern natural and agricultural zone of the Rostov region

The authors analyzed the biological effectiveness of the integrated plant protection system formed when the microbiological fungicide BisolbiSan, Zh was included in the classical protection scheme adopted in the farms of the Rostov region. The biological effectiveness of the integrated protection system, including the fungicide BisolbiSan, was analyzed, the impact of the studied protection system on the yield, the quality of the grain obtained, the phytosanitary condition of the crop during the growing season on winter wheat crops of the variety Nakhodka with the use of a plant protection system, including the fungicide BisolbiSan, Zh. The fungicide BisolbiSan, containing a culture of rhizospheric bacteria Bacillus subtilis strain H-13, suppresses the germination of spores and mycelium growth of phytopathogenic fungi due to the multilateral action of bacterial metabolites, without causing the formation of resistance in pathogens. It was found that the protection system used practically does not cause a decrease in grain quality — in terms of the average protein and gluten content, the grain at the experimental site even slightly exceeds the grain obtained from the control site by 16.88% and 27.8%. With the cost of winter wheat grain of 1100 rubles/kg, an increase in the yield in the experiment of 3.8 kg/ha in relation to control and the cost of an experimental protection system in the amount of 3,357 rubles/ha, revenue amounted to 823 rubles/ha.