Root Rot Fungus Research Articles

Geographical variations, prevalence, and molecular dynamics of fastidious phloem-limited pathogens infecting sugar beet across Central Europe.

In Europe, two fastidious phloem-limited pathogens, 'Candidatus Phytoplasma solani' (16SrXII-A) and 'Candidatus Arsenophonus phytopathogenicus', are associated with rubbery taproot disease (RTD) and syndrome basses richesses (SBR) of sugar beet, respectively. Both diseases can significantly reduce yield, especially when accompanied by root rot fungi. This study investigates the presence, geographic distribution and genetic traits of fastidious pathogens and the accompanying fungus, Macrophomina phaseolina, found on sugar beet across four geographically separated plains spanning seven countries in Central Europe. The survey revealed variable incidences of symptoms linked to these fastidious pathogens in the Pannonian and Wallachian Plains, sporadic occurrence in the North European Plain, and no symptomatic sugar beet in the Bohemian Plain. Molecular analyses unveiled the occurrence of both 'Ca. P. solani' and 'Ca. A. phytopathogenicus' throughout Central Europe, with a predominance of the phytoplasma. These fastidious pathogens were detected in all six countries surveyed within the Pannonian and Wallachian Plains, with only a limited presence of various phytoplasmas was found in the North European Plain, while no fastidious pathogens were detected in Bohemia, aligning with observed symptoms. While 16S rDNA sequences of 'Ca. P. solani' remained highly conserved, multi-locus characterization of two more variable loci (tuf and stamp) unveiled distinct variability patterns across the plains. Notably, the surprising lack of variability of tuf and stamp loci within Central Europe, particularly the Pannonian Plain, contrasted their high variability in Eastern and Western Europe, corresponding to epidemic and sporadic occurrence, respectively. The current study provides valuable insights into the genetic dynamics of 'Ca. P. solani' in Central Europe, and novel findings of the presence of 'Ca. A. phytopathogenicus' in five countries (Slovakia, Czech Republic, Austria, Serbia, and Romania) and M. phaseolina in sugar beet in Slovakia. These findings emphasize the need for further investigation of vector-pathogen(s)-plant host interactions and ecological drivers of disease outbreaks.

First report of root rot of strawberry caused by Fusarium cugenangense, a member of the F. oxysporum species complex, in Tennessee, USA.

Strawberry (Fragaria × ananassa Duch) in Tennessee is cultivated on plastic mulched beds annually, and production is limited primarily by multiple oomycete and fungal root rot pathogens that result in reduced vigor and black root rot disease symptoms. In early June 2018, plants (cv. Chandler) with reduced shoot vigor and size, and black, necrotic stunted roots were collected from Rhea County, TN. Roots and crowns of 10 plants were cut into 1-3 cm pieces and surface sterilized with 0.6% NaOCl, followed by 70% ethanol for 1 min each, and plated on water agar. White mycelia produced after 3 days were transferred to potato dextrose agar amended with 10 mg/liter rifampicin. After 10 days, fungal colonies were light purple on the surface and dark purple on the colony underside, later developing blue-black pigmentation on the underside. Microconidia on carnation leaf agar were ovoid to ellipsoid, aseptate or septate and 8.0 to 24.2 (13.7) × 3.0 to 4.5 (3.8) μm in size, macroconidia were 3 to 5 septate and falcate to almost straight and 33.7 to 52.8 (44.4) × 4.0 to 5.5 (4.9) μm in size (n=80); both conidia were produced on monophialides. Chlamydospores were globose and subglobose, formed terminally and intercalary on aerial, submerged, and surface mycelium, singly or in pairs and were abundantly produced in sucrose broth and on synthetic nutrient-poor agar (SNA) (diam. 7.6 μm). Morphology was consistent with Fusarium oxysporum (Leslie and Summerell, 2006) and F. cugenangense, a member of the F. oxysporum species complex, as described by Maryani et al. (2019). Fungal mycelia were used for PCR (Phire Plant Direct PCR Master Mix, Thermo Scientific, CA) and the translational elongation factor 1-α (EF1α) region was amplified with primers EF-1/EF-2 (O'Donnell et al., 1998), internal transcribed spacer (ITS) regions amplified with primers ITS1/ITS2 (White et al. 1990), and the RNA polymerase second largest subunit region (RPB2) with primer pairs 5f2/7cr and 7cf/11ar (O'Donnell et al., 2022). PCR products of isolate SC5 were sequenced, and sequences compared to all sequences in the FUSARIOID-ID database using polyphasic identification (Crous et al., 2021) with EF1α (GenBank Accession No. ON703236) and RPB2 (OR472390) sequences. The highest similarity (100%) was with isolates of F. cugenangense, including ex-type isolate InaCC F984 (99.94% similarity) (Maryani et al., 2019). F. cugenangense is closely related to F. callistephi and F. elaeidis, but both species lack chlamydospores, and F. elaeidis has polyphialides (Lombard et al, 2019). To satisfy Koch's postulates, healthy rooted strawberry plants produced in soilless media were transplanted into 4 plastic pots (1.2-liter) containing 5% (w/v) fungal inoculum (grown on barley grain) and mixed into the top 5-cm of peat-based soilless medium. Pots were incubated at 25°C and 50% RH in a growth chamber. Four pots without inoculum served as controls. The trial was repeated. Within 8 weeks, all inoculated plants had low vigor, with necrotic and stunted roots. Root sections of control and inoculated plants were plated, and the pathogen was re-isolated from diseased roots of all inoculated plants only and confirmed as F. cugenangense based on morphology and sequence analysis. To our knowledge, this is the first report of F. cugenangense, or any member of the F. oxysporum species complex, causing root rot of strawberry in Tennessee and could be an important component of the production-limiting black root rot disease complex of strawberry.

Harnessing Walnut-Based Zinc Oxide Nanoparticles: A Sustainable Approach to Combat the Disease Complex of Meloidogyne arenaria and Macrophomina phaseolina in Cowpea.

Zinc oxide nanoparticles (ZnO NPs) exhibit diverse applications, including antimicrobial, UV-blocking, and catalytic properties, due to their unique structure and properties. This study focused on the characterization of zinc oxide nanoparticles (ZnO NPs) synthesized from Juglans regia leaves and their application in mitigating the impact of simultaneous infection by Meloidogyne arenaria (root-knot nematode) and Macrophomina phaseolina (root-rot fungus) in cowpea plants. The characterization of ZnO NPs was carried out through various analytical techniques, including UV-visible spectrophotometry, Powder-XRD analysis, FT-IR spectroscopy, and SEM-EDX analysis. The study confirmed the successful synthesis of ZnO NPs with a hexagonal wurtzite structure and exceptional purity. Under in vitro conditions, ZnO NPs exhibited significant nematicidal and antifungal activities. The mortality of M. arenaria juveniles increased with rising ZnO NP concentrations, and a similar trend was observed in the inhibition of M. phaseolina mycelial growth. SEM studies revealed physical damage to nematodes and structural distortions in fungal hyphae due to ZnO NP treatment. In infected cowpea plants, ZnO NPs significantly improved plant growth parameters, including plant length, fresh mass, and dry mass, especially at higher concentrations. Leghemoglobin content and the number of root nodules also increased after ZnO NP treatment. Additionally, ZnO NPs reduced gall formation and egg mass production by M. arenaria nematodes and effectively inhibited the growth of M. phaseolina in the roots. Furthermore, histochemical analyses demonstrated a reduction in oxidative stress, as indicated by decreased levels of reactive oxygen species (ROS) and lipid peroxidation in ZnO NP-treated plants. These findings highlight the potential of green-synthesized ZnO NPs as an eco-friendly and effective solution to manage disease complex in cowpea caused by simultaneous nematode and fungal infections.

Investigating the impact of temperature on growth rate of the root rot fungus, Gymnopus fusipes.

Gymnopus fusipes is an understudied root rot pathogen associated with multiple tree species and is linked to episodes of oak decline across the United Kingdom and Europe. Although the reported distribution of G. fusipes is broad, many observations rely solely on visual identification of fruiting bodies, which can be unreliable, and lack confirmation by molecular and/or isolation data to verify this broad ecological range. Given the paucity of information regarding the true ecological distribution of G. fusipes, it is difficult to predict and model the potential distribution of the species under both current and future climate scenarios. In this study, to determine the growth capabilities of G. fusipes across a range of ecologically relevant temperatures, five geographically diverse isolates of G. fusipes were grown at five different temperatures ranging from 4-37°C, to determine the optimal temperature for G. fusipes growth, and to establish whether geographically diverse isolates exhibit local adaptation to temperature tolerance. Incubation temperature had a significant effect on G. fusipes growth rate, with 25°C representing the optimum (P<0.001). Isolates had differing growth rates at each of the temperatures, with an isolate from the UK having the highest overall growth rate across all five temperatures tested (P<0.001), and at the optimum, increased by a mean value of over 4915 mm2. Local adaptation to temperature tolerance was not found in the isolates tested. These data demonstrate the optimal incubation temperature for future laboratory studies on G. fusipes and provide the first data on the growth rate of this pathogen across ecologically relevant climate ranges that may inform land managers, modellers, and policy makers in predicting the current and potentially future geographical limits of this widespread root rot pathogen.

A Comprehensive Perception of Biological Control Potential of Endophytes and Quality Refinement of Lagenaria siceraria.

Agriculture and livestock management practices known as organic farming rely more on internal processes than external inputs. Natural environments depend heavily on diversity, and organic farming incorporates both the stated purpose of fostering diversity as well as the use of diversity as a management tool. A more complete understanding of agriculture in terms of agro-ecology has begun to be questioned by the traditional reductionist approach to the study of agriculture. Therefore it is necessary to be aware more about the significance of microbes in processes including soil growth, plant nourishment, and the eradication of plant disease, pest, and weeds. In this study, fluorescent Pseudomonas strain (EFP56) and Trichoderma harzianum were studied for antifungal and antibacterial activity against four common root rot fungi and four common laboratory bacteria in vitro experiments. Furthermore, soil-borne disease surveillance and nutritional quality of Lagenaria siceraria, fluorescent Pseudomonas strain (EFP56) and Trichoderma harzianum were combined with neem cake and cotton cake to check their efficacy. Through the application of organic soil amendments in combination with biocontrol agents improved the quality of vegetables and their nutritional value by raising their polyphenol, carbohydrate, and protein content as well as enhancing antioxidant scavenging status. The experiments were conducted in pots and in fields to confirm their efficacy rate. The final outcomes also revealed greater induction of defense system, disease lessening and enriched fruit quality. Consortium of neem cake and cotton cake with bio-stimulants can regulate biotic as well as abiotic stress.

Suppression of Root Rot Fungal Diseases in Common Beans (Phaseolus vulgaris L.) through the Application of Biologically Synthesized Silver Nanoparticles.

The biosynthesis of silver nanoparticles (AgNPs) using plant extracts has become a safe replacement for conventional chemical synthesis methods to fight plant pathogens. In this study, the antifungal activity of biosynthesized AgNPs was evaluated both in vitro and under greenhouse conditions against root rot fungi of common beans (Phaseolus vulgaris L.), including Macrophomina phaseolina, Pythium graminicola, Rhizoctonia solani, and Sclerotium rolfsii. Among the eleven biosynthesized AgNPs, those synthesized using Alhagi graecorum plant extract displayed the highest efficacy in suppressing those fungi. The findings showed that using AgNPs made with A. graecorum at a concentration of 100 μg/mL greatly slowed down the growth of mycelium for R. solani, P. graminicola, S. rolfsii, and M. phaseolina by 92.60%, 94.44%, 75.93%, and 79.63%, respectively. Additionally, the minimum inhibitory concentration (75 μg/mL) of AgNPs synthesized by A. graecorum was very effective against all of these fungi, lowering the pre-emergence damping-off, post-emergence damping-off, and disease percent and severity in vitro and greenhouse conditions. Additionally, the treatment with AgNPs led to increased root length, shoot length, fresh weight, dry weight, and vigor index of bean seedlings compared to the control group. The synthesis of nanoparticles using A. graecorum was confirmed using various physicochemical techniques, including UV spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) analysis. Collectively, the findings of this study highlight the potential of AgNPs as an effective and environmentally sustainable approach for controlling root rot fungi in beans.

Determination of fungal root and stem rot agents of melons grown in Kumluca/Antalya

Kumluca has an important place in terms of greenhouse vegetable cultivation. Melon is among one of the main vegetables grown in the district on about 3200 decare of land. Various diseases cause decrease in the yield and quality of melons grown undercover in Türkiye. Among them, Fusarium wilt and gummy stem blight diseases especially have caused significant losses in recent years. In this research, the incidence and severity of the root and stem rot disease in Kumluca were determined by surveys made in 72 melon greenhouses in this area. Plant and soil samples were taken to the laboratory and isolations were made. As a result, Fusarium oxysporum and Didymella bryoniae were the most frequently isolated pathogens from the plant samples, followed by other Fusarium species. Fungi with the highest isolation frequency from the soil samples were Fusarium spp., Rhizoctonia solani and Macrophomina phaseolina. In the pathogenicity test, F. oxysporum, F. solani, F. verticillioides, M. phaseolina and R. solani isolates caused severe symptoms on melon seedlings. Virulence of the F. oxysporum isolates on different cucurbit species was also investigated and it was determined that they caused severe wilting on melon and watermelon seedlings, while symptoms on squash and cucumber were moderate or slight. Additionally, reactions of five melon cultivars (Yusufbey, Çıtırex, Niovi, Ferdevs and Memory) commonly grown in the region against D. bryoniae were investigated using randomly selected four pathogen isolates. All the cultivars were susceptible to the disease.

Root rot induces a core assemblage of bacterial microbiome to prevent disease infection in Sanqi ginseng

Plants rely on rhizosphere microbes as the first line of defense against pathogen invasion and for maintaining the health of itself. Increasing evidence suggests that plants recruit beneficial microbes to the roots, strengthening their resistance to pathogens. However, the response of the rhizosphere core bacterial microbiome to root rot infection remains largely unclear. In this study, we investigated the rhizosphere and bulk soil core bacterial microbiome of healthy and root rot-diseased Sanqi ginseng in genuine production areas in China. We utilized 16S amplicon sequencing, co-occurrence network analysis, and strain culture approaches to explore whether root rot-induced plant rhizosphere alterations in the bacterial core microbiome could improve disease suppression. Root rot infection had a significant impact on the rhizosphere core bacterial microbiome of Sanqi ginseng. Root rot led to a reduction in the diversity and evenness of the core bacterial microbiome in the rhizosphere, while the variability of the core bacterial community in the rhizosphere increased. In response to fungal root rot pathogen infestation, Sanqi ginseng recruited potentially beneficial bacteria with disease-suppressive functions to the rhizosphere, such as Sphingobium, Pseudoxanthomonas, Pseudomonas, Stenotrophomonas, and Flavobacterium. Function prediction analysis demonstrated a remarkable enrichment of several functional genes involved in antibiotic biosynthesis in the rhizosphere that was infected with root rot. Strain isolation and pot addition experiments further confirmed the effectiveness of root rot rhizosphere-specific enrichment of Operational Taxonomic Units (OTUs) for controlling root rot. Furthermore, co-occurrence network analysis indicated that root rot activated the disease-suppressive functions of the rhizosphere core bacterial microbiome by enhancing complexity and connectivity at the expense of network stability. These findings expand our knowledge of plant-microbe interactions and provides new evidence supporting the “cry for help” strategy for rhizosphere responses to root rot.

Utilizing bio-synthesis of nanomaterials as biological agents for controlling soil-borne diseases in pepper plants: root-knot nematodes and root rot fungus

The utilization of Trichoderma longibrachiatum filtrate as a safe biocontrol method for producing zinc nanoparticles is a promising approach for managing pests and diseases in agricultural crops. The identification of Trichoderma sp. was achieved through PCR amplification and sequencing of 18s as ON203115, while the synthesis of ZnO-NPs was accomplished by employing Trichoderma filtration. The presence of ZnO-NPs was confirmed by observing a color change to dark green, along with the use of visible and UV spectrophotometers, and the formation and chemical structure of ZnO-NPs were examined. Direct exposure to ZnO-NPs exhibited a significant inhibitory effect on the growth of Fusarium oxysporum at 80.73% compared with control. Also, the percent mortality of Meloidogyne incognita second juveniles stage (J2s) results showed 11.82%, 37.63%, 40.86%, and 89.65% after 6, 12, 24, and 72 h, respectively in vitro. Disease resistance was assessed in the greenhouse against M. incognita and F. oxysporum using the drench application of ZnO-NPs. The application of ZnO-NPs significantly reduced the disease severity of F. oxysporum and improved the quality and quantity of sweet pepper yield. In addition, the application of ZnO-NPs to M. incognita resulted in a significant reduction in the number of nematode galls, egg masses per root, eggs/egg mass, and females by 98%, 99%, 99.9%, and 95.5% respectively.Furthermore, it was observed that the application of ZnO-NPs to pepper plants not only inhibited the growth of F. oxysporum and M. incognita, but also promoted the recovery of pepper plants as indicated by improvements in stem length by 106%, root length 102%, fresh weight 112%, root fresh weight 107%, and leaf area 118% compared to healthy control plants. Additionally, real-time PCR application and DD-PCR technique revealed that the application of ZnO-NPs stimulated the secretion of certain enzymes. These findings suggest that the biosynthesized ZnO-NPs possess anti-nematode and antifungal properties, making them effective for protecting plants against M. incognita and F. oxysporum invasion in soil. This study significantly contributes to our understanding of the nematicidal and fungicidal activities of ZnO-NPs in suppressing soil-borne diseases.

Detection and Analysis of Chili Pepper Root Rot by Hyperspectral Imaging Technology

The objective is to develop a portable device capable of promptly identifying root rot in the field. This study employs hyperspectral imaging technology to detect root rot by analyzing spectral variations in chili pepper leaves during times of health, incubation, and disease under the stress of root rot. Two types of chili pepper seeds (Manshanhong and Shanjiao No. 4) were cultured until they had grown two to three pairs of true leaves. Subsequently, robust young plants were infected with Fusarium root rot fungi by the root-irrigation technique. The effective wavelength for discriminating between distinct stages was determined using the successive projections algorithm (SPA) after capturing hyperspectral images. The optimal index related to root rot between each normalized difference spectral index (NDSI) was obtained using the Pearson correlation coefficient. The early detection of root rot illness can be modeled using spectral information at effective wavelengths and in NDSI, together with the application of partial least squares discriminant analysis (PLS-DA), least squares support vector machine (LSSVM), and back-propagation (BP) neural network technology. The SPA-BP model demonstrates outstanding predictive capabilities compared with other models, with a classification accuracy of 92.3% for the prediction set. However, employing SPA to acquire an excessive number of efficient wave-lengths is not advantageous for immediate detection in practical field scenarios. In contrast, the NDSI (R445, R433)-BP model uses only two wavelengths of spectral information, but the prediction accuracy can reach 89.7%, which is more suitable for rapid detection of root rot. This thesis can provide theoretical support for the early detection of chili root rot and technical support for the design of a portable root rot detector.

FpOGT is required for fungal growth, stress response, and virulence of Fusarium proliferatum by affecting the expression of glucokinase and other glucose metabolism-related genes

O-GlcNAcylation, an important post-translational modification catalyzed by O-GlcNAc transferase (OGT), plays critical roles in several biological processes. In this study, we present our findings on the function of FpOGT in regulating physiological processes and pathogenicity of Fusarium proliferatum (Fp), the alfalfa root rot fungus. The deletion of FpOGT impaired mycelial growth and altered macroconidia morphology in Fp. Furthermore, ΔFpOGT mutant displayed altered tolerance to various stressors, including cell wall perturbing agents, osmotic stressors, metal ionic stressors, and fungicides. Deletion of FpOGT significantly decreased Fp virulence toward alfalfa. The transcriptome analysis demonstrated that FpOGT plays a regulatory role in glucose metabolic pathways, including glycolysis, tricarboxylic acid (TCA) cycle, and hexosamine biosynthesis pathway (HBP), by influencing the expression of relevant genes. The downregulation of the glucokinase gene, FpGCK, was observed in ΔFpOGT, and the disruption of FpGCK led to a decrease in Fp virulence. Additionally, FpOGT affected the expression levels of the FpGCK-AS1 isoform, thereby impacting glucokinase function. The molecular docking analysis elucidated the plausible physical interaction between FpOGT and FpGCK, thereby offering valuable insights into their interrelationship. These findings underscore the indispensable involvement of FpOGT, the sole O-GlcNAc transferase in Fp, in various biological processes and the pathogenicity through its regulation of fundamental metabolic processes. Consequently, this study emphasizes the significance and elucidates the molecular mechanism underlying the role of O-GlcNAc transferase in diverse fundamental biological processes and the pathogenicity of phytopathogenic fungi.

Evaluation of Enhancing Biochar and the fungus Glomus mosseae in the Growth of Common Bean, Phaseolus vulgaris infected with Rhizoctonia solani

Abed, R.M. 2024. Evaluation of Enhancing Biochar and the fungus Glomus mosseae in the Growth of Common Bean, Phaseolus vulgaris infected with Rhizoctonia solani. Arab Journal of Plant Protection, 42(2): 215-223. https://doi.org/10.22268/AJPP-001232 The possible role of biochar and its interaction with the fungus Glomus mosseae in promoting the growth of the common bean plant, Phaseolus vulgaris L., grown under biological stress of infection with the pathogenic fungus, Rhizoctonia solani was investigated. The results showed that the addition of biochar and the treatment with mycorrhizal fungus, and the interaction between them, led to a significant reduction in the seedling mortality and the severity of root rot disease of the common bean plant. The results obtained showed that the mycorrhizal traits, which included infection rate, severity of infection, and number of spores, were affected by the presence of the pathogenic fungus, as all the studied mycorrhizal traits decreased, compared to the treatment of the mycorrhizal fungus in the absence of the root rot fungus. The results obtained also showed that the decrease in the disease had a positive effect on the vegetative and root plant growth and nutrients content. The results obtained encourages the application of biochar as an alternative to chemical pesticides for the control of common bean root rot. Keywords: BioChar, common bean, Rhizoctonia solani, Glomus mosseae, mycorrhiza

Heterobasidion annosum and Armillaria ostoyae significantly reduce radial growth during three years before stem death in infected Pinus pinaster

Butt and root-rot diseases caused by Armillaria sp. and Heterobasidion sp. are highly destructive to conifers worldwide. These diseases lead to loss of growth, wood degradation, and tree mortality, often necessitating premature logging. However, little is known about the effect of infection on the growth and mortality of adult pines during forest development. In this study, mature maritime pines were sampled from two forest sites in south-west France. In 2013, the Sanguinet site provided both healthy (asymptomatic) and Heterobasidion annosum-infected pines, while in 2019 the Mano site also provided Armillaria ostoyae-infected pines. Radial growth dynamics were compared between healthy and infected pines using two complementary approaches taking into account the diameter of each tree: 1. Compensation over 10 years and year by year comparisons of mean (dendrochronogram) between groups of pines with same Last Year of Radial Growth (LYRG); 2. Analysis of covariance by modeling the relationship between basal area increment and basal area in healthy or infected pines for each LYRG. Our results indicate that symptomatic trees infected by Heterobasidion annosum are characterised by a rapid reduction in radial growth across the entire tree circumference. The covariance method was more efficient to show that the radial growth of infected trees was significantly lower (between 25% and 72% loss) in the three years preceding the year of growth arrest, on both sites, i.e., for two different periods of years. For Armillaria ostoyae, growth data shows the same trends than for H. annosum, with a sharp decline over the last 2–3 years of growth. Covariance results for LYRG 2018 and 2019 reveal that infection symptoms significantly reduces the radial growth of infected trees compared to asymptomatic trees over the last three years of growth. These results show that infection of maritime pine by butt and root-rot fungi can lead to a rapid decrease in radial growth, and this decrease is independent of the calendar year of cambial death at breast height.

Full-length genome characterization of a novel mitovirus isolated from the root rot fungus Armillaria mellea.

Members of the genus Armillaria belong to the group of pathogenic and facultative saprotrophic fungi that are generally known as one of the causative agents of white root rot in infected plants including deciduous and evergreen trees and shrubs. Although several single-stranded RNA mycoviruses were previously described in different Armillaria species, there is no report on mitoviruses (one of the simplest RNA viruses of fungal hosts) known to infect Armillaria taxa. In this study, a new mitovirus denominated "Armillaria mellea mitovirus 1" (AmMV1) was identified in the sporophore samples of Armillaria mellea, commonly known as honey mushroom. AmMV1 has a genome length of 4440 nucleotides and a G + C content of 48%. It encompasses a single open reading frame (ORF) that encodes an RNA-dependent RNA polymerase (RdRp). Comparison through BLASTp analysis revealed that the RdRp domain of AmMV1 shares a sequence identity ranging from 33.43% to 43.27% with RdRp domains of Duamitovirus genus members, having the highest similarity (43.27%) to Rhizoctonia solani mitovirus 94. According to phylogenetic analysis, AmMV1 is classified as a member of the genus Duamitovirus belonging to the Mitoviridae family. This marks the initial instance of a mitovirus identified in Armillaria spp..

Assessment the Efficiency of the Bioagent Bacillus velesensis and the Biohealth Formula with Fungicide Beltanol in Control of Fusarium solani Causing Pepper Root Rot

The aim of this study was isolating and diagnosing the causative agent of root rot of pepper in Karbala province and control it using some biological applications. The results showed that the main pathogenic fungus of root rot and damping-off pepper in Karbala Province was Fusarium solani. This fungus was highly pathogenic by inhibition germination of all pepper seeds on the culture medium and in plastic pots. The treatment of integration between among Bacillus velesensis + Biohealth + Beltanol displayed the highest effectiveness in control of the pathogenic F.solani, as it reduced the disease incidence and severity to 9.00, 6.66%, respectively, compared to the pathogenic fungus alone, which amounted to 100%, 86.6%, respectively.

Synergistic mechanism of Bacillus subtilis Czk1 combined with propiconazole and tebuconazole mixtures against Pyrrhoderma noxium

BackgroundBrown root rot disease is one of the devastating diseases in the rubber production process. It is not easy to be detected in the early stage of the disease. Our early research revealed that the rubber tree brown root rot fungus Pyrrhoderma noxium Pn006 was effectively inhibited by Bacillus subtilis Czk1 and 25% propiconazole–tebuconazole, and that the two agents might work in synergy. Therefore, in this investigation, we used non-targeted metabolomic method to evaluate the synergistic mechanism of B. subtilis Czk1 and 25% propiconazole–tebuconazole on Pyrrhoderma noxium Pn006.ResultsMetabolomics analysis identified 708 unique metabolic markers, including mainly lipids and lipid-like molecules, organic acids, alcohols, ketones, alkaloids and their derivatives, nucleotides and their analogues, benzene ring compounds and amino acids and their derivatives. Further screening identified 105 key metabolic markers that could be potential biomarkers to reveal the mechanism of biocontrol bacteria and chemical fungicides combination synergy. Three key metabolic pathways were found in pathway enrichment, including linolenic acid metabolism, benzoic acid degradation, and valine, leucine and isoleucine degradation.ConclusionsThe mechanism might be related to the influence of the energy supply and cell functional integrity of pathogenic fungal cells.Critical relevance statement A metabolomic method was utilized to investigate the synergistic effects of B. subtilis Czk1 and 25% propiconazole–tebuconazole use on Pyrrhoderma noxium Pn006.Graphical

Molten Shellac Resin Mix with Soil Could Be Useful in Crop Protection Modelled With Chick Pea

Rural Society produce has great economic viability that needs to be explored to help improve their income. Plant and insect resins that form a major produce from rural background in India could be explored for further use that can increase their value. In this article we demonstrate the insect resin lac could be used in crop protection since addition of it to soil followed by water retention and plant injury protected Chick pea seedlings as compared to control. In this article we show it for the first time that molten hot shellac (1:25parts) mixed with organic manure used for seed germination conferred protection to seedlings against water logging and water deficit related decay, recovery from physical injury. The basis of protection could be lac altering the dielectric nature of soil, it altering the soil texture or directly inhibiting fungal mycelium responsible for root rot. In water logged condition or drought, root rot fungi could play a major role in destruction of crop. To observe the protection conferred by lac resin, non-pathogenic agaricus fungi was modelled for observing mycelial spread over tin metal plate.

Biocontrol agent of root-knot nematode Meloidogynejavanica and root-rot fungi, Fusariumsolani in okra morphological, anatomical characteristics and productivity under greenhouse conditions

This study was conducted to evaluate the ability of some fungal culture filtrate, as biocontrol agents against okra wilt caused by Fusariumsolani. and Meloidogynejavanica. In the present study, fungal culture filtrates (FCFs) of Aspergillusterreus (1), Aspergillusterreus (2), Penicilliumchrysogenum, and Trichoderma spp. were tested against M.javanica in vitro. The effects of P.chrysogenum and Trichoderma spp. (FCFs) in controlling root-rot fungi and root-knot nematode disease complex on okra plants were studied under greenhouse conditions (In vivo). In vitro experiment, the results revealed cumulative rate of J2s mortality of M.javanica reached to 97.67 and 95% by P.chrysogenum and Trichoderma spp., respectively, after 72 h. incubation. Additionally, Trichoderma spp exhibited the most effective inhibitory activity against the pathogen's radial growth, with a percentage of 68%. P.chrysogenum ranked second with 53.88%, while A.terreus (2) demonstrated the weakest inhibitory effect of 24.11%. T6 [Nematode infection (M.javanica) + Fungus infection (F.solani) + Overflowed with fungal culture filtrate (P.chrysogenum)] and T8 [Nematode infection (M.javanica) + Fungus infection (F.solani) + spray with fungal culture filtrate (P.chrysogenum)] had the greatest effects on nematode galling indices on okra roots and substantially reduced the reproductive factors in the greenhouse (In vivo experiment). T6 was the best treatment to decrease disease severity, as reached (28%) relatively. On the other hand, T12 [(Fungus infection (F.solani) + (Dovex 50% fungicide with irrigation water)] recorded the lowest disease severity reaching (8%) relatively. The results showed that nematode infection or fungus infection or both decreased all studied anatomical characteristics of okra root, stem, and leaves. We concluded from this study that root-knot nematode and root-rot fungi were reduced by using fungal culture filtrates and could improve plant growth.

Characterization and Control of Root Rot and Wilt Fungi of Geranium (Pelargonium graveolens L.) with Special Reference to First Record for Fusarium proliferatum as Wilt Pathogen on Geranium in Egypt

Characterization and Control of Root Rot and Wilt Fungi of Geranium (Pelargonium graveolens L.) with Special Reference to First Record for Fusarium proliferatum as Wilt Pathogen on Geranium in Egypt

Plant disease management with amelioration of systemic resistance in soybean by endophytic fungi associated with GC-MS metabolic profiling of Chaetomium sp.,

Plants exhibit beneficial associations between fungal endophytes and roots for better growth, disease suppression, and stress tolerance. Considerable information is now available about the beneficial role of fungal endophytes. In this study, endophytic fungi Chaetomium sp., Curvularia chonburiensis, C. specifera, C. hawaiiensis, Rhizoctonia solani, Fusarium solani, Talaromyces assiutensis and T. trachyspermus isolated and evaluated for nematocidal activity against a root-knot nematode Meloidogyne javanica. The culture filtrates of endophytic fungi were prepared and used to check their efficacy against root knot nematodes. The culture filtrates of endophytic fungi were applied to pot and field experiments using soybean as host plants. In vitro study of these endophytic fungal culture filtrates showed strong nematocidal activity by killing juveniles of M. javanica to a certain degree, while Chaetomium sp., and Talaromyces assiutensis showed 100% mortality rate after 48 h. The application of Cephalosporium sp., Chaetomium sp., Talaromyces trachyspermus and T. assiutensis suppressed root rotting fungi of soybean in both screen house and field plots experiments. Significance of fungal isolates was further confirmed by repeated experiments. Endophytic fungi also showed positive impacts on the host plants by increasing the rate of their growth and improving their tolerance level to biotic stress which was evident by the production of increased amounts of resistance markers like salicylic acid and polyphenol contents with subsequent improvement of the antioxidant status. The n-hexane fraction of the culture filtrate of Chaetomium sp., were subjected to GC-MS analysis for the identification of compounds and some new compounds have been reported for the first time from this fungus. The results will facilitate a better understanding of host plant and fungal interaction and are likely to assist in the screening and utilization of beneficial microbes.