Search

Coffee production worldwide is affected by the pathogen Hemileia vastatrix, which causes the "coffee rust" disease and may be associated with other fungi. Ecuador lacks studies on fungal diversity associated with coffee rust, which could potentially control or escalate pathogen activity. Using the ITS-5.8S nrDNA region, we randomly detected a small preliminary fungi diversity related to coffee rust in Ecuador, which we report here for the first time. Ten coffee farms (four in Loja, three in Calvas, and three in Quilanga) from the Loja Province were sampled to analyze the genetic diversity of the pathogen Hemileia vastatrix in rust lesions on coffee leaves. A high number of selected sequences (Sanger sequencing) showed the presence of 48 OTUs (Operational Taxonomic Units) or "hypothetical species" of Ascomycetes and Basidiomycetes distributed across all the sampled farms. The genera Akanthomyces, Ceramothyrium, Cladosporium, Didymella, Fusarium, Mycosphaerella, Neoceratosperma, and Trichothecium of Ascomycetes, as well as Bulleribasidium, Hannaella, and Meira of Basidiomycetes, were the most abundant. To avoid taxonomic conflict, some sequences were placed into Capnodiales (Ascomycetes) and Tremelalles (Basidiomycetes) without a genus definition. A new phylogenetic group of sequences is considered Incertae Sedis from Basidiomycetes. Additionally, morphospecies of Akanthomyces (synonymous with some Lecanicillium species) and Colletotrichum were observed macroscopically and microscopically growing closely with rust. Most of the OTUs probably correspond to rust mycoparasites, as previously reported in the literature. However, this study is limited by the number of sequences analyzed phylogenetically, which may hinder the discovery of significant insights. Future studies are needed to determine whether this preliminary fungal diversity is associated with the rust fungus or corresponds to ubiquitous airborne fungi. Furthermore, research into the function of these species may reveal whether they promote rust pathogenicity or enhance plant responses by activating resistance mechanisms. [ABSTRACT FROM AUTHOR]

Pseudocercospora (previously Mycosphaerella) fijiensis is a hemibiotroph fungus and the causal agent of black Sigatoka disease, one of the most significant threats to banana production worldwide. Only a few genomics reports have paid any attention to effector proteins, which are key players in pathogenicity. These reports focus on canonical effectors: small secreted proteins, rich in cysteines, containing a signal peptide and no transmembrane domain. Thus, bias in previous reports has resulted in the non-canonical effectors being, in effect, excluded from the discussion of effectors in P. fijiensis pathogenicity. Here, using WideEffHunter and EffHunter, bioinformatic tools which identify non-canonical and canonical effectors, respectively, we predict, for the first time, the full effectorome of P. fijiensis. This complete effectorome comprises 5179 proteins: 240 canonical and 4939 non-canonical effectors. Protein families related to key functions of the hemibiotrophic lifestyle, such as Salicylate hydroxylase and Isochorismatase, are widely represented families of effectors in the P. fijiensis genome. An analysis of the gene distribution in core and dispensable scaffolds of both classes of effectors revealed a novel genomic structure of the effectorome. The majority of the effectors (canonical and non-canonical) were found to be harbored in the core scaffolds, while dispensable scaffolds harbored less than 10% of the effectors, all of which were non-canonical. Additionally, we found the motifs RXLR, YFWxC, LysM, EAR, [Li]xAR, PDI, CRN, and ToxA in the effectors of P. fijiensis. This novel genomic structure of effectors (more enriched in the core than in the dispensable genome), as well as the occurrence of effector motifs which were also observed in four other fungi, evidences that these phenomena are not unique to P. fijiensis; rather, they are widely occurring characteristics of effectors in other fungi. [ABSTRACT FROM AUTHOR]

As the number of livestock increased in the years following English colonisation of Australia in 1788, the need for nutritious fodder, including lucerne (Medicago sativa), grew. One of the first diseases found on lucerne was a leaf spot which was collected in 1879 by George Bancroft, a physician and naturalist, in a suburb of Brisbane. The Queensland Government Botanist Frederick Manson Bailey sent a specimen to the prominent English mycologists Miles Joseph Berkeley and Christopher Edmund Broome who in 1883 formally described and named the fungus Sphaerella destructiva. That fungus is now known as Pseudopeziza medicaginis , the causal agent of common leaf spot of lucerne. It was one of over 300 fungi that were included in a 1880 paper co-written by the Reverend Julian Tenison-Woods and Frederick Bailey. At that time almost all of these fungi which had been collected in Australia were identified by overseas mycologists, particularly Berkeley and Broome. It can be argued that their 1880 paper was the first significant one published in Australia which focussed on fungi. Just a decade or so later Australian scientists, in particular Daniel McAlpine, were describing new fungal taxa on their own. Among the fungi recorded in a paper published in the 1880 Proceedings of the Linnaean Society of New South Wales was Sphaerella destructiva , now Pseudopeziza medicaginis , the cause of common leaf spot of lucerne. The paper, co-authored by the naturalist Reverend Julian Tenison-Woods and the Queensland Government Botanist Frederick Manson Bailey was the first known comprehensive list of Australian fungi published by Australian residents. It is a milestone in the evolution of mycology and plant pathology studies in Australia. Photograph by H. H. Baily. [ABSTRACT FROM AUTHOR]

Leaf spot or yellow sigatoka disease (caused by Mycosphaerella musicola) of banana causes significant yield loss as well as in quality of fruits in every year and reported up to 65% or even more under favorable epidemic conditions. In this perspective, an experiment was conducted at ZBNF project Research field, college of horticulture, Sirsi (Uttara Kannada district of Karnataka) for consecutive two seasons (2020-21 & 2021-22). Experiment accompanied with RBD statistical design with five replications and four treatments. Four different management practices involving viz. Propiconazole 25EC @ 0.1% (Recommended package of practices-UHS, Bagalkot), Trichoderma harzianum 10g/lit. (Organic farming), sour butter milk 5 lit. per 200 liter of water (Natural farming) and Tebuconazole 50% + Trifloxystrobin 25% WG @0.5gm/lit. (Chemical farming) were evaluated against sigatoka leaf spot disease. Among the management practices, chemical farming comprises tebuconazole 50%+ trifloxystrobin 25%WG@1gm/lit was found effective in managing the disease (12.38% PDI) followed by recommended package of practice comprises propiconazole 25%EC @1ml/l (16.33% PDI), organic farming comprises of talk-based Trichoderma harzianum 10g/lit (17.33% PDI). Natural farming showed least effective to combat disease recorded maximum disease severity (19.66% PDI) after 210 days after planting. Although chemical farming can effectively control the disease but results in the serious risk on human health and environmental hazards. Therefore, organic and natural farming are an alternative approach that are eco-friendly and economically viable against sigatoka leaf spot disease management. [ABSTRACT FROM AUTHOR]

Objective: To establish the favorable or unfavorable climatic conditions for the emergence and development of Black Sigatoka in a banana-growing area within the influence zone of the Teapa weather station (27004) in Tabasco, Mexico. Design/Methodology/Approach: We analyzed temperature data for n=59 years (1961-2019) at the Teapa weather station (27044) in Tabasco, as reported by IMTA (2009) and the Servicio Meteorológico Nacional (until 2019). Relative humidity was calculated using the equation developed by Allen et al. (2006). We also established the favorable or unfavorable climatic conditions for the development of Black Sigatoka in Teapa by resorting to the favorability typology posited by Júnior et al. (2008). Results: There are no highly favorable climatic conditions for the incidence and development of this disease. Overall, spring and summer are the less favorable months, while fall and winter offer more favorable conditions. Study Limitations/Implications: This study should be replicated in other banana-growing areas of Tabasco, since both temperature and relative humidity may differ and, consequently, the frequency of the disease may vary. Findings/Conclusions: October and March are the most favorable months for Black Sigatoka occurrence. Therefore, comprehensive management and control programs should be designed for this period. [ABSTRACT FROM AUTHOR]

Agronomic performance of banana cultivars varies according to each ecological zone. Sigatoka disease complex causes severe economic losses to banana growers. Climate conditions associated to genotypes of banana plants influence several agronomic traits related to this disease. The objective of this study was to evaluate the agronomic performance of banana cultivars naturally infected with Mycosphaerella sp. under subtropical conditions. Severity of Sigatoka disease complex and agronomic performance of nine cultivars were evaluated during three successive productive cycles. Tetraploid hybrids showed lower cycle from seedling to harvest, disease severity and higher number of leaves at harvest. Pomme and Cavendish subgroups were more susceptible to Sigatoka disease complex and had lower numbers of leaves at the harvest. 'BRS SCS Belluna' showed moderate susceptibility to Sigatoka disease complex. 'FHIA 1' and 'Nanicão' produced the heaviest bunch. Path analysis showed that Sigatoka disease complex can negatively affect bunch weight for two consecutive cropping cycles. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant resistance inducers, such as plant-growth-promoting rhizobacteria (PGPR), are among the most important alternatives to fungicides because they employ different modes of action, conferring protection against biotic and abiotic stresses while promoting plant growth. However, the loss of their efficacy under field conditions is a subject of debate and may be attributed to the influence of environmental factors, genetic diversity and native soil microbial communities. Additionally, the inoculation of plants with PGPR can impact the complex and dynamic balance of soil microbial communities. Recently, we published the efficiency of three PGPR in single and co-inoculation to induce wheat resistance mechanisms against Septoria leaf blotch and drought stress. Here, we investigated the interactions between PGPR and soil microbial communities. The efficiency of plant-growth-promoting rhizobacteria (PGPR) may not be consistently maintained under field conditions due to the influence of soil microbial communities. The present study aims to investigate their impact on three PGPR-based biofertilizers in wheat. We used the PGPR Paenibacillus sp. strain B2 (PB2), PB2 in co-inoculation with Arthrobacter agilis 4042 (Mix 2), or with Arthrobacter sp. SSM-004 and Microbacterium sp. SSM-001 (Mix 3). Inoculation of PB2, Mix 2, and Mix 3 into non-sterile field soil had a positive effect on root and aboveground dry biomass, depending on the wheat cultivar. The efficiency of the PGPR was further confirmed by the protection they provided against Mycosphaerella graminicola, the causal agent of Septoria leaf blotch disease. PB2 exhibited protection of ≥37.8%, while Mix 2 showed ≥47.9% protection in the four cultivars tested. These results suggest that the interactions between PGPR and native soil microbial communities are crucial for promoting wheat growth and protection. Additionally, high-throughput sequencing of microbial communities conducted 7 days after PGPR inoculations revealed no negative effects of PB2, Mix 2, and Mix 3 on the soil microbial community structure. Interestingly, the presence of Arthrobacter spp. appeared to mitigate the potential negative effect of PB2 on bacterial community and foster root colonization by other beneficial bacterial strains. [ABSTRACT FROM AUTHOR]

One of the most devastating foliar diseases of wheat worldwide is Septoria leaf blotch (STB), caused by Mycosphaerella graminicola (asexual stage/Anamorph: Septoria tritici) which has been recently intensified in some regions in Iran. In this study, 49 wheat genotypes and 20 wheat differential genotypes were evaluated for their reaction to infection by six isolates of M. graminicola collected from infected fields during 2016–2017 at seedling stage under greenhouse conditions. According to the analysis of variance (ANOVA) of leaf pycnidia coverage percentage, a significant difference (p <.01) was observed between M. graminicola isolates and wheat cultivars. The interaction between genotypes and isolates was also significant (p <.01) and the results indicated a specific interaction between genotypes and isolates. The results presented Dezful and West Azerbaijan isolates that were the most virulent with more pathogenesis on differential genotypes. Although 47 of the wheat genotypes were susceptible to all isolates, some genotypes, including Wc‐46,224 (Austria), Wc‐45,425 (Portugal), Wc‐45,565 (Turkey), P.S.No4 (Italy), Dehdasht, M3 Synthetic, KavKaz‐k4500, Arina, Flame, and Riband were resistant to all isolates. In addition, the isolates exhibited different virulence patterns on wheat genotypes. The results of this study revealed high virulence of M. graminicola isolates, and Iranian and foreign wheat genotypes, commonly used in the region, presented high susceptibility, and the resistance sources had been identified among genotypes that can be applied in the wheat breeding programs. [ABSTRACT FROM AUTHOR]

Banana Black Sigatoka (BBS) is the most threatening and production-limiting factor for banana worldwide. A total of 330 banana fields were assessed from two districts in southern Ethiopia during 2020 and 2021 to determine the distribution and association of BBS severity with agronomic practices and environmental factors. Meteorological variables were obtained from the nearby meteorological stations. The results showed that BBS was prevalent across surveyed areas, with varying degrees of severity. Higher BBS severity was recorded in Mihirab Abaya (66.82 ± 1.47%) than Arba Minch (58.03 ± 1.39%) district. The logistic regression model was used to explain the association of disease severity with independent variables. District, year, time of assessment, moisture source, source of plant material, banana cultivar, growth stage, cropping pattern, nutrient, sucker and disease management, weed infestation, and other agronomic practices were significantly (P < 0.05 to 0.001) associated with BBS severity of > 50% in the multiple-variable model. Lower (≤ 50%) disease severity was strongly associated with Pisang Sri cultivar, vegetative stage, ≤ 5 years of plantation, row planting, mixed cropping, low plant density and weed infestation, and good nutrient (KCl at ≤ 385 kg ha–1), sucker (≤ 5 plants spot–1), disease and other agronomic managements than other class variables. Moreover, high precipitation and humidity, low temperature, rain-wash, and water splash were also identified as the most important driving forces for BBS infection and establishment. Thus, cultivar resistance, mixed cropping, row planting, optimal plant density, good nutrient, sucker and weed management, complete earthing up, and better irrigation and drainage practices should be considered as management options. [ABSTRACT FROM AUTHOR]

Introduction-- The strawberry crop is seriously affected by different diseases that result in a decrease in production and fruit quality. Among the most important diseases that attack the strawberry crop is Mycosphaerella fragariae, the causal agent of leaf spot, which in advanced stages can lead to the total loss of the crop. Monitoring of this disease is a fundamental tool for its prevention and control. The tools of precision agriculture and agriculture 4.0, such as images obtained by drones, facilitate decision making by producers and optimize crop work such as monitoring. Objetive-- This study identified the relationship between the percentage of area affected by leaf spot (Mycosphaerella fragaraiae), the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Red Edge Index (NDRE). Metodology-- The study was developed in the province of Pamplona in Norte de Santander with high inoculum pressure of Mycosphaerella fragariae. Leaflets were collected from strawberry plants with different degrees of affectation caused by Mycosphaerella fragariae, this plant material was transported guaranteeing its conservation until the laboratory, where measurements were made with the Stellar Net brand EPP2000 portable spectroradiometer, from which the values of the red band, infrared and the red border of each one was taken to perform the calculation of NDVI and NDRE, these values were averaged for each degree of affectation. The exact affected area was calculated for each leaf using the Compu eye leaf and symptom area software and the correlation coefficients were calculated looking for a mutual linear relationship from simple linear regressions. Results-- The NDRE index correlates 82% with the area affected by Mycosphaerella fragariae by up to 70%. Conclusión-- The percentage of area affected by leaf freckle (Mycosphaerella fragariae) is directly related to the spectral response in terms of NDVI and NDRE indices, The spectral behavior of the leaf freckle (Mycosphaerella fragariae) in the strawberry crop has a linear behavior with respect to the NDVI and NDRE indices, where in the initial stages of the disease the values of the indices are close to zero, and as it progresses disease indices show a decrease in their values. There is a greater degree of correlation between the percentage of the affected area and the NDRE index up to 70% of the affected area, because this is more sensitive to the change in the chlorophyll content of the leaf. [ABSTRACT FROM AUTHOR]

Most research on the human microbiome focuses on the bacterial component, and this has led to a lack of information about the fungal component (mycobiota) and how this can influence human health, e.g., by modulation through the diet. The validated, dynamic computer-controlled model of the colon (TIM-2) is an in vitro model to study the microbiome and how this is influenced by interventions such as diet. In this study, it was used to the study the gut fungal-community. This was done in combination with next-generation sequencing of the ITS2 region for fungi and 16S rRNA for bacteria. Different dietary interventions (control diet (SIEM), high-carbohydrate, high-protein, glucose as a carbon source) were performed, to see if diet could shape the mycobiome. The mycobiome was investigated after the adaptation period, and throughout the intervention period which lasted 72 h, and samples were taken every 24 h. The fungal community showed low diversity and a greater variability when compared to bacteria. The mycobiome was affected most in the first hours of the adaptation period. Taxonomic classification showed that at the phylum-level Ascomycota and Basidiomycota dominated, while Agaricus, Aspergillus, Candida, Penicillum, Malassezia, Saccharomyces, Aureobasidium, Mycosphaerella, Mucor and Clavispora were the most abundant genera. During the intervention period, it was shown that the change of diet could influence the diversity. Clustering of samples for different time points was analyzed using Bray–Curtis dissimilarities. Samples of t0 clustered together, and samples of all other time points clustered together. The Bray–Curtis-dissimilarity analysis also showed that for the different dietary interventions, samples treated with glucose clustered together and were different from the other groups (p < 0.05, PERMANOVA). Taxonomic classification showed that the genera Alternaria, Thanatephorus, Candida and Dekkera differentially changed for the various diet groups (p < 0.05, Kruskal–Wallis). These results show that the mycobiota could be modelled in TIM-2; however, the low diversity and high variability make studying fungal, as compared to bacterial, communities, much more challenging. Future research should focus on the optimization of the stability of the fungal community to increase the strength of the results. [ABSTRACT FROM AUTHOR]

In this study, the micromorphology and surface details of Pseudocercospora pseudostigmina‐platani conidia were investigated on American sycamore (Platanus occidentalis) leaves. Sooty films were collected from diseased leaves for fungal DNA extraction and observed using light and field‐emission scanning electron microscopy. Two types of conidia were present on the leaves: (i) hyaline and curved Cercostigmina‐like conidia and (ii) brown and straight Stigmina‐like conidia. The fungal pathogen was identified as P. pseudostigmina‐platani based on morphological characteristics and internal transcribed spacer region sequences. Some non‐glandular trichomes were found near the centre of the conidial masses on the abaxial surface of the naturally infected leaves. Leaf ultrasonication to dislodge conidia revealed sporodochia erupting through the stomata. Hyphae from sporodochia grew on the leaf surface and entered host tissues through the stomata. Conidiogenous cells had terminal rings and tapered towards the flat region where a conidium was attached. The conidia produced secondary conidia directly without hyphae. After dislodging the conidia by ultrasonication, scars were observed. These results indicate that the fungus has dimorphic conidia and microcycle conidiation for simple and rapid asexual reproduction. [ABSTRACT FROM AUTHOR]

Yellow and black Sigatoka, caused by Mycosphaerella fijiensis and M. musicola, respectively, are the most important worldwide foliar diseases of bananas. Disease control is heavily dependent on intensive fungicide sprays, which increase selection pressure for fungicide resistance in pathogen populations. The primary objective of this study was to assess the level and spread of resistance to quinone-outside inhibitors (QoI—strobilurin) fungicides in populations of both pathogens sampled from banana fields under different fungicide spray regimes in Southeastern Brazil. Secondly, we aimed to investigate when QoI resistance was confirmed if this was associated with the target-site alteration G143A caused by a mutation in the mitochondrial encoded cytochrome b gene. QoI resistance was detected in fungicide treated banana fields, while no resistance was detected in the organic banana field. A total of 18.5% of the isolates sampled from the pathogens' populations were resistant to QoI. The newly described M. thailandica was also found. It was the second most abundant Mycosphaerella species associated with Sigatoka-like leaf spot symptoms in the Ribeira Valley and the highest level of QoI resistance was found for this pathogen. The G143A cytochrome b alteration was associated with the resistance to the QoI fungicides azoxystrobin and trifloxystrobin in M. fijiensis, M. musicola and M. thailandica strains. In order to reduce resistance development and maintain the efficacy of QoI fungicides, anti-resistance management strategies based on integrated disease management practices should be implemented to control the Sigatoka disease complex. [ABSTRACT FROM AUTHOR]

Aim: To obtain promising immunosuppressants from endophytic fungus. Methods and Results: The endophytic fungus Mycosphaerella nawae (ZJLQ129) was isolated from the plant Smilax china L. and its secondary metabolites extracted and fractionated through column chromatography. The metabolites were further modified by a derivatization reaction with ammonium hydroxide. After isolation and derivatization, a new dibenzofuran named as (+)isomycousnine enamine (iME) was obtained. The structures of the derivatives were determined based on chemical evidences and extensive spectroscopic methods including 2D‐NMR, DEPT and HRESI‐MS spectra. The immune activities of iME were first evaluated on the proliferation and cytokines (IL‐2 and IFN‐γ) production of T and B cells by using MTT and ELISA methods respectively. Then, its effects on the proliferation of T‐cell subsets (CD4+ and CD8+ T cells), as well as CD25 and CD69 expressions were also determined by flow cytometry. Finally, by using Cytometric Bead Array (CBA), the impacts of iME on the secretion of Th1/Th2/Th17 cytokines from purified CD4+ T cells were assayed. The results showed that iME not only selectively suppressed the immune responses of T cells, but also preferentially inhibited the activation and proliferation of CD4+ T cells. Conclusion: A novel dibenzofuran derived from endophytic fungus Mycosphaerella nawae preferentially inhibits CD4+ T‐cell activation and proliferation. Significance and Impact of the Study: This work obtained iME, a new dibenzofuran derived from endophytic fungus. iME has the capacity to inhibit CD4+ T‐cell activation and therefore is a novel potential immunosuppressant for development in the future. [ABSTRACT FROM AUTHOR]

In order to discover more promising anti-fungal agents, a series of benzoxazole family was synthesized by PPA-catalyzed condensation and a Raney nickel/hydrazine reduction. Altogether 45 compounds were obtained in good to excellent yields and characterized by FT-IR, NMR, MS, and X-ray crystal diffraction. Moreover, the biological activity against eight phytopathogenic fungi was investigated. All in all, most of these compounds bear moderate antifungal activities. Among them, three candidates show the strongest activities, compound 4ac, 4bc provided over 50% inhibition rate against five fungi. Especially, the inhibitory rate of compound 4ah on Mycosphaerella melonis reached 76.4%. [ABSTRACT FROM AUTHOR]

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The adoption of monitoring systems to control the Sigatoka disease complex represents one of the most significant advances in banana production worldwide. In this paper four methodologies for evaluating Yellow Sigatoka (Biological Pre Warning - BPW, Stage of Evolution - SE, Infection Index - II, and Youngest Leaf Spotted - YLS) were compared under experimental conditions, and two methods were selected for commercial orchards in subtropical conditions. These monitoring systems were submitted to correlation (P

This paper contains results of investigation of the most important fungi found on wych elm (Ulmus glabra) trees in Montenegro. During the monitoring, 21 fungal species were found on wych elm (Ulmus glabra) in Montenegro. Fungus Ophiostoma novo-ulmi was the most frequent on young trees while species Fomes fomentarius and Daldinia concentrica were the most frequent on old trees. Fungi Mycosphaerella ulmi and Stegophora ulmea were the most common species on leaves. Majority of fungi in this study was for the first time recorded on wych elm (Ulmus glabra) in Montenegro. Obtained results will contribute to knowing about fungi associated with Dutch elm disease as well as fungi colonizing healthy trees left to spontaneous growth. [ABSTRACT FROM AUTHOR]

Copyright of Montes is the property of Colegio y Asociación de Ingenieros de Montes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AAC Aberdeen is a semi-leafless, yellow cotyledonary field pea (Pisum sativum L.) cultivar developed at Lacombe Research and Development Centre, Agriculture and Agri-Food Canada, Lacombe, AB, Canada. It has a maturity of 98days, 1000-seed weight of 243g, and a lodging score of 3.3 on the scale of 1–9. The seed crude protein content of AAC Aberdeen is 20.1%. AAC Aberdeen is resistant to powdery mildew (caused by Erysiphe pisi D.C.) and moderately susceptible to mycosphaerella blight (caused by Mycosphaerella pinodes) and Fusarium root rot (caused by Fusarium avenaceum (Fr.) Sacc.). [ABSTRACT FROM AUTHOR]

The objective of the study was to isolate fungi from healthy and wilt banana in order to understand their diversity as well as their physiological characters to produce growth hormone and solubilize inorganic phosphate. The fungi were isolated from the leaves, roots, and rhizosphere of the banana. As many 13 fungal isolates were associated with wilt banana, consisted of Fusarium, Trichoderma, Bipolaris, Colletotrichum, Clonostachys, and Talaromyces genus. On the other hand, 12 fungal isolates that belong to 10 genera related to the healthy banana have been isolated, including Trichoderma, Pallidocercospora, Purpureocillium, Pallidocercospora, Mycosphaerella, Chaetomium, Neonectria, Pararamichloridium, Xylaria, and Neocordana. We found that the fungal isolates associated with wilt banana, particularly from the Fusarium genus, actively produced IAA in the presence of exogenous L-Tryptophan have high ability to solubilize insoluble phosphate. The ability of fungal isolates to solubilize insoluble phosphate was correlated with their ability to acidify the medium. Supplemental data for this article is available online at . [ABSTRACT FROM AUTHOR]

Purpose of the study: Marine fungi of Mauritius have been poorly studied. There are numerous reports on the bioactive secondary metabolites that are produced by fungi around the world. Yet, research on the molecular characterisation and the pharmaceutical potential of marine fungi in Mauritius is rather scanty. Method: The samples, which consisted of three sponges Haliclona sp., Iotrochota sp. and Biemna sp. and two brown algae Turbinaria conoides and Sargassum portierianum, were collected in the North of Mauritius during winter. No sporulating structures were observed from the fungal cultures making morphological analysis impossible. The molecular characterisation of the selected isolates was carried out by the amplification of the ITS regions and phylogenetic analysis. The antimicrobial properties were then determined using the disc diffusion and the minimum inhibitory concentration (MIC) assay. Results: Genus level identification was made from molecular data and for some isolates, species-level identification was even possible. Twelve fungi that showed the best antimicrobial properties were identified as Peniophora sp., Aspergillus cristatus, Acremonium sp., Cordyceps memorabilis, Aspergillus ochraceus, Biscogniauxia sp., Aspergillus keratitidis, Exserohilum rostratum, Chromocleista sp., Nigrospora oryzae, Aspergillus flavipes and Mycosphaerella. The lowest MIC result of 0.0098 mg/mL was obtained with Chromocleista sp. mycelium extract against Staphylococcus aureus. The MIC of the mycelium extracts was lower than the broth extracts for most isolates indicating that the antimicrobial compounds are not secreted. Conclusion: Marine fungi from the Mauritian waters have immense potential in the search for natural products against antibiotic-resistant bacteria. [ABSTRACT FROM AUTHOR]

Mycosphaerella blight, caused by Peyronellaea pinodes (Berk. & A. Bloxam) Aveskamp, Gruyter & Verkley (syn. Mycosphaerella pinodes (Berk. et Blox.) Vesterg.), is a destructive foliar pathogen of field pea that is managed, in large part, through application of foliar fungicide at flowering. The fungicides are usually applied into dense crop canopies, so reaching the lower areas of the canopy where the pathogen is initially most active is a challenge. Field trials were conducted across the Canadian prairies from 2008 to 2011 to assess the efficacy of various nozzle numbers and orientations, droplet sizes, and water volumes for the management of Mycosphaerella blight to increase yield in field pea. Pea plants were assessed for disease severity during flowering and seed yield was measured. In 10 of the 13 trials, double-nozzle configurations provided a 15% reduction in disease severity and up to a 60% increase in yield. In contrast, droplet size and angle of application had no effect on field pea yield. Water volume trials using up to 400 L ha−1 improved fungicide efficacy relative to control treatments, however, volumes above 400 L ha−1 resulted in high-disease severity and lower yield, likely as a result of fungicide run-off due to saturation of the leaf surface. When deciding on effective sprayer techniques for fungicide application, disease pressure, environmental conditions and cultivar characteristics are important to consider. [ABSTRACT FROM AUTHOR]

Reports on fungi occurring on marine crabs have been mostly related to those causing infections/diseases. To better understand the potential role(s) of fungi associated with marine crabs, this study investigated the culturable diversity of fungi on carapace of the marine shallow-water hydrothermal vent crab Xenograpsus testudinatus collected at Kueishan Island, Taiwan. By sequencing the internal transcribed spacer regions (ITS), 18S and 28S of the rDNA for identification, 12 species of fungi were isolated from 46 individuals of X. testudinatus: Aspergillus penicillioides, Aspergillus versicolor, Candida parapsilosis, Cladosporium cladosporioides, Mycosphaerella sp., Parengyodontium album, Penicillium citrinum, Penicillium paxili, Stachylidium bicolor, Zasmidium sp. (Ascomycota), Cystobasidium calyptogenae and Earliella scabrosa (Basidiomycota). With additional data from other published reports, a total of 26 species of fungi (23 Ascomycota, three Basidiomycota) have been recorded from X. testudinatus. Aspergillus is the most speciose genus on the crab, followed by Penicillium and Candida. All but one species (Xylaria arbuscula) had been previously isolated from substrates in the marine environment, although many are typical terrestrial taxa. None of the recorded fungi on X. testudinatus are reported pathogens of crabs, but some have caused diseases of other marine animals. Whether the crab X. testudinatus is a vehicle of marine fungal diseases requires further study. [ABSTRACT FROM AUTHOR]

In a first step, essential oils were extracted from Eucalyptus globulus leaves, healthy and with symptoms and signs of Mycosphaerella leaf disease (MLD) and Teratosphaeria leaf disease (TLD), in two leaf stages. Stage 1: sessile, oval leaves covered by a waxy layer of a bluish colour, with opposite phyllotaxis, inserted along stems of quadrangular section. Stage 2: narrow and sickle leaves with a greyish green surface, mainly on the abaxial surface, inserted in alternating pairs along rounded stems. The essential oils were extracted by hydrodistillation and were analyzed by gas chromatography coupled with mass spectrometry. Chemical composition data and percentages of essential oil constituents were submitted to cluster analysis and principal component analysis. In a second step, under in vitro conditions, was evaluated the germination of Teratosphaeria nubilosa (one of the causal agents of TLD) ascospores in contact with the four types of essential oils extracted. The evaluations were performed at 24, 48 and 72 h after the experiments were assembled. The present study made it possible to distinguish and identify the chemical composition of essential oils from the eucalypt leaves used, and allowed 1,8-cineole to be identified as the major component for the essential oils investigated. The contact between essential oils and T. nubilosa spores allowed to prove the inhibition of the ascospores germination, being more efficient for the essential oils extracted from materials with the disease, which presented high amounts of 1,8-cineole. [ABSTRACT FROM AUTHOR]

Plant extracts and oils were assessed for strawberry leaf spot control in organic strawberry in the open field. For first cycle, treatments were extracts of rosemary (10 %) (Rosmarinus officinalis L.), garlic (Allium sativum L.) (0.01 %), rue (Ruta graveolens L.) (10 %), turmeric (Curcuma longa L.) (1 %), Bordeaux mixture (1 %), cotton (1.5 %) and canola oils (1 %), and water (control). For second cycle, Rosemary (20 %), rue (20 %), turmeric (2 %), canola oil (2 %), and water were used as treatments. A completely randomized block design with five replications was used. An analysis of variance was performed on the severity data, AUDPC and fruit production means were compared by the Scott-Knott and Tukey tests at 5 % probability for first and second cycles, respectively. Canola oil (1 and 2 %) reduced disease symptoms in both cycles. Rosemary and rue extracts reduced just when disease severity was low. Cotton and canola oils and rosemary, rue and turmeric extracts increased strawberry fruit production. [ABSTRACT FROM AUTHOR]

Deep-sea sediments are now recognized as a home for rich and largely microbial community. Recently, it has been believed in an increasing number of studies that bacteria could be abundant in deep-sea sediments of many types; however, fungi in deep-sea sediments remain relatively unknown. The phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough sediments were investigated in traditional method combined with fungal identification of molecular biology in this study. A total of 76 isolates belonged to 15 fungal taxa were recovered in a harsh condition of low nutrient and low temperature, indicating that the fungal communities in deep-sea sediments from Okinawa Trough were relatively abundant and diversified. Aspergillus, Cladosporium, and Penicillium were the dominant fungal genera, while Mycosphaerella, Purpureocillium, and Schizophyllum were relatively rare in the deep-sea sediments from Okinawa Trough. Among the six genera recovered, Mycosphaerella was firstly recovered from deep-sea sediments in this study. Moreover, about 75% of the extracts from the 15 fungal representative isolates displayed distinct bioactivity against at least one indicator bacterium or marine macrofouler, emphasizing the potentials of these deep-sea-derived fungi from Okinawa Trough as producers of bioactive metabolites. Notably, isolates Cladosporium oxysporum SCSIO z001 and Penicillium citrinum SCSIO z049 displayed a wide spectrum of bioactivities, isolates Cladosporium cladosporioides SCSIO z015, Cladosporium sphaerospermum SCSIO z030, and Penicillium verruculosum SCSIO z007 exhibited a strong anti-bacterial-growth activity, and isolate Penicillium chrysogenum SCSIO z062 displayed a strong anti-larval-settlement activity. These results suggest that these isolates deserved further study as potential sources of novel bioactive metabolites. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dothistroma septosporum, the primary causal agent of Dothistroma needle blight, is one of the most significant foliar pathogens of pine worldwide. Its wide host and environmental ranges have led to its global success as a pathogen and severe economic damage to pine forests in many regions. This comprehensive global population study elucidated the historical migration pathways of the pathogen to reveal the Eurasian origin of the fungus. When over 3800 isolates were examined, three major population clusters were revealed: North America, Western Europe, and Eastern Europe, with distinct subclusters in the highly diverse Eastern European cluster. Modeling of historical scenarios using approximate Bayesian computation revealed the North American cluster was derived from an ancestral population in Eurasia. The Northeastern European subcluster was shown to be ancestral to all other European clusters and subclusters. The Turkish subcluster diverged first, followed by the Central European subcluster, then the Western European cluster, which has subsequently spread to much of the Southern Hemisphere. All clusters and subclusters contained both mating-types of the fungus, indicating the potential for sexual reproduction, although asexual reproduction remained the primary mode of reproduction. The study strongly suggests the native range of D. septosporum to be in Eastern Europe (i.e., the Baltic and Western Russia) and Western Asia. [ABSTRACT FROM AUTHOR]

We performed a 3‐year field survey in France to characterize the dynamics of sexual reproduction in Mycosphaerella linicola, the causal agent of pasmo, during the interepidemic period. Cohorts of fruiting bodies were sampled from linseed straw during the autumn and winter and carefully observed, focusing on pseudothecia, asci, and ascospores. A sequence of experimental steps corresponding to Koch's postulates confirmed in July 2014, for the first time in France and continental Europe, the widespread presence of the sexual stage of M. linicola in plant host tissues. The developmental dynamics of pseudothecia on straw, expressed as the change over time in the percentage of mature pseudothecia, was similar in all three years. Pseudothecia appeared in late summer, with peak maturity reached in October. A temporal shift, thought to be due to early autumn rainfall, was highlighted in one of the three years. These observations suggest that sexual reproduction plays a significant role in the epidemiology of pasmo in France. A resurgence of M. linicola infections in spring flax is thought to have occurred in recent years, due to the increase in the area under flax. The presence of the sexual stage of this pathogen probably increased the quantitative impact of residues of winter linseed (used for oil) and flax straw (left on the soil for retting and used for fibres) as an interepidemic "brown bridge". This case study highlights how certain parts of a disease cycle, in this case the sexual phase, can become crucial due to changes in production conditions. [ABSTRACT FROM AUTHOR]

Background: Little is known about intestinal fungi in IBS patients whose gut bacteria have been investigated a lot. In order to explore causal relationship between IBS and gut mycobiome, and use gut fungi to diagnose or even treat IBS, further characterization of it in IBS is required. Methods: Fifty‐five diarrhea‐predominant IBS (D‐IBS) patients fulfilling Rome III criteria, and 16 healthy controls (HC) were recruited. Fresh fecal samples were collected and used for 16s rRNA and ITS2 high‐throughput sequencing. Diversity and composition of gut bacteria and fungi, as well as bacterial‐fungal interactions in D‐IBS patients, were characterized. Specific fungal taxa differentiating D‐IBS from HC were recognized by LEfSe and RandomForest methods, and their association with clinical symptoms was assessed by Spearman's correlation. Results: Diarrhea‐predominant irritable bowel syndrome patients showed abnormal (IBS‐dysbiosis) or normal (HC‐like IBS) fecal bacterial structure and diversity compared with healthy controls. However, fecal fungal signatures differed absolutely between D‐IBS and HC, which indicated a more susceptible alteration of gut fungi than bacteria in D‐IBS. Fecal fungi showed significant correlations with IBS symptoms, especially Mycosphaerella, Aspergillus, Sporidiobolus, and Pandora which were identified to potentially differentiate D‐IBS from HC. Moreover, compared with HC there were markedly declined bacterial‐fungal interactions in D‐IBS, in which Candida changed from negative to positive correlations with bacteria, and Eurotium changed from positive correlations to irrelevance, while Debaryomyces gained negative correlations with bacteria. Conclusions: Gut fungal dysbiosis and altered bacterial‐fungal interactions were present in patients with D‐IBS, and gut fungi could be used to diagnose D‐IBS. [ABSTRACT FROM AUTHOR]

Copyright of Mediterranean Agricultural Sciences is the property of Akdeniz Universitesi Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sigatoka leaf diseases are a major constraint to banana production. A survey was conducted in Tanzania and Uganda to assess the distribution of Pseudocercospora species and severity of Sigatoka leaf diseases. Pseudocercospora species were identified using species‐specific primers. Sigatoka‐like leaf diseases were observed in all farms and on all cultivars, but disease severity varied significantly (P < 0.001) between countries, districts/regions within countries, altitudinal ranges and banana cultivars. In all regions except Kilimanjaro, P. fijiensis, the causal agent of black Sigatoka, was the only pathogen associated with Sigatoka disease. Mycosphaerella musae was associated with Sigatoka‐like symptoms in Kilimanjaro region. Black Sigatoka disease was more severe in Uganda, with a mean disease severity index (DSI) of 37.5%, than in Tanzania (DSI = 19.9%). In Uganda, black Sigatoka disease was equally severe in Luwero district (mean DSI = 40.4%) and Mbarara district (mean DSI = 37.9%). In Tanzania, black Sigatoka was most severe in Kagera region (mean DSI = 29.2%) and least in Mbeya region (mean DSI = 11.5%). Pseudocercospora fijiensis, the most devastating sigatoka pathogen, was detected at altitudes of up to 1877 m a.s.l. This range expansion of P. fijiensis, previously confined to altitudes lower than 1350 m a.s.l. in East Africa, is of concern, especially for smallholder banana farmers growing the susceptible East African Highland bananas (EAHB). Among the banana varieties sampled, the EAHB, FHIA hybrids and Mchare were the most susceptible. Here, the loss of resistance in Yangambi KM5, a banana variety previously resistant to P. fijiensis, is reported for the first time. [ABSTRACT FROM AUTHOR]

Fusarium wilt disease and Sigatoka leaf spots threaten global market of Musa sp. Major Intrinsic Proteins (MIP) consisting aquaporins (AQPs) facilitate the transport of water and molecules like H2O2, CO2, silicon, boron, urea, and ammonia. Biotic and abiotic stresses affect the expression level of MIPs and influence the transportation of water and nutrients, which results in the susceptibility of plants to diseases. Expression level of MIP genes in Musa acuminata (MaMIPs) fruits during development and under acetylene treatment; expression of MaMIPs in the corms of banana infected with Fusarium oxysporum cubense (Foc), and the expression of MaMIP genes in the leaves treated with Mycosphaerella fijiensis were retrieved from the banana genome hub database. Expression data of roots, treated with virulent Focs at 3, 27, and 51 hours post-inoculation (hpi) were downloaded from Gene Expression Omnibus. The expression data were analyzed using MeV 4.9 program. Expression level of MaMIPs was mainly suppressed by acetylene and biotic treatments. Twenty seven and 51 hpi of roots with Foc, 88% and 63% of MaMIPs were down-regulated. However, MaNIP2-1 expression showed a significant up-regulation in all conditions. Infection of banana corms resulted in the suppression of MaMIPs. A low decrease in the expression of MaMIPs was observed, when the leaves were under Mycosphaerella fijiensis attack. Suppression of MaMIPs might be in line with repression of plant defense by banana pathogens as an approach for infection progression. Identification of the MIPs influenced by stresses provides the opportunity for the production of transgenic resistant cultivars.

Mycosphaerella leaf disease (MLD) is a pathogen of eucalypt plantations causing leaf spots and defoliation, and affecting growth. In this study, two different dosages of nitrogen fertilisation together with a control treatment currently used for two clones being affected by MLD (C18 and C25) of Eucalyptus dunnii were tested. We measured root collar diameter (D) and height (H), and assessed disease severity in the apical, middle and basal portions of the crown at planting, three months after planting and five months after planting, and determined the Area Under Disease Curve Progress at the end of the study, for the following fertilisation treatments: reduced dosage 22.0 kg ha−1 of NH4NO3; control dosage 44.0 kg ha−1 of NH4NO3; and increased dosage 66.0 kg ha−1 of NH4NO3. We added 133.4 kg ha−1 of P2O5 and 28.0 kg ha−1 of KCl to each treatment. MLD severity was higher in the basal portion of the crown. Only for C18 did the control dosage and the increased dosage promote growth in root collar diameter and reduce MLD severity, respectively. For C25 there were no differences for the variables across the fertilisation treatments. For C18 correlation analysis indicated that increased nitrogen dosage reduced MLD severity (r = 0.83; p < 0.01). In conclusion, improved nitrogen fertilisation proved to be effective to reduce severity, but differences were observed between clones and fertilisation. [ABSTRACT FROM AUTHOR]

In field and laboratory experiments during 2014–2017, we investigated the influence of lower and higher cultivation intensity of wheat and ecological factors (weather—temperature and rainfalls, year) on the occurrence of phytopathogenic fungi on the leaves of winter wheat. The prevailing fungi in those years were Mycosphaerella graminicola (Fuckel) J. Schrott and Pyrenophora tritici-repentis (Died.) Drechsler. Using cluster analysis, we statistically evaluated interrelationships of known factors on the abundance of the fungi on leaf surfaces. Our results showed strongest correlation with Mycosphaerella graminicola and Pyrenophora tritici-repentis abundance to be with lower cultivation intensity and year done by the temperature and the rainfalls. The two pathogens—Puccinia tritici Oerst and Hymenula cerealis Ellis & Everh. occurred only very sparsely in some years and had little positive or negative correlation with named factors. The semi-early and semi-late winter wheat varieties Matchball, Annie, Fakir, and Tobak were used for our experiments. Higher cultivation intensity had protective effect against leaf phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Septoria tritici blotch (STB), caused by the ascomycete fungus Zymoseptoria tritici (formerly known as Mycosphaerella graminicola), is a devastating foliar disease causing major yield losses in wheat each year particularly in North-western Europe. Based on varieties ranked for susceptibility to STB in national trials, it was revealed that Danish Z. tritici populations are very dynamic, both over time and geographical distance. The STB ranking of varieties varied significantly between locations and years indicating differences in virulence between local populations. Comparison of results from seedling tests and field trials reveals that these two types of screenings can be used in combination, since a high correlation was observed in variety rankings for STB susceptibility. Inoculation experiments with seedlings show significant differences in the virulence of pathogen populations originating from different locations within Denmark. Significant changes over time were observed in the variety, Mariboss. An increased susceptibility in this variety followed an intensive cropping period, hence supporting a boom and bust scenario. In conclusion, results from this study indicate the importance of cultivating a diverse set of varieties in order to avoid the boom and bust scenario. Furthermore, varieties should be tested for resistance in several locations in order to ensure an effective and durable resistance. [ABSTRACT FROM AUTHOR]

Plant-growth-promoting rhizobacteria are known as potential biofertilizers and plant-resistance inducers. The current work aims to study the durability of the resistance induced as a response to the inoculation of wheat grains with Paenibacillus sp. strain B2 (PB2) and its influence by plant genotype, growth stage, and Mycosphaerella graminicola strain (the causal agent of Septoria tritici blotch or STB). The results of the plate-counting method showed that PB2 has high potential for wheat-root external colonization [>106 colony-forming unit (CFU)/g of root], and the quantitative real-time polymerase chain reaction (qPCR) analysis demonstrated its internal root-colonization capacity on all tested cultivars. However, the colonization seems to be dependent on wheat-growth stage. The durability of PB2-induced resistance (PB2-IR) was tested at the 3-leaf, tillering, and flag-leaf-growth stages. Additionally, the results showed that the PB2-IR is durable and able to protect the flag leaf, the most important leaf layer during grain fill. It conferred a high protection efficiency (55–94%) against four virulent strains of M. graminicola and over 11 wheat cultivars with different resistance levels to STB. Although, PB2-IR is dependent on M. graminicola strains, wheat genotypes and growth stages, its efficiency, under field conditions, at protecting the last wheat-leaf layers was not an influence. However, it showed 71–79% of protection and reached 81–94% in association with half of the recommended dose of Cherokee® fungicide. This may be explained using laboratory results by its direct impact on M. graminicola strains in these leaf layers and by the indirect reduction of the inoculum coming from leaves infected during the earlier growth stages. Gene expression results showed that PB2-IR is correlated to upregulation of genes involved in defense and cell rescue and a priming effect in the basal defense, jasmonic acid signaling, phenylpropanoids and phytoalexins, and reactive oxygen species gene markers. To conclude, PB2 induces a high and durable resistance against M. graminicola under controlled and field conditions. The PB2-IR is a pathogen strain and is plant-growth-stage and genotype dependent. These results highlight the importance of taking into consideration these factors so as to avoid losing the effectiveness of induced resistance under field conditions. [ABSTRACT FROM AUTHOR]

BACKGROUND Black sigatoka is the main disease of banana crop production and is controlled by using either systemic or contact fungicides through spray applications. Biological efficacy is typically assessed on a whole cropping cycle with a natural infestation and periodic spray applications. Developing a faster methodology for assessment of the biological efficacy of a contact fungicide offers promising perspectives for testing current and new fungicides or application techniques. RESULTS: The methodology is based on the time of occurrence of the first BLSD symptoms. An artificial infestation protocol was optimized by multiplying the infestation spots and by covering the infested plants. Biological efficacy tests were based on a single spray application after infestation combining three mancozeb dose reductions and two nozzle types. Results demonstrated that a 50% reduction in the mancozeb rated dosage gave significant efficacy independently of the nozzle type, with a reduction of the number of lesions of up to 55% compared with control plants. CONCLUSIONS: The described method provides rapid and significant infestation. Further comparison of spray settings and fungicide doses was possible. This methodology will be tested at the plantation scale over a longer period covering the whole crop cycle. © 2018 Society of Chemical Industry Developing a faster methodology to assess the biological efficacy of a contact fungicide offers promising perspectives for testing current and new fungicides or application techniques. [ABSTRACT FROM AUTHOR]

Persimmon (Diospyros kciki) fruit production is severely affected by circular leaf spot worldwide. Mycosphaerella nawae causes circular' leaf spot of persimmon (CLSP) and can result in leaf spot, defoliation, early fruit maturation, and subsequent softening and abscission. The morphology and phylogenetic position of M. nawae within the family Mycosphaerellaceae is, therefore, of utmost importance given its impact on persimmon production. Based on previous morphological and molecular studies, the phylogenetic position of the anamorphic genera associated with M. nawae remain in confusion. In the present study, 15 isolates of M. nawae were collected from the tissue of living leaves exhibiting leaf spot symptoms. A subsample of three isolates was characterized phylogenetically and morphologically. Isolates were compared based on DNA sequence data for the internal transcribed spacer region (ITS 1-5.8S ITS2), part of the 28S nrDNA including domains D1-D3 (LSU), actin (Act), translation elongation factor 1-alpha (EF-la), and RNA polymerase II second largest subunit (rpb2). The anamorph and teleomorph structures, ascospore germination patterns, as well as host specificity were used to describe the isolates. The phylogenetic and morphological analyses revealed that M. nawae requires a new holomorphic genus within Mycosphaerellaceae, described herein as Plurivorosphaerella gen. nov. A host specificity test revealed that Plurivorosphaerella nawae comb. nov. (M. nawae) can superficially colonize, but not infect, apple, peach, cherry, and plum. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate fungal genetic diversity in eight different types of soil in a long-term microplot experiment founded in 1881 in Puławy, Poland. The experiment consists of eight plots (14 m2), each 1 m deep with concrete walls, filled with profiles of different soils. The soils represent the most common Polish soil types (Cambic Leptosol, Fluvic Cambisol, Gleyic Chernozem, Cambisol and Haplic Cambisol, two Brunic Arenosols and Haplic Luvisol). Each soil was characterized by different pH (from 4.0 to 7.5) and organic carbon content (4.5–21.3 g kg-1). The soil structure was not destroyed by compaction because the soils had always been cultivated by hand. The same plant species were always grown in all plots at the same time and the soils received the same fertilization. Moreover, the soils were always under the same weather conditions. Ascomycota was the most abundant phylum in all samples, ranging from 70 to 90% of total fungi. Some genera (Mortierella , Solicoccozyma , and Mycosphaerella) were found to be adapted to a wide range of pH. Acidic soils were dominated by Talaromyces , Cladophialophora , Devriesia , and Saitozyma , while good quality soils primarily consisted of Plectosphaerella , Tetracladium , and Mortierella. The study confirmed previous reports that pH has a decisive influence on soil fungal diversity, but also indicated the strong impact of soil type itself. These studies have launched a new cycle of research in these historical soil profiles. [ABSTRACT FROM AUTHOR]

El banano es uno de los cultivos comestibles más importante en el mundo, sin embargo, es atacado por diferentes patógenos, uno de los más destacados es el hongo Mycosphaerella fijiensis, agente causal de la Sigatoka Negra. Los problemas ambientales y económicos relacionados con los pesticidas usados para su control han estimulado la búsqueda de biomoléculas alternativas no contaminantes. En el grupo de Biotecnología de la Universidad de Antioquia se realizaron estudios previos buscando una alternativa biológica al control de M. fijiensis, en los cuales se determinó la capacidad antifúngica del hongo Ganoderma lucidum como antagonista y posteriormente como fuente de extractos proteicos con actividad inhibitoria in vitro y en plantas de invernadero; estos hallazgos fueron la base de este trabajo, que está enfocado en el estudio de la capacidad enzimática de las proteínas presentes en los extractos proteicos, debido a su capacidad potencial para degradar diferentes compuestos, incluyendo polisacáridos, lípidos, péptidos y ácidos nucleicos, que constituyen partes esenciales de una célula viva; por lo tanto, estos extractos pueden actuar como posibles agentes antifúngicos. En este estudio, los extractos proteicos de G. lucidum obtenidos a partir de cultivos en biorreactor (BIOFLO 110®) fueron caracterizados en términos de sus actividades enzimáticas: deoxyribonucleasa, ribonucleasa, proteasa, glucanasa y quitinasa. Los extractos también fueron fraccionados y cada fracción obtenida fue evaluada para la capacidad inhibitoria contra el hongo fitopatógeno M. fijiensis, y a través de los análisis de espectrometría de masas se confirmó la presencia de diferentes enzimas con potencial antifúngico. [ABSTRACT FROM AUTHOR]