Fungal Reproduction Research Articles

Bidirectional interactions between Grosmannia abietina and hybrid white spruce: Pathogenicity, monoterpene defense responses, and fungal growth and reproduction

Bark beetle-vectored phytopathogenic fungi can play critical roles in how beetle outbreaks affect the health of forest trees. However, trees can defend themselves against fungal infection. How Grosmannia abietina, a symbiotic fungus of spruce beetle (Dendroctonus rufipennis), affects the health of mature hybrid white spruce (Picea engelmannii x glauca) and is in turn affected by the tree's defenses are unknown. We conducted field inoculations of this spruce to study the degree of pathogenicity of G. abietina, characterized the trees' resulting defensive monoterpene responses, and assessed monoterpene effects on fungal growth and reproduction in laboratory bioassays. Our results indicated that G. abietina is phytopathogenic to hybrid white spruce, which induced monoterpenes in response to infection. Dominant induced monoterpenes generally inhibited fungal growth but stimulated spore production. These findings provide insights into the bidirectional effects between spruce beetle-vectored fungi and host trees, highlighting the complex role of monoterpenes in modulating fungal activities.

Transcriptome Analysis Reveals the Effect of Oyster Mushroom Spherical Virus Infection in Pleurotus ostreatus.

Oyster mushroom spherical virus (OMSV) is a mycovirus that inhibits mycelial growth, induces malformation symptoms, and decreases the yield of fruiting bodies in Pleurotus ostreatus. However, the pathogenic mechanism of OMSV infection in P. ostreatus is poorly understood. In this study, RNA sequencing (RNA-seq) was conducted, identifying 354 differentially expressed genes (DEGs) in the mycelium of P. ostreatus during OMSV infection. Verifying the RNA-seq data through quantitative real-time polymerase chain reaction on 15 DEGs confirmed the consistency of gene expression trends. Both Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses highlighted the pivotal role of primary metabolic pathways in OMSV infection. Additionally, significant changes were noted in the gene expression levels of carbohydrate-active enzymes (CAZymes), which are crucial for providing the carbohydrates needed for fungal growth, development, and reproduction by degrading renewable lignocellulose. The activities of carboxymethyl cellulase, laccase, and amylase decreased, whereas chitinase activity increased, suggesting a potential mechanism by which OMSV influenced mycelial growth through modulating CAZyme activities. Therefore, this study provided insights into the pathogenic mechanisms triggered by OMSV in P. ostreatus.

Response of a simulated aquatic fungal community to nanoplastics exposure and functional consequence on leaf decomposition

Nanoplastics pose a potential threat to a wide variety of aquatic organisms. Despite the awareness of this existing hazard, the impact of nanoplastics on natural fungal communities remains a research gap. In this study, five dominant fungi species, isolated from a stream ecosystem, were used to explore the effects of different nano-polystyrene (nano-PS) particles concentrations on a simulated fungal community. Specifically, the evaluation was conducted regarding the fungal growth, reproductivity, structural composition, and ecological function in leaf litter decomposition. A 15-day exposure experiment showed that 100 μg/L nano-PS significantly reduced the microcosm pH. The extracellular enzyme activities of β-glucosidase, leucine-aminopeptidase, and peroxidase were significantly promoted by nano-PS exposure for 5 days or 15 days. Total sporulation rate significantly decreased after the 15-day exposure to 1 and 100 μg/L nano-PS and significantly increased under 10 μg/L nano-PS. In contrast, nano-PS concentrations had no effects on fungal biomass. In addition, the reduced relative abundance of Geotrichum candidum lowered its contribution to leaf decomposition, resulting in a decreased litter decomposition rate of a 24.5–27.9 % after exposure. This suggests that 1–100 μg/L nano-PS inhibited leaf decomposition by inhibiting fungal reproduction and reducing the contribution of specific fungal species. In addition, the findings highlight the importance of exploring the potential mechanisms of the interaction between nanoplastics and fungal species.

Fungal identity mediates the impacts of multiple stressors on freshwater ecosystems

Predicting how multiple anthropogenic stressors affect natural ecosystems is a major challenge in ecology. Freshwater ecosystems are threatened worldwide by multiple co-occurring stressors, which can affect aquatic biodiversity, ecosystem functioning and human wellbeing. In stream ecosystems, aquatic fungi play a crucial role in global biogeochemical cycles and food web dynamics, therefore, assessing the functional consequences of fungal biodiversity loss under multiple stressors is crucial. Here, a microcosm approach was used to investigate the effects of multiple stressors (increased temperature and nutrients, drying, and biodiversity loss) on three ecosystem processes: organic matter decomposition, fungal reproduction, and fungal biomass accrual. Net effects of stressors were antagonistic for organic matter decomposition, but additive for fungal reproduction and biomass accrual. Net effects of biodiversity were mainly positive for all processes, even under stress, demonstrating that diversity assures the maintenance of ecosystem processes. Fungal species displayed distinct contributions to each ecosystem process. Furthermore, species with negligible contributions under control conditions changed their role under stress, either enhancing or impairing the communities' performance, emphasizing the importance of fungal species identity. Our study highlights that distinct fungal species have different sensitivities to environmental variability and have different influence on the overall performance of the community. Therefore, preserving high fungal diversity is crucial to maintain fungal species with key ecosystem functions within aquatic communities in face of environmental change.

Effects of Light on the Fruiting Body Color and Differentially Expressed Genes in Flammulina velutipes.

Light plays vital roles in fungal growth, development, reproduction, and pigmentation. In Flammulina velutipes, the color of the fruiting body exhibits distinct changes in response to light; however, the underlying molecular mechanisms remain unknown. Therefore, in this study, we aimed to analyze the F. velutipes transcriptome under red, green, and blue light-emitting diode (LED) lights to identify the key genes affecting the light response and fruiting body color in this fungus. Additionally, we conducted protein-protein interaction (PPI) network analysis of the previously reported fruiting body color-related gene, Fvpal1, to identify the hub genes. Phenotypic analysis revealed that fruiting bodies exposed to green and blue lights were darker than those untreated or exposed to red light, with the color intensifying more after 48 h of exposure to blue light compared to that after 24 h of exposure. Differentially expressed gene (DEG) analyses of all light treatments for 24 h revealed that the numbers of DEGs were 17, 74, and 257 under red, green, and blue lights, respectively. Subsequently, functional enrichment analysis was conducted of the DEGs identified under green and blue lights, which influenced the color of F. velutipes. In total, 103 of 168 downregulated DEGs under blue and green lights were included in the enrichment analysis. Among the DEGs enriched under both green and blue light treatments, four genes were related to monooxygenases, with three genes annotated as cytochrome P450s that are crucial for various metabolic processes in fungi. PPI network analysis of Fvpal1 revealed associations with 11 genes, among which the expression of one gene, pyridoxal-dependent decarboxylase, was upregulated in F. velutipes exposed to blue light. These findings contribute to our understanding of the molecular mechanisms involved in the fruiting body color changes in response to light and offer potential molecular markers for further exploration of light-mediated regulatory pathways.

Assessing the response of an urban stream ecosystem to salinization under different flow regimes

Urban streams are exposed to a variety of anthropogenic stressors. Freshwater salinization is a key stressor in these ecosystems that is predicted to be further exacerbated by climate change, which causes simultaneous changes in flow parameters, potentially resulting in non-additive effects on aquatic ecosystems. However, the effects of salinization and flow velocity on urban streams are still poorly understood as multiple-stressor experiments are often conducted at pristine rather than urban sites. Therefore, we conducted a mesocosm experiment at the Boye River, a recently restored stream located in a highly urbanized area in Western Germany, and applied recurrent pulses of salinity along a gradient (NaCl, 9 h daily of +0 to +2.5 mS/cm) in combination with normal and reduced current velocities (20 cm/s vs. 10 cm/s). Using a comprehensive assessment across multiple organism groups (macroinvertebrates, eukaryotic algae, fungi, parasites) and ecosystem functions (primary production, organic-matter decomposition), we show that flow velocity reduction has a pervasive impact, causing community shifts for almost all assessed organism groups (except fungi) and inhibiting organic-matter decomposition. Salinization affected only dynamic components of community assembly by enhancing invertebrate emigration via drift and reducing fungal reproduction. We caution that the comparatively small impact of salt in our study can be due to legacy effects from past salt pollution by coal mining activities >30 years ago. Nevertheless, our results suggest that urban stream management should prioritize the continuity of a minimum discharge to maintain ecosystem integrity. Our study exemplifies a holistic approach for the assessment of multiple-stressor impacts on streams, which is needed to inform the establishment of a salinity threshold above which mitigation actions must be taken.

Unraveling the multifaceted effects of climatic factors on mountain pine beetle and its interaction with fungal symbionts.

Mountain pine beetles (MPBs) pose a substantial threat to North American pine forests, causing extensive tree mortality over large areas. Their tree-killing ability is closely linked to mass aggregation on host trees triggered via pheromones and dependence on their symbiotic fungi. However, the influence of a changing climate on the biology of MPBs and their co-evolved interactions with their fungal symbionts remains uncertain. To investigate this, male and female pairs of beetles were introduced into freshly cut logs from lodgepole pine trees and placed in controlled climate chambers with manipulated environmental conditions, including two levels of CO2 (ambient vs. 1000 ppm), O3 (ambient vs. 100 ppb) and humidity (33% vs. 65%). The beetle-infested logs were left in these chambers for 1 month and then returned to ambient conditions until brood emergence. Emerging broods were collected for further analysis. Additionally, three species of fungal symbionts (Grosmannia clavigera, Ophiostoma montium and Leptographium longiclavatum) were subjected to the same CO2 , O3 and humidity conditions for 5 days. Lower humidity promoted MPB reproduction and fungal growth. Elevated CO2 accelerated larval growth and emergence while improving brood pheromone production. Elevated O3 had a negative impact on MPB reproduction and brood fitness while improving its immune responses to an entomopathogenic fungus (Beauveria bassiana). It also inhibited fungal growth and reproduction, whereas elevated CO2 had varied (positive or negative) effects on fungal growth and ergosterol (proxy to fungal mass) production depending on the fungal species. Together, these findings suggest that climate change can potentially alter the interactions between MPBs and their fungal symbionts, highlighting the importance of understanding how climate change affects forest pests and their symbiotic relationships to develop effective management strategies in the future.

Utilization of Yeasts in Promoting Plant Growth in Acidic Soil – A Review

The ecosystem's biodiversity and soil microorganisms are impacted by the increasing use of synthetic fertilizers and pesticides, which causes soil acidity and limits the sustainability of agricultural output. The majority of microbial functions in acidic soil are inhibited because of decreasing nutrient cycling and organic matter decomposition as well as diminishing bacterial and fungal growth and reproduction. In light of these growing concerns, the use of microorganisms as bio fertilizers is a recommended as alternative agricultural practice. Recent times have brought about a change in the paucity of study on yeasts and their ability to safely boost plant growth. Numerous works on bacteria have been made available. The primary objective of the study is to highlight the widespread application of yeasts in sustainable agricultural practices to promote plant growth in acidic soils. All of the advantages that yeasts provide may contribute to the growth of plants. Therefore, a thorough investigation into yeasts may be fruitful and offer a sustainable means of boosting agricultural yields that are necessary in acidic soil.

Deazaflavin metabolite produced by endosymbiotic bacteria controls fungal host reproduction.

The endosymbiosis between the pathogenic fungus Rhizopus microsporus and the toxin-producing bacterium Mycetohabitans rhizoxinica represents a unique example of host control by an endosymbiont. Fungal sporulation strictly depends on the presence of endosymbionts as well as bacterially produced secondary metabolites. However, an influence of primary metabolites on host control remained unexplored. Recently, we discovered that M. rhizoxinica produces FO and 3PG-F420, a derivative of the specialized redox cofactor F420. Whether FO/3PG-F420 plays a role in the symbiosis has yet to be investigated. Here, we report that FO, the precursor of 3PG-F420, is essential to the establishment of a stable symbiosis. Bioinformatic analysis revealed that the genetic inventory to produce cofactor 3PG-F420 is conserved in the genomes of eight endofungal Mycetohabitans strains. By developing a CRISPR/Cas-assisted base editing strategy for M. rhizoxinica, we generated mutant strains deficient in 3PG-F420 (M. rhizoxinica ΔcofC) and in both FO and 3PG-F420 (M. rhizoxinica ΔfbiC). Co-culture experiments demonstrated that the sporulating phenotype of apo-symbiotic R. microsporus is maintained upon reinfection with wild-type M. rhizoxinica or M. rhizoxinica ΔcofC. In contrast, R. microsporus is unable to sporulate when co-cultivated with M. rhizoxinica ΔfbiC, even though the fungus was observed by super-resolution fluorescence microscopy to be successfully colonized. Genetic and chemical complementation of the FO deficiency of M. rhizoxinica ΔfbiC led to restoration of fungal sporulation, signifying that FO is indispensable for establishing a functional symbiosis. Even though FO is known for its light-harvesting properties, our data illustrate an important role of FO in inter-kingdom communication.

Structure of the Mating-Type Genes and Mating Systems of Verpa bohemica and Verpa conica (Ascomycota, Pezizomycotina).

Verpa spp. are potentially important economic fungi within Morchellaceae. However, fundamental research on their mating systems, the key aspects of their life cycle, remains scarce. Fungal sexual reproduction is chiefly governed by mating-type genes, where the configuration of these genes plays a pivotal role in facilitating the reproductive process. For this study, de novo assembly methodologies based on genomic data from Verpa spp. were employed to extract precise information on the mating-type genes, which were then precisely identified in silico and by amplifying their single-ascospore populations using MAT-specific primers. The results suggest that the MAT loci of the three tested strains of V. bohemica encompassed both the MAT1-1-1 and MAT1-2-1 genes, implying homothallism. On the other hand, amongst the three V. conica isolates, only the MAT1-1-1 or MAT1-2-1 genes were present in their MAT loci, suggesting that V. conica is heterothallic. Moreover, bioinformatic analysis reveals that the three tested V. bohemica strains and one V. conica No. 21110 strain include a MAT1-1-10 gene in their MAT loci, while the other two V. conica strains contained MAT1-1-11, exhibiting high amino acid identities with those from corresponding Morchella species. In addition, MEME analysis shows that a total of 17 conserved protein motifs are present among the MAT1-1-10 encoded protein, while the MAT1-1-11 protein contained 10. Finally, the mating type genes were successfully amplified in corresponding single-ascospore populations of V. bohemica and V. conica, further confirming their life-cycle type. This is the first report on the mating-type genes and mating systems of Verpa spp., and the presented results are expected to benefit further exploitation of these potentially important economic fungi.

Morphological and ultrastructural changes in fungal agents after LASER application.

Onychomycosis is a fungal nail infection of difficult treatment due to the fungal survival capacity and reduced number of effective therapies. The present study aimed to isolate fungal agents that cause onychomycosis in immunocompetent patients and evaluate how LASER treatments affect the growth and ultrastructure of isolates. In total, 21 patients with positive direct microscopic examination (DME) for onychomycosis had nail samples collected for cultivation and phenotypic identification of microorganisms. From these patients, 12 underwent LASER treatment, divided in Group 1 (n = 5) treated with Nd: YAG 1,064 nm, and Group 2 (n = 7) treated with Nd: YAG 1,064 nm + Er: YAG 2,940 nm + topical isoconazole. Transmission Electron Microscopy (TEM) was performed to evaluate ultrastructural changes after treatment. DME, cultivation, and phenotypic identification showed that the most identified fungus was Trichophyton rubrum spp. After LASER therapy, sample cultivation showed alterations in the fungal morphology with reduction of hyphae, conidia, and reproductive structures. Alterations in fungal cell wall structure, cytoplasm density, and organelles were observed by TEM. LASER irradiation causes changes in the fungal cells, especially in the number of hyphae and the presence of conidia. In addition, it affects fungal growth and reproduction capacity, which interferes with their infection ability and virulence.

Inner cyclic cooling aeration on stored maize in large commercial warehouses in Northeast China

ABSTRACT Controlling grain temperatures is the main approach employed in large commercial warehouses to maintain quality and prevent infestation by insects and fungi. Large commercial warehouses in northeast China have been utilizing inner cyclic cooling aeration (ICCA), a newly developed method for managing summertime temperatures, haphazardly and without tight standards. We utilized a homemade detector to track the temperature, humidity, and CO2 concentrations of maize that was held for four years under ICCA treatment. The monitoring occurred every week, specifically from July 1st to September 30th. In addition, we conducted weekly tests to determine the moisture content (MC) and free fatty acids (FFA) of the stored maize samples. Without the use of ICCA, the average temperature of the stored maize above a depth of 3.5 m ranged from 20°C to 28°C, and the relative humidity (RH) in the headspace was typically higher than 75%. However, when ICCA was applied, the average temperature could be maintained at 22°C, and the RH was below 65% for most of the time. In the first year, the MC of the stored maize at a depth of 1.0 m experienced a loss of approximately 0.5%. However, for one year, there was no significant loss in the MC of the maize stored at the same depth. Furthermore, the FFA in the stored maize at a depth of 1 m increased by 1–5 mg KOH/100 g. The use of ICCA effectively controls the temperature and RH in the stored maize, reducing the risk of insect and fungal reproduction.

Deciphering the role of fungi in post-fire succession in Canada's Great Lakes–St. Lawrence forest region

Fungi are important drivers of forest health, as well as culturally important for many Indigenous communities. In Canada, increasingly intense and frequent wildfires affect fungal substrates and habitats, environmental conditions, and physiological responses of hosts with which fungi may interact. In Ontario, aggressive fire suppression raises the question of how fungal regeneration, and taxonomic compositions, may be affected when fires do appear on the landscape. This study investigates the fungal regrowth post-fire above and below-ground and the role fungal species play in post fire ecological succession in Southeastern Ontario. The study sites are two black oak savannas in restoration, previously prescribed a burn (Northumberland County, 2022 and 2023), and a recent wildfire burned mixed deciduous forest (Centennial Lake, 2023). We collected fruiting body and soil samples for fungal identification via observational and DNA methods. Above ground vegetation assays were made at 9 burned plots within these three sites and another 8 adjacent unburned (control) plots. We extracted soil DNA and will amplify fungal ITS2 amplicons by PCR. Then, we will sequence the amplified DNA using MiSeq to compare burned and unburned soil fungi. Lastly, we will use statistical methods to differentiate effects from fire and soil texture and type in burned and control plots. Thus far, we found that Pyropyxis rubra, a pyrophilous ascomycete fungus, is extremely abundant just weeks after the lightning-induced fire at Centennial Lake. Our combined observational and quantitative descriptions of above-and below ground soil fungi provide a deeper understanding of how fire affects species composition, fungal reproduction, and population dynamics in Ontario. This research may help inform other successional processes, and fungal harvesting of culturally important species.

The epigenetic regulator Set9 harmonizes fungal development, secondary metabolism, and colonization capacity of Aspergillus flavus

As a widely distributed food-borne pathogenic fungus, Aspergillus flavus and its secondary metabolites, mainly aflatoxin B1 (AFB1), pose a great danger to humans. It is urgent to reveal the complex regulatory network of toxigenic and virulence of this fungus. The bio-function of Set9, a SET-domain-containing histone methyltransferase, is still unknown in A. flavus. By genetic engineering means, this study revealed that, through catalyzing H4K20me2 and -me3, Set9 is involved in fungal growth, reproduction, and mycotoxin production via the orthodox regulation pathway, and regulates fungal colonization on crop kernels through adjusting fungal sensitivity reactions to oxidation stress and cell wall integrity stress. Further domain deletion and point mutation inferred that the SET domain is the core element in catalyzing H4K20 methylation, and D200 site of the domain is the key amino acid in the active center of the methyltransferase. Combined with RNA-seq analysis, this study revealed that Set9 regulates the aflatoxin gene cluster by the AflR-like protein (ALP), other than traditional AflR. This study revealed the epigenetic regulation mechanism of fungal morphogenesis, secondary metabolism, and pathogenicity of A. flavus mediated by the H4K20-methyltransferase Set9, which might provide a potential new target for early prevention of contamination of A. flavus and its deadly mycotoxins.

Potential pathways and genes expressed in Chrysanthemum in response to early fusarium oxysporum infection

BackgroundChrysanthemum Fusarium wilt is a common fungal disease caused by Fusarium oxysporum, which causes continuous cropping obstacles and huge losses to the chrysanthemum industry. The defense mechanism of chrysanthemum against F. oxysporum remains unclear, especially during the early stages of the disease. Therefore, in the present study, we analyzed chrysanthemum ‘Jinba’ samples inoculated with F. oxysporum at 0, 3, and 72 h using RNA-seq.ResultsThe results revealed that 7985 differentially expressed genes (DEGs) were co-expressed at 3 and 72 h after F. oxysporum infection. We analyzed the identified DEGs using Kyoto Encyclopedia of Genes and Genomes and Gene Ontology. The DEGs were primarily enriched in “Plant pathogen interaction”, “MAPK signaling pathway”, “Starch and sucrose metabolism”, and “Biosynthesis of secondary metabolites”. Genes related to the synthesis of secondary metabolites were upregulated in chrysanthemum early during the inoculation period. Furthermore, peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase enzymes were consistently produced to accumulate large amounts of phenolic compounds to resist F. oxysporum infection. Additionally, genes related to the proline metabolic pathway were upregulated, and proline levels accumulated within 72 h, regulating osmotic balance in chrysanthemum. Notably, the soluble sugar content in chrysanthemum decreased early during the inoculation period; we speculate that this is a self-protective mechanism of chrysanthemums for inhibiting fungal reproduction by reducing the sugar content in vivo. In the meantime, we screened for transcription factors that respond to F. oxysporum at an early stage and analyzed the relationship between WRKY and DEGs in the “Plant-pathogen interaction” pathway. We screened a key WRKY as a research target for subsequent experiments.ConclusionThis study revealed the relevant physiological responses and gene expression changes in chrysanthemum in response to F. oxysporum infection, and provided a relevant candidate gene pool for subsequent studies on chrysanthemum Fusarium wilt.

Design, Synthesis, In Vitro Antifungal Activity and Mechanism Study of the Novel 4-Substituted Mandelic Acid Derivatives.

Plant diseases caused by phytopathogenic fungi are a serious threat in the process of crop production and cause large economic losses to global agriculture. To obtain high-antifungal-activity compounds with novel action mechanisms, a series of 4-substituted mandelic acid derivatives containing a 1,3,4-oxadiazole moiety were designed and synthesized. In vitro bioassay results revealed that some compounds exhibited excellent activity against the tested fungi. Among them, the EC50 values of E13 against Gibberella saubinetii (G. saubinetii), E6 against Verticillium dahlia (V. dahlia), and E18 against Sclerotinia sclerotiorum (S. sclerotiorum) were 20.4, 12.7, and 8.0 mg/L, respectively, which were highly superior to that of the commercialized fungicide mandipropamid. The morphological studies of G. saubinetii with a fluorescence microscope (FM) and scanning electron microscope (SEM) indicated that E13 broke the surface of the hyphae and destroyed cell membrane integrity with increased concentration, thereby inhibiting fungal reproduction. Further cytoplasmic content leakage determination results showed a dramatic increase of the nucleic acid and protein concentrations in mycelia with E13 treatment, which also indicated that the title compound E13 could destroy cell membrane integrity and affect the growth of fungi. These results provide important information for further study of the mechanism of action of mandelic acid derivatives and their structural derivatization.

Comparative analysis of infection process in Upland cottons differing in resistance to Fusarium wilt caused byFusarium oxysporumf. sp.vasinfectumrace 4

AbstractFusarium wilt (Fusarium oxysporumf. sp.vasinfectumrace 4, FOV4) in cotton is an early season soil‐borne vascular disease including seedling wilt and death. Its infection process in Upland cotton is currently unknown. This study compared the infection process among three Upland cotton cultivars (Gossypium hirsutum) using a confocal microscope. Seedlings were grown in a hydroponic system to the two‐true leaf stage and inoculated with a virulent local FOV4 isolate. Based on the infection process, the resistant cultivar FM 2334GLT was divided into resistant (R) and susceptible (S) groups. The susceptible PHY 725 RF and FM 2334GLT(S) had the highest numbers of conidia attached and germinated on the root surface, followed by susceptible Acala 1517‐08. FM 2334GLT(R) had the lowest numbers. Hyphae penetration and colonization inside the root followed a similar trend. In PHY 725 RF, FM 2334GLT(S), and Acala 1517‐08, hyphae started to penetrate into epidermal cells at 2 days post inoculation (dpi), spread in the cortex intercellularly and intracellularly at 3–5 dpi, and entered the xylem vessels at 7 dpi, followed by colonization at 11–15 dpi. FM 2334GLT(R) had the lowest numbers of penetrating hyphae inside the root, with no apparent hyphae observed in the xylem. This study demonstrated that FM 2334GLT(R) had delayed infection, reduced fungal growth and reproduction, and prevented the FOV4 fungus from invading the xylem. The resistance in FM 2334GLT(R) was similar to that in Pima PHY 841 RF but with fewer hyphae in the cortex, suggesting possible different resistant mechanisms.

Chemotypes of Species of the Genus Thymus L. in Carpathians Region of Ukraine—Their Essential Oil Qualitative and Quantitative Characteristics and Antimicrobial Activity

The study of the R&D in this paper is to determine the range of essential oils (EOs) in the raw materials of species of the genus Thymus of the natural flora in the Carpathian region and their antimicrobial activity. It was found that the component range of EO in species of the genus Thymus depends on the microclimatic conditions of the population. The range of essential oils in the raw material of Th. Serpyllum and Th. Pulegoides is 7–9 mL and Th. Marschallianus is 3.5 mL. The research found that the plants Th. Serpyllum and Th. Pulegoides that grow in sunny habitats have an aromatic mono- and bicyclic monoterpenoid chemotype (K/α-T-neol/ G/p-C/B), with total dominance of carvacrol and p-cymene. The populations of Th. Serpyllum, which grow on the edges of sparse pine forests, and populations of Th. Pullegioide, with denser plant cover and which grow in meadows, have an acyclic and bicyclic monoterpene chemotype (G/α-T-neol/B/K). Plants that grow in the communities of meadow-steppe vegetation have the following chemotypes: Th. Serpyllum—L/K/G with 63% of linalool, Th. Pullegioides—G/α-T-neol/L/B, and Th. Marschallianus—α-T-neol/K/L/α-T-nen/G/B. Of these, the dominant chemotypes are α-terpineol and carvacrol (28:6.5%). A wide spectrum of antimicrobial activity was registered in samples of Th. Pullegoides and Th. Serpyllum that have an aromatic-monoterpenoid chemotype. Essential oils of Th. Pullegoides were dominated by carvacrol, and p-cymene had the highest fungicidal action (41.00 ± 1.0%). Plant populations of Th. Pullegoides and Th. Serpyllum with the aromatic-monoterpenoid chemotype are suggested by R&D to be of use in the pharmaceutical industry. They have high contents of natural components, which are effective in a wide spectrum of antimicrobial activity. The EO of Th. Marschallianus had the lowest influence on the inhibition of bacterial and fungal reproduction.

Growth Intensity of Trichoderma Viride at Different Doses and Sources of Copper in the Medium

The biological properties of Trichoderma Viride fungi allow them to be effectively used in the technologies of crop waste disposal, production of organic, environmentally friendly fertilisers, and prevention of soil diseases of plants. The growth and development of these fungi depend on a number of trace elements that are found in the medium. Copper is of great importance among trace elements. The establishment of the ability to use copper as a stimulator of biomass accumulation of Trichoderma Viride fungi is of scientific and practical interest for national economic needs, which indicates the relevance of the study. The purpose of the study is to establish the effectiveness of the effect of various copper compounds on the growth and development of Trichoderma Viride. To investigate the effect of the metal-biotic on the growth of microorganisms, 0.5 to 10.0 mg/100 cm3 of the element in the form of copper sulphate, mixed ligand complex and copper glycinate were added to the medium with potato dextrose agar (PDA). In the control variant, the element was not added to the nutrient medium. The media were inoculated with the Viridin preparation. Trichoderma Viride growth was recorded on days 4 and 7 of the experiment. It has been experimentally established that the fungal population is affected by the content and source of copper in the medium. It was found that the presence of a biotic metal in the medium in mineral or chelated form is up to 1.0 mg/100 cm3 stimulates the build-up of fungal biomass. It was proved that on the 4th day of cultivation for the introduction of copper into the medium in the amount of 1.0 mg/100 cm3 in the mixed-ligand form, the population of Trichoderma Viride increased by 75.0%. On the 7th day, the increase in the number of fungal cells was 58.3%. It was found that with the introduction in the medium of more than 5.0 mg/100 cm3 copper in any form, the population growth of Trichoderma Viride fungi decreased. The higher the copper content in the medium, the greater the inhibition of fungal cell reproduction. It was generalised that comparing the action of the mixed ligand complex copper, copper glycinate, and copper sulphate, it was found that the latter compound is the most toxic against Trichoderma Viride

Historic and charming <italic>Monascus</italic> spp.

<p indent="0mm"><italic>Monascus</italic> species are well-known as fermentation strains in food and pharmaceutical industries in China. <italic>Monascus</italic> spp. have a long application history for more than <sc>2000 years.</sc> Red mold rice (RMR), also known as anka and Hongqu in China, is the fermented product of steamed rice inoculated with certain <italic>Monascus</italic> strains. Nowadays, RMR and its related products have been extensively applied in food and medicine industries. In these RMR products, <italic>Monascus</italic> strains produce two kinds of the most well-known secondary metabolites (SMs) <italic>Monascus</italic> pigments (MPs) and monacolin K (MK). MPs have been employed as natural food colorant in Southeast Asia over one thousand years. MK (also known as lovastatin), an anticholesterol compound, has been developed to be a hypolipidemic drug and food supplements. Today, RMR and its relative products mainly yielded in China are not only applied in Southeast Asia, but also exported to Europe and America. It is estimated that more than one billion people, around the world, eat RMR and other relative products in their daily life. Therefore, <italic>Monascus</italic> species are considered as one of the historic and charming fermentation strains in China. Theoretical researches and product development of <italic>Monascus</italic> strains have attracted wide attention and made fruitful scientific achievements, especially in recent <sc>30 years.</sc> In-depth studies regarding RMR have revealed that <italic>Monascus</italic> spp. not only produce beneficial SMs, MPs and MK, but also a mycotoxin citrinin (CIT). A substantial amount of researches has been successfully made to elucidate the biosynthetic pathways of these SMs and their regulation mechanism. These achievements not only serve as models of fungal SMs biosynthesis, but also provide a roadmap for metabolic engineering and synthetic biology towards the selective production of the more valuable components. Furthermore, <italic>Monascus</italic> spp. also are unique objects for researching fungal reproduction regulation and magnetic and/or light responses because <italic>Monascus</italic> spp. are found to be significantly different from the known filamentous fungi in these two fields. The progress on reproduction regulation of <italic>Monascus</italic> spp. revealed that the well-established conidiation central regulation in <italic>Aspergillus</italic> species is not applicable in their <italic>Monascus</italic> relatives. On the other hand, <italic>M</italic>.<italic> ruber</italic> M7 genome contains one red-light and two green-light receptors, but not any blue-light receptor ortholog is present in<italic> M</italic>.<italic> ruber </italic>M7 and other <italic>Monascus</italic> species, indicating a biologically significant difference between <italic>Monascus</italic> species and other filamentous fungi. Because of the unique reproduction mechanism, light and magnetic response and abundant SMs biosynthesis of <italic>Monascus</italic> spp., it is expected to enrich the theoretical understanding of filamentous fungi and even the biological world through further research on <italic>Monascus</italic> spp. Therefore, it demonstrates a great potential for developing <italic>Monascus</italic> spp. into a model microorganism. The key discussions and future prospects are also proposed from the aspects of faced challenge on <italic>Monascus</italic> spp. investigation and their products development.