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Diseases caused by the fungus Sclerotinia sclerotiorum are managed mainly through fungicide applications in canola and dry bean. Accurate estimation of the risk of disease development on these crops could help farmers make spraying decisions. Five machine learning (ML) models were evaluated in classification and regression modes for predicting disease establishment under different air temperatures and leaf wetness duration conditions. Model algorithms were trained and tested using 20-fold cross validation. Correspondence between predicted and observed values were measured using Cohen’s Kappa (classification) and Lin’s concordance coefficients (regression). The artificial neural network (ANN) algorithms had average accuracies ≥ 89% (classification) and R2 ≥ 88% (regression) on canola and dry bean and their correspondence agreements were ≥ 0.83, which is considered substantial to almost perfect. In contrast, logistic regression algorithms had accuracies of 88% for dry bean and 78% for canola; other models were similarly inconsistent. Implementation of ANN models in disease warning systems could help farmers with spraying decisions. At the same time, these models provide insights on temperature and leaf wetness requirements for development of S. sclerotiorum diseases in these crops. Results of this study show the potential of ML models as tools for epidemiological studies on other pathosystems.

Pestalotiopsis and related genera, including Neopestalotiopsis and Pseudopestalotiopsis have damaged many plants for many decades; however, there is little available information about the fungi on tropical fruit in Thailand. This study isolated and characterized pestalotioid fungi on tropical fruit, investigated host specificity, and screened whether plant extracts could control the fungi. In total, 53 diseased fruit samples were sampled from eight types of fruit trees (jackfruit, rose apple, mangosteen, plum, snake fruit, rambutan, strawberry, and avocado). Based on morphological characteristics, 44 isolates were classified as belonging to pestalotioid taxa. Of these isolates, seven with distinct characteristics were selected for identification using molecular analysis, and six isolates were identified as Neopestalotiopsis and one as Pseudopestalotiopsis. In the cross-inoculation experiment, the isolates exhibited nonhost specificity and could infect at least two host plants. The isolates were used to screen for a potential biocontrol resource using six crude plant extracts (clove, ginger, lemongrass, mangosteen, roselle, and turmeric). All crude extracts except mangosteen could inhibit the growth of Neopestalotiopsis and Pseudopestalotiopsis. Application of crude plant extracts could be a potential treatment to control these diseases on tropical fruit.

Blast disease incited by Magnaporthe oryzae is a major threat to sustain rice production in all rice growing nations. The pathogen is widely distributed in all rice paddies and displays rapid aerial transmissions, and seed-borne latent infection. In order to understand the genetic variability, host specificity, and molecular basis of the pathogenicity-associated traits, the whole genome of rice infecting Magnaporthe oryzae (Strain RMg_Dl) was sequenced using the Illumina and PacBio (RSII compatible) platforms. The high-throughput hybrid assembly of short and long reads resulted in a total of 375 scaffolds with a genome size of 42.43 Mb. Furthermore, comparative genome analysis revealed 99% average nucleotide identity (ANI) with other oryzae genomes and 83% against M. grisea, and 73% against M. poe genomes. The gene calling identified 10,553 genes with 10,539 protein-coding sequences. Among the detected transposable elements, the LTR/Gypsy and Type LINE showed high occurrence. The InterProScan of predicted protein sequences revealed that 97% protein family (PFAM), 98% superfamily, and 95% CDD were shared among RMg_Dl and reference 70-15 genome, respectively. Additionally, 550 CAZymes with high GH family content/distribution and cell wall degrading enzymes (CWDE) such endoglucanase, beta-glucosidase, and pectate lyase were also deciphered in RMg_Dl. The prevalence of virulence factors determination revealed that 51 different VFs were found in the genome. The biochemical pathway such as starch and sucrose metabolism, mTOR signaling, cAMP signaling, MAPK signaling pathways related genes were identified in the genome. The 49,065 SNPs, 3267 insertions and 3611 deletions were detected, and majority of these varinats were located on downstream and upstream region. Taken together, the generated information will be useful to develop a specific marker for diagnosis, pathogen surveillance and tracking, molecular taxonomy, and species delineation which ultimately leads to device improved management strategies for blast disease.

To identify apple canker casual agents and evaluate their pathogenicity and virulence in apple production hubs including West Azarbaijan, Isfahan and Tehran provinces; samples were collected from symptomatic apple trees. Pathogenic isolates on the detached branches were identified as Cytospora cincta, Diplodia bulgarica, Neoscytalidium dimidiatum and Eutypa cf. lata. E. cf. lata was reported as a potential apple canker causal agent in Iran for the first time based on the pathogenicity test on the detached branches, whereas it caused no canker symptoms in apple trees until 6 months after inoculation. Currently, E. cf. lata seems to be adapted to a single city. C. cincta, D. bulgarica and N. dimidiatum caused canker symptoms in apple trees. “C. cincta” and also “C. cincta and N. dimidiatum” were the most widespread and aggressive apple canker species, respectively, associated with apple canker in Iran. Therefore, they are considered to be the main threat to apple production in Iran and should be carefully monitored. Disease progress curve, area under the disease progress curve and optimum temperatures were determined for mentioned species. It is concluded that the establishment of each species occurs in appropriate areas and times in terms of the optimum temperature for their growth.

Luobuma (Apocynum venetum, Poacynum pictum, and P. hendersonni) are perennial herbs widely used in the textile and medical industries and ecological restoration. In the summer of 2020, reddish-brown or off-white sunken shape necrotic lesions were observed on the stems and shoots of seven Luobuma ecotypes grown in the field in Yuzhong County, Gansu province of China, which is a limiting factor that affects the growth, function and application of Luobuma. To make clear whether the new symptoms were caused by a novel pathogen, a combined research in field and greenhouse was conducted. Based on the morphological and molecular analysis results, the pathogen causing the necrotic lesions was identified as Boeremia exigua var. rhapontica. The incidence and disease index of the seven ecotypes in the field ranged from 11.49 to 33.68% and 6.63 to 23.01, respectively, from 2020 to 2021. The results showed that the disease severity gradually increased with the growing season. According to the pathogenicity analysis of the eight ecotypes in the greenhouse, the ecotypes Pp-BMK and Pp-BMH were susceptible, while ecotype Pp-BMQ was resistant to Boeremia exigua var. rhapontica infection. Thus, the present study provides a theoretical basis for preventing and controlling the stem and leaf necrotic lesions disease on Luobuma by planting resistant varieties/ecotypes. To our knowledge, this is the first report of stem necrotic lesions and leaf spots on Luobuma caused by B. exigua var. rhapontica.

The bioremediation of heavy metals contaminated soils with macrofungi is a new and promising approach; hence Agaricus bisporus (Large) sing has potentially shown accumulating ability to Cd contamination. This study focused on the tolerance response by A. bisporus to different contents of Cd in the closed cup and the flat stage of fruiting body development. The contents of Cd, soluble protein, sugar, low molecular weight organic acids (LMWOAs), and antioxidant activity were investigated. The bioaccumulation factor and transfer factor results revealed that Cd accumulated in the cap of A. bisporus more than that in the stipe with the highest content being 18.38 mg kg−1 dry weight at the closed cup stage under 414.28 mg kg−1 Cd stress. High Cd content stress increased soluble protein, proline, and malonaldehyde contents at both stages; while higher peroxidase, catalase, ascorbic acid peroxidase activities, and LMWOAs contents were only recorded at the closed cup stage. On the other hand, Superoxide dismutase activities and soluble sugar content showed a complex trend. Overall, these results have successfully established that A. bisporus could resort to modulating its metabolism to avoid the destructive effects of Cd stress and could successfully accumulate Cd in the soil, which is a promising prospect for the remediation of Cd-contaminated soils.

The production and leaf quality of Telfairia occidentalis in Cameroon are gravely threatened by leaf spot disease. A field study was conducted in July 2019 and 2020 to determine the influence of tillage systems and sowing dates on the incidence of Telfairia occidentalis leaf spot caused by Phoma sorghina. A randomized block design with three replications and four planting dates was used. The soil physicochemical properties were also determined. Data for disease incidence were registered once every two weeks and submitted to generalized linear model for statistical analysis. The means were separated by Duncan’s multiple range test at a 95% confidence interval. Calculations for disease incidence and statistical analysis were conducted using the Microsoft Excel program and SPSS version 23, respectively. Statistical analysis revealed that the zero tilled field generally registered a lower leaf spot disease incidence than the tilled field, which was highly significant (p ≤ 0.05). In addition, the second sowing date in the zero tilled field proved to be better in terms of low disease incidence than other sowing dates employed in the study. Therefore, to minimize the devastating effects of leaf spot disease, zero tillage coupled with the second sowing date could be exploited.

Antimicrobial resistance has become one of the major threats to human health. Therefore, there is a strong need for novel antimicrobials with new mechanisms of action. The kingdom of fungi is an excellent source of antimicrobials for this purpose because it encompasses countless fungal species that harbor unusual metabolic pathways. Previously, we have established a library of secondary metabolites from 10,207 strains of fungi. Here, we screened for antimicrobial activity of the library against seven pathogenic bacterial strains and investigated the identity of the active compounds using ethyl acetate extraction, activity-directed purification using HPLC fractionation and chemical analyses. We initially found 280 antimicrobial strains and subsequently identified 17 structurally distinct compounds from 26 strains upon further analysis. All but one of these compounds, berkchaetoazaphilone B (BAB), were known to have antimicrobial activity. Here, we studied the antimicrobial properties of BAB, and found that BAB affected energy metabolism in both prokaryotic and eukaryotic cells. We conclude that fungi are a rich source of chemically diverse secondary metabolites with antimicrobial activity.

Cinnamaldehyde (Cin) is a natural product obtained from cinnamon and is reported to have a potential anti-fungal, anti-oxidant, anti-inflammatory and anticancer effect. The present study investigated the possible protective role of Cin against tenuazonic acid-induced mycotoxicity in the murine model. Tenuazonic acid (TeA), a toxin produced by Alternaria is a common contaminant in tomato and tomato-based products. Here, Swiss male mice were administered with TeA isolated from Paradendryphiella arenariae (MW504999) (source-tomato) through injection (238 µg/kg BW) and ingestion (475 µg/kg BW) routes for 2 weeks. Thereafter, the prophylaxis groups were treated with Cin (210 mg/kg BW). The experiment was carried out for 8 weeks. The treated groups were compared to the oral and intra-peritoneal experimental groups that received the toxin solely for 8 weeks. Haematological, histopathological and biochemical aspects of the experimental and the control mice were analysed. Sub-chronic intoxication of mice with TeA showed elevated malondialdehyde (MDA), reduced catalase (CAT) and superoxide dismutase (SOD) production; abnormal levels of aspartate transaminase (AST) and alanine transaminase (ALT). Treatment with Cin reversed TeA-induced alterations of antioxidant defense enzyme activities and significantly prevented TeA-induced organ damage. Thus, cinnamaldehyde showed therapeutic effects and toxicity reduction in TeA induced mycotoxicosis.

Cell death processes in eukaryotes shape normal development and responses to the environment. For plant-microbe interactions, initiation of host cell death plays an important role in determining disease outcomes. Cell death pathways are frequently initiated following detection of pathogen-derived molecules which can lead to resistance or susceptibility to disease depending on pathogen lifestyle. We previously identified several small secreted proteins (SSPs) from the wheat-infecting fungus Zymoseptoria tritici that induce rapid cell death in Nicotiana benthamiana following Agrobacterium-mediated delivery and expression (agroinfiltration). Here we investigated whether the execution of host cells was mechanistically similar in response to different Z. tritici SSPs. Using RNA sequencing, we found that transient expression of four Z. tritici SSPs led to massive transcriptional reprogramming within 48 hours of agroinfiltration. We observed that distinct host gene expression profiles were induced dependent on whether cell death occurs in a cell surface immune receptor-dependent or -independent manner. These gene expression profiles involved differential transcriptional networks mediated by WRKY, NAC and MYB transcription factors. In addition, differential expression of genes belonging to different classes of receptor-like proteins and receptor-like kinases was observed. These data suggest that different Z. tritici SSPs trigger differential transcriptional reprogramming in plant cells.

International audience; The black truffle Tuber melanosporum was disseminated all over the world, propelled by the development of a wide variety of empirical practices. A widespread practice, called ‘truffle trap’, consists of placing pieces of truffles into excavations dug under host trees, and of collecting truffle in these traps in the next years. This research aims at (1) evaluating the effect of this practice on fruitbody production based on the analysis of 9924 truffle traps installed in 11 orchards across T. melanosporum native area in France and (2) exploring the mechanisms involved in fruitbody emergence using traps where the genotypes of introduced truffles were compared with those of fruitbodies collected in the same traps. We confirmed that truffle traps provide a major and highly variable part of truffle ground production, representing up to 89% of the collected fruitbodies. We evidenced a genetic link between introduced spores and collected fruitbodies, and then demonstrated that truffle growers provide paternal partners for mating with local maternal mycelia. We also highlighted that soil disturbance stimulate the vegetative development of established maternal mycelia. This research supports that a widely used traditional practice enhances fruitbody production by shaping favorable conditions and providing sexual partners required for fruiting.The black truffle Tuber melanosporum was disseminated all over the world, propelled by the development of a wide variety of empirical practices. A widespread practice, called ‘truffle trap’, consists of placing pieces of truffles into excavations dug under host trees, and of collecting truffle in these traps in the next years. This research aims at (1) evaluating the effect of this practice on fruitbody production based on the analysis of 9924 truffle traps installed in 11 orchards across T. melanosporum native area in France and (2) exploring the mechanisms involved in fruitbody emergence using traps where the genotypes of introduced truffles were compared with those of fruitbodies collected in the same traps. We confirmed that truffle traps provide a major and highly variable part of truffle ground production, representing up to 89% of the collected fruitbodies. We evidenced a genetic link between introduced spores and collected fruitbodies, and then demonstrated that truffle growers provide paternal partners for mating with local maternal mycelia. We also highlighted that soil disturbance stimulate the vegetative development of established maternal mycelia. This research supports that a widely used traditional practice enhances fruitbody production by shaping favorable conditions and providing sexual partners required for fruiting.

Plant pathogens deliver effector proteins to reprogramme a host plants circuitry, supporting their own growth and development, whilst thwarting defence responses. A subset of these effectors are termed avirulence factors (Avr) and can be recognised by corresponding host resistance (R) proteins, creating a strong evolutionary pressure on pathogen Avr effectors that favours their modification/deletion to evade the immune response. Hence, identifying Avr effectors and tracking their allele frequencies in a population is critical for understanding the loss of host recognition. However, the current systems available to confirm Avr effector function, particularly for obligate biotrophic fungi, remain limited and challenging. Here, we explored the utility of the genetically tractable wheat blast pathogen Magnaporthe oryzae pathotype Triticum (MoT) as a suitable heterologous expression system in wheat. Using the recently confirmed wheat stem rust pathogen (Puccina graminis f. sp. tritici) avirulence effector AvrSr50 as a proof-of-concept, we found that delivery of AvrSr50 via MoT could elicit a visible Sr50-dependant cell death phenotype. However, activation of Sr50-mediated cell death correlated with a high transgene copy number and transcript abundance in MoT transformants. This illustrates that MoT can act as an effective heterologous delivery system for fungal effectors from distantly related fungal species, but only when enough transgene copies and/or transcript abundance is achieved.

Metacommunity theory provides a framework for how community patterns arise from processes across scales, which is relevant for understanding patterns in host-associated microbial assemblages. Microbial metacommunities may have important roles in host health through interactions with pathogens; however, it is unclear how pathogens affect host microbial metacommunities. Here, we studied relationships between a fungal pathogen and a host-associated microbial metacommunity. We hypothesized that a fungal pathogen of bats, Pseudogymnoascus destructans, correlates with a shift in metacommunity structure and changes in relationships between community composition, and factors shaping these assemblages, such as ecoregion. We sampled bat cutaneous microbial assemblages in the presence/absence of P. destructans and analyzed microbial metacommunity composition and relationships with structuring variables. Absence of P. destructans correlated with a metacommunity characterized by a common core microbial group that was lacking in disease positive bats. Additionally, P. destructans presence correlated with a change in the relationship between community structure and ecoregion. Our results suggest that the fungal pathogen intensifies local processes influencing a microbial metacommunity and highlights the importance of cutaneous microbial assemblages in host–pathogen interactions.

White-nose syndrome (WNS) is an emergent wildlife fungal disease of cave-dwelling, hibernating bats that has led to unprecedented mortalities throughout North America. A primary factor in WNS-associated bat mortality includes increased arousals from torpor and premature fat depletion during winter months. Details of species and sex-specific changes in lipid metabolism during WNS are poorly understood and may play an important role in the pathophysiology of the disease. Given the likely role of fat metabolism in WNS and the fact that the liver plays a crucial role in fatty acid distribution and lipid storage, we assessed hepatic lipid signatures of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus) at an early stage of infection with the etiological agent, Pseudogymnoascus destructans (Pd). Differences in lipid profiles were detected at the species and sex level in the sham-inoculated treatment, most strikingly in higher hepatic triacylglyceride (TG) levels in E. fuscus females compared to males. Interestingly, several dominant TGs (storage lipids) decreased dramatically after Pd infection in both female M. lucifugus and E. fuscus. Increases in hepatic glycerophospholipid (structural lipid) levels were only observed in M. lucifugus, including two phosphatidylcholines (PC [32:1], PC [42:6]) and one phosphatidylglycerol (PG [34:1]). These results suggest that even at early stages of WNS, changes in hepatic lipid mobilization may occur and be species and sex specific. As pre-hibernation lipid reserves may aid in bat persistence and survival during WNS, these early perturbations to lipid metabolism could have important implications for management responses that aid in pre-hibernation fat storage.

Sunflower Verticillium Wilt and Leaf Mottle (SVW), caused by Verticillium dahliae (Kleb.; Vd), is a soil-borne disease affecting sunflower worldwide. A single dominant locus, known as V1, was formerly effective in controlling North-American Vd races, whereas races from Argentina, Europe and an emerging race from USA overcome its resistance. This emphasizes the need for identifying broad-spectrum genetic resistance (BSR) sources. Here we characterize two sunflower mapping populations (MPs) for SVW resistance: a biparental MP and the association MP from the National Institute of Agricultural Technology (INTA), under field growing conditions. Nine field-trials (FTs) were conducted in highly infested fields in the most SVW-affected region of Argentina. Several disease descriptors (DDs), including incidence and severity, were scored across four phenological stages. Generalized linear models were fitted according to the nature of each variable, adjusting mean phenotypes for inbred lines across and within FTs. Comparison of these responses allowed the identification of novel BSR sources. Furthermore, we present the first report of SVW resistance heritability, with estimates ranging from 35 to 45% for DDs related to disease incidence and severity, respectively. This study constitutes the largest SVW resistance characterization reported to date in sunflower, identifying valuable genetic resources for BSR-breeding to cope with a pathogen of increasing importance worldwide. EEA Pergamino Fil: Montecchia, Juan Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Fass, Mónica I. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Cerrudo, Ignacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Quiroz, Facundo José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Nicosia, Salvador Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Maringolo, Carla Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Di Rienzo, Julio. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina Fil: Troglia, Carolina Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Hopp, Horacio Esteban. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Escande, Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina Fil: Gonzalez, Julio Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Sección Girasol; Argentina Fil: Alvarez, Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; Argentina Fil: Heinz, Ruth Amelia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Lia, Veronica Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina Fil: Lia, Veronica Viviana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnologoía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Agrobiotecnología y Biología Molecular (IABIMO); Argentina

Collections of microfungi on bamboo and grasses in Thailand revealed an interesting species morphologically resembling Lophiostoma, but which can be distinguished from the latter based on multi-locus phylogeny. In this paper, a new genus, Sublophiostoma is introduced to accommodate the taxon, S. thailandica sp. nov. Phylogenetic analyses using combined ITS, LSU, RPB2, SSU, and TEF sequences demonstrate that six strains of the new species form a distinct clade within Pleosporales, but cannot be assigned to any existing family. Therefore, a new family Sublophiostomataceae (Pleosporales) is introduced to accommodate the new genus. The sexual morph of Sublophiostomataceae is characterized by subglobose to hemisphaerical, ostiolate ascomata, with crest-like openings, a peridium with cells of textura angularis to textura epidermoidea, cylindric-clavate asci with a bulbous or foot-like narrow pedicel and a well-developed ocular chamber, and hyaline, fusiform, 1-septate ascospores surrounded by a large mucilaginous sheath. The asexual morph (coelomycetous) of the species are observed on culture media.

Lasiodiplodia theobromae and Neofusicoccum parvum are serious worldwide-distributed plant pathogenic fungi with a wide host range in tropical and temperate climates. They cause fruit rot, canker, and dieback of twigs in various woody plants. Protection of pruning wounds using fungicides is the prevalent strategy for the management of the diseases caused by these fungi. Chemical control of plant diseases is not environmentally safe and the residues of fungicides are a threat to nature. Furthermore, genetic resources of resistance to plant diseases in woody plants are limited. The aim of this study was to investigate the efficiency of RNA silencing using an efficient hairpin structure based on Tef-1α gene for the management of L. theobromae and N. parvum. Hairpin structure of Tef-1α was cloned in pFGC5941 binary vector and the recombinant construct was named pFGC-TEF-d. Transient expression of pFGC-TEF-d using Agrobacterium LBA4404 in grapevine (Bidaneh Sefid cv.) and strawberry cultivars (Camarosa and Ventana) led to a reduction in disease progress of L. theobromae. The disease reduction in grapevine was estimated by 55% and in strawberries cultivars Camarosa and Ventana by 58% and 93%, respectively. Further analysis of transient expression of pFGC-TEF-d in strawberry (Camarosa) shown disease reduction using Neofusicoccum parvum. Here we introduce RNAi silencing using pFGC-TEF-d construct as an efficient strategy to the management of L. theobromae and N. parvum for the first time.

As the incidence of fungicide resistance in plant pathogens continues to increase, control of diseases and the management of resistance would be greatly aided by rapid diagnostic methods. Quantitative allele-specific PCR (ASqPCR) is an ideal technique for the in-field analysis of fungicide resistance as it can quantify the frequency of mutations in fungicide targets. We have applied this technique to the fungal pathogen Blumeria graminis f. sp. tritici (Bgt), the causal agent of wheat powdery mildew. In Australia, strobilurin-resistant Bgt was first discovered in 2016. Molecular analysis revealed a nucleotide transversion in the cytochrome b (cytb) gene in the cytochrome bc1 enzyme complex, resulting in a substitution of alanine for glycine at position 143 (G143A). We have developed an in-field ASqPCR assay that can quantify both the resistant (A143) and sensitive (G143) cytb alleles down to 1.67% in host and Bgt DNA mixtures, within 90 min of sample collection. The in situ analysis of samples collected during a survey in Tasmania revealed A143 frequencies ranging between 9–100%. Validation of the analysis with a newly developed laboratory based digital PCR assay found no significant differences between the two methods. We have successfully developed an in-field quantification method, for a strobilurin-resistant allele, by pairing the ASqPCR assay on a lightweight qPCR instrument with a quick DNA extraction method. The deployment of these type of methodologies in the field can contribute to the effective in-season management of fungicide resistance.

Plant growth environment plays an important role in shaping soil microbial communities. To understand the response of soil rhizosphere microbial communities in Oplopanax elatus Nakai plant to a changed growth conditions from natural habitation to cultivation after transplant. Here, a comparative study of soil chemical properties and microbial community using high-throughput sequencing was conducted under cultivated conditions (CT) and natural conditions (WT), in Changbai Mountain, Northeast of China. The results showed that rhizosphere soil in CT had higher pH and lower content of soil organic matter (SOM) and available nitrogen compared to WT. These changes influenced rhizosphere soil microbial communities, resulting in higher soil bacterial and fungi richness and diversity in CT soil, and increased the relative abundance of bacterial phyla Acidobacteria, Chloroflexi, Gemmatimonadetes, Firmicutes and Patescibacteria, and the fungi phyla Mortierellomycota and Zoopagomycota, while decreased bacterial phyla Actinobacteria, WPS-2, Gemmatimonadetes, and Verrucomicrobia, and the fungi phyla Ascomycota, and Basidiomycota. Redundancy analysis analysis indicated soil pH and SOM were the primarily environmental drivers in shaping the rhizosphere soil microbial community in O. elatus under varied growth conditions. Therefore, more attention on soil nutrition management especially organic fertilizer inputs should be paid in O. elatus cultivation.

Humicolagrisea var. thermoidea is an aerobic and thermophilic fungus that secretes the GH11 xylanase HXYN2 in the presence of sugarcane bagasse. In this study, HXYN2 was expressed in Pichiapastoris and characterized biochemically and structurally in the presence of beechwood xylan substrate and ferulic acid (FA). HXYN2 is a thermally stable protein, as indicated by circular dichroism, with greater activity in the range of 40–50 °C and pH 5.0–9.0, with optimal temperature and pH of 50 °C and 6.0, respectively. FA resulted in a 75% increase in enzyme activity and a 2.5-fold increase in catalytic velocity, catalytic efficiency, and catalytic rate constant (kcat), with no alteration in enzyme affinity for the substrate. Fluorescence quenching indicated that FA forms a complex with HXYN2 interacting with solvent-exposed tryptophan residues. The binding constants ranged from moderate (pH 7.0 and 9.0) to strong (pH 4.0) affinity. Isothermal titration calorimetry, structural models and molecular docking suggested that hydrogen bonds and hydrophobic interactions occur in the aglycone region inducing conformational changes in the active site driven by initial and final enthalpy- and entropy processes, respectively. These results indicate a potential for biotechnological application for HXYN2, such as in the bioconversion of plant residues rich in ferulic acid.

Lichen-forming fungi are mutualistic symbionts of green algae or cyanobacteria. We report the comparative analysis of six genomes of lichen-forming fungi in classes Eurotiomycetes and Lecanoromycetes to identify genomic information related to their symbiotic lifestyle. The lichen-forming fungi exhibited genome reduction via the loss of dispensable genes encoding plant-cell-wall-degrading enzymes, sugar transporters, and transcription factors. The loss of these genes reflects the symbiotic biology of lichens, such as the absence of pectin in the algal cell wall and obtaining specific sugars from photosynthetic partners. The lichens also gained many lineage- and species-specific genes, including those encoding small secreted proteins. These genes are primarily induced during the early stage of lichen symbiosis, indicating their significant roles in the establishment of lichen symbiosis.Our findings provide comprehensive genomic information for six lichen-forming fungi and novel insights into lichen biology and the evolution of symbiosis.

Taxol (Paclitaxel) and its derivative taxanes are widely used in chemotherapy and treatment of different types of cancer. Although the extracted taxanes from Taxus sp. are currently used in semi-synthetic production of Taxol, providing alternative always available sources is still a main concern. Due to availability and fast growth rate, microorganisms are much potent alternative sources for taxanes. In the present study, 249 endophytic fungi were isolated from Corylus avellana at six different locations of Iran, among which 18 species were capable to produce taxanes. Genotyping analysis indicated that 17 genera were ascomycetes but only one basidiomycete. Seven taxanes were detected and quantified in solid and suspension cultures by HPLC and their structures were confirmed by LC-Mass analysis. Among endophytes, CA7 had all 7 taxoids and CA1 had the highest Taxol yield. In 78% of endophytes transferring to liquid media was accompanied by increase of taxanes yield and increased taxan production and its release to media up to 90%. Evaluation of cytotoxicity indicated that extracts of all isolated fungi were lethal to MCF7 cells. Since endophytes produced remarkable amounts of taxanes, they can be suggested as alternative inexpensive and easily available resources for Taxol production in semi-synthesis plans.

Neoscytalidium novaehollandiae is one of the most important pathogens on woody plants which has increasingly been reported as a pathogen in different hosts in recent years. The pine trees are widely cultured in many cities of Iran. In recent years, dieback symptoms were observed on Pinus eldarica trees in Tehran and Qazvin provinces. The aim of this study was to investigate the dieback causal agent on P. eldarica trees in Iran. The branches and cones of P. eldarica trees were sampled for fungal isolation. The morphological and molecular characterizations (ITS, LSU, and TEF1-α regions) identified N. novaehollandiae as a dieback causal agent. This is the first report of N. novaehollandiae disease of P. eldarica trees in Iran. Furthermore, disease severity was assayed on 19 urban forest trees under three different temperature and relative humidity (RHs) regimes. C regime (29 °C and 15% RH) displayed more disease severity on detached branches than B (24 °C and 80% RH) and A (19 °C and 35% RH) ones. This study presents the host range of this pathogen, and showed that these potential hosts are prone to this pathogen under high temperature and low humidity which urban forest trees experienced in recent decades.

Symptoms of leaf blight, stem canker, and pod rot were observed on T. cacao during a series of samplings conducted in several states of Malaysia from September 2018 to March 2019. The identity of the pathogen that was responsible for the diseases was determined using morphological characteristics, DNA sequences, and phylogenetic analyses of multiple genes, namely, internal transcribed spacer (ITS), elongation translation factor 1-alpha (tef1-α), β-tubulin (tub2), and RNA polymerase subunit II (rpb2). A total of 57 isolates recovered from diseased leaves of T. cacao (13 isolates), stems (20 isolates), and pods (24 isolates) showed morphological features that resembled Lasiodiplodia sp. The identity of the isolates was further determined up to the species level by comparing DNA sequences and phylogenetic analyses of multiple genes. The phylogenetic analysis of the combined dataset of ITS, tef1-α, tub2, and rpb2 elucidated that all of the isolates obtained were Lasiodiplodia theobromae as supported by 97% bootstrap value. The results of pathogenicity tests revealed L. theobromae as the causal pathogen of leaf blight, stem canker, and pod rot of T. cacao.

Peyronellaea pinodes is a devastating pathogen of pea crop. Quantitative trait loci (QTL) associated with resistance have been identified, as well as genes differentially expressed between resistant and susceptible pea lines. The key question is which of these many genes located into these QTLs, or differentially expressed, are the key genes that distinguish resistant from susceptible plants and could be used as markers. To identify these key genes, in the present study we applied MACE (Massive Analysis of cDNA Ends) -Seq to a whole Recombinant Inbred Line population segregating for resistance to this disease and their parental lines and identified those genes which expression was more correlated with the level of resistance. We also compared gene expression profiles between the most resistant and the most susceptible families of the RIL population. A total of 6780 transcripts were differentially expressed between the parental lines after inoculation. Of them, 803 showed the same expression pattern in the bulks formed by the most resistant and most susceptible RIL families. These genes, showing a consistent expression pattern, could be used as expression markers to distinguish resistant from susceptible plants. The analysis of these genes also discovered the crucial mechanisms acting against P. pinodes., This study was supported by projects PID2020-114668RB-100 and EU-FP/-Legato, funded by MCIN/AEI/10.13039./5011000110033 and by European Research Council, respectively.