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Deadwood represents a dynamic carbon pool in forest ecosystems where microbial decomposition causes fluxes of CO2 to the atmosphere through respiration and organic carbon to the soil through leakage and fragmentation. This study characterises different stages of deadwood of Norway spruce (Picea abies). 35 Norway spruce trees were sampled and categorized on a 0–5 decay scale. For the 14 trees in classes 0–3, two stem discs were collected from two heights. For the 21 trees in classes 4 and 5, a single sample per tree was taken, because decay was relatively uniform throughout the stem. The relative amount of hemicellulose and cellulose declined moderately from decay class 1 to 3 and substantially from decay class 3 to class 4 but small amounts were still present in decay class 5. The relative lignin proportion increased substantially from decay class 3 to 4 and dominated in decay class 5. Relative carbon content increased from 50 to 56% during the decomposition process due to the increasing accumulation of lignin residuals being a typical signature of brown rot decay. A laboratory experiment including three species of brown rot fungi verified decomposition close to 70% of Norway spruce biomass and resulted in 55% carbon content. This was similar to the carbon content in decay class 4 and 5. A novel approach is presented to quantify the carbon flux from deadwood to the soil. First, we calculated the residual proportion of carbon in decayed wood compared to the initial carbon content of live trees. Subsequently, we extended the calculation to determine the amount of remaining carbon from non-decayed wood that was transferred to the soil during each decay class. The approach showed that Norway spruce wood decomposition under field conditions transfers at least 39–47% of the initial wood carbon to the soil carbon pool, depending on soil type. This strengthens the previously under-communicated fact that the carbon flux from deadwood to soil is higher from brown rot decomposition in boreal forests than the corresponding carbon flux in temperate and tropical forests where deadwood is more influenced by white rot fungi. [ABSTRACT FROM AUTHOR]

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A novel species of Mucor was identified as the causal agent of a brown rot of Prunus domestica (European plum), widely grown in the south of Xinjiang, China. This disease first appears as red spots after the onset of the fruits. With favorable environmental conditions, fruit with infected spots turn brown, sag, expand, wrinkle, and harden, resulting in fruit falling. Fungal species were isolated from infected fruits. A phylogenetic analysis based on internal transcribed spacer (ITS) regions and the large subunit (LSU) of the nuclear ribosomal RNA (rRNA) gene regions strongly supported that these isolates made a distinct evolutionary lineage in Mucor (Mucoromycetes, Mucoraceae) that represents a new taxonomic species, herein named as Mucor xinjiangensis. Microscopic characters confirmed that these strains were morphologically distinct from known Mucor species. The pathogenicity of M. xinjiangensis was confirmed by attaching an agar disk containing mycelium on fruits and re-isolation of the pathogen from symptomatic tissues. Later, fourteen fungicides were selected to determine the inhibitory effect on the pathogen. Further, results showed that difenoconazole had the best effect on the pathogen and the strongest toxicity with the smallest half maximal effective concentration (EC50) value, followed by a compound fungicide composed of difenoconazole with azoxystrobin, mancozeb, prochloraz with iprodione, pyraclostrobin with tebuconazole, and trifloxystrobin with tebuconazole and ethhylicin. Present study provides the basis for the prevention and control of the novel plum disease and its pathogen. [ABSTRACT FROM AUTHOR]

Fungal traits can provide a mechanistic understanding of how wood‐inhabiting fungi interact with their environment and how that influences community assembly in deadwood. However, fungal trait exploration is relatively new and almost no studies measure fungal traits in their environment.In this study we tested species‐ and trait‐environment relationships in reproducing fungal communities inhabiting 571 Norway spruce (Picea abies) logs in 55 isolated forest patches (0.1–9.9 ha) of different naturalness types, located in Northern boreal Sweden. The studied patches were (1) semi‐natural set‐aside patches within highly managed landscapes, or (2) old‐growth natural patches located in an unmanaged landscape. We tested species and trait relationships to deadwood substrate and forest patch variables. We measured mean fruit body size and density for each of the 19 species within communities.Traits assembled in relation to log decay stage and forest patch naturalness, illustrating the important role of deterministic environmental filtering in shaping reproducing wood‐inhabiting fungal communities. Early decay stage communities had larger, less dense, annual fruiting bodies of half‐resupinate type and were more often white‐rot fungi. Species rich mid‐decay stage communities had mixed trait assemblages with more long lived perennial fruit bodies of intermediate size, and both brown‐ and white‐rot fungi equally represented. Finally, late decay stage communities had smaller, denser and perennial fruit bodies, more often of the brown‐rot type.The relationships between the studied traits and decay stages were similar in both set‐aside and natural patches. However, set‐aside semi‐natural patches in highly managed landscapes more frequently supported species with smaller, perennial and resupinate fruit bodies compared to natural patches in an unmanaged landscape.Synthesis. We found that log decay stage was the primary driver of fungal community assembly of species and traits in isolated forest patches. Our results suggest that decay stage filters four reproduction traits (fruit body density, size, lifespan and type) and one resource‐use trait (white or brown rot). Our results highlights, for the first time, that communities with diverse fungal reproductive traits are maintained foremost across all deadwood decay stages under different forest naturalness conditions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Simple Summary: The tubers of Gastrodia elata, used in traditional medicine for over two thousand years, are highly susceptible to fungal infections, making tuber rot a common issue during its cultivation. This study investigated a significant outbreak of brown rot disease affecting G. elata f. elata in Hunan Province, China. Typical symptoms include initial brown spots on the tuber surface that expand and darken, with the spots spreading inward and causing the surrounding tissue to transition from brown to black. In this study, the fungal pathogen causing brown rot disease on G. elata was isolated and examined in detail for morphological characteristics, including color, sporulation structures, and spore size. Its identification was further supported by phylogenetic analysis. The findings indicated that the fungal pathogen causing brown rot disease on G. elata f. elata was Clonostachys rosea. Gastrodia elata, commonly known as Tian Ma, is a perennial mycoheterotrophic orchid. Qianyang Tian Ma (QTM), a geographical indication agricultural product from Hongjiang City, Hunan Province, China, is primarily characterized by the red variety, G. elata f. elata. A severe outbreak of tuber brown rot disease was documented in QTM during the harvesting season in Hunan. The fungal pathogen associated with the disease was isolated on potato saccharose agar (PSA) and identified through morphological and phylogenetic analyses. Pathogenicity tests were performed on healthy tubers of G. elata f. elata. The results showed that the representative isolate, named TMB, produced white hyphal colonies with a ring structure, broom-like phialides, partially curved ellipsoidal conidia, and orange–yellow spherical ascocarps on PSA. Phylogenetic analysis of the ITS, LSU, rpb2 and tub2 sequences using Bayesian and maximum-likelihood methods identified the isolate TMB as Clonostachys rosea, based on morphological and phylogenetic data. Pathogenicity tests revealed typical disease symptoms on healthy G. elata tubers 15 days post-inoculation with the isolate TMB. C. rosea is known to cause diseases in economically important crops, but there are no reports of its occurrence on G. elata f. elata in China. This study provides valuable insights into the occurrence, prevention, and control of brown rot disease in G. elata f. elata. [ABSTRACT FROM AUTHOR]

BACKGROUND: Peach brown rot, caused by the pathogen Monilinia fructicola, represents a significant postharvest infectious disease affecting peach fruit. This disease is responsible for a substantial increase in fruit decay rates, leading to significant economic losses, often exceeding 50%. Currently, there is a growing interest in identifying biocontrol agents to mitigate peach brown rot, with a predominant interest in Bacillus species. RESULTS: In this investigation, we isolated 410 isolates of actinomycetes from non‐farmland ecosystem soil samples. Subsequently, 27 isolates exhibiting superior inhibitory capabilities were selected. Among these, strain XDS1‐5 demonstrated the most robust fungistatic effect against brown rot disease, achieving an 80% inhibition rate in vitro and a 66% inhibition rate in vivo. XDS1‐5 was identified as belonging to the Streptomyces virginiae species. Furthermore, a fermentation filtrate of XDS1‐5 exhibited the ability to metabolize 34.21% of the tested carbon sources and 7.37% of the tested nitrogen sources. Particularly noteworthy was its capacity to disrupt the cell membrane structure directly, leading to increased cell membrane permeability and cytoplasmic leakage. Additionally, our investigation indicated that indoline, a metabolite produced by XDS1‐5, played a pivotal role in inhibiting the growth of M. fructicola. CONCLUSION: In summary, our study has identified a biocontrol actinomycete, XDS1‐5, with the potential to effectively inhibit postharvest brown rot disease in peaches. This finding holds great significance for the biological control of peach brown rot, offering promising prospects for mitigating the economic losses associated with this devastating disease. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Brown-rot fungi are large fungi that can decompose the cell walls of wood; they are notable for their secretion of diverse and complex enzymes that synergistically hydrolyze natural wood cellulose molecules. Fomitopsis pinicola (F. pinicola) is a brown-rot fungus of interest for its ability to break down the cellulose in wood efficiently. In this study, through a combination of rDNA-ITS analysis and morphological observation, the wood decay pathogen infecting Korean pine (Pinus koraiensis Siebold and Zucc.) was identified. Endoglucanase (CMCase) and β-glucosidase were quantified using the DNS (3,5-Dinitrosalicylic acid) method, and the cellulase activity was optimized using a single-factor method and orthogonal test. The results revealed that the wood-decaying fungus NE1 identified was Fomitopsis pinicola with the ITS accession number OQ880566.1. The highest cellulase activity of the strain reached 116.94 U/mL under the condition of an initial pH of 6.0, lactose 15 g·L−1, KH2PO4 0.5 g·L−1, NH4NO3 15 g·L−1, MgSO4 0.5 g·L−1, VB1 0.4 g·L−1, inoculated two 5 mm fungal cakes in 80 mL medium volume cultured 28 °C for 5 days. This laid a foundation for improving the degradation rate of cellulose and biotransformation research, as well as exploring the degradation of cellulose by brown rot fungi. [ABSTRACT FROM AUTHOR]

Introduction: Brown rot is the most important fungal disease affecting stone fruit and it is mainly caused by Monilinia fructicola, M. laxa and M. fructigena. Monilinia spp. are necrotrophic plant pathogens with the ability to induce plant cell death by the secretion of different phytotoxic molecules, including proteins or metabolites that are collectively referred to as necrotrophic effectors (NEs). Methods: We exploited the genomes of M. fructicola, M. laxa and M. fructigena to identify their common group of secreted effector proteins and tested the ability of a selected set of effectors to induce cell death in Nicotiana benthamiana, Solanum lycopersicum and Prunus spp. leaves. Results: Fourteen candidate effector genes of M. fructicola, which displayed high expression during infection, were transiently expressed in plants by agroinfiltration using a modified Tobacco Rattle Virus (TRV)-based expression system. Some, but not all, effectors triggered leaf discoloration or cell death in N. benthamiana and S. lycopersicum, which are non-hosts for Monilinia and in Prunus spp., which are the natural hosts. The effector MFRU_030g00190 induced cell death in almost all Prunus genotypes tested, but not in the Solanaceous plants, while MFRU_014g02060, which is an ortholog to BcNep1, caused necrosis in all plant species tested. Conclusion: This method provides opportunities for screening Prunus germplasm with Monilinia effector proteins, to serve as a tool for identifying genetic loci that confer susceptibility to brown rot disease. [ABSTRACT FROM AUTHOR]

Chestnut production is considered one of the most important economic resources of rural mountainous areas in Greece. Lately, producers report a steep rise in the incidence of brown rot disease caused by the fungus Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales), which results in severe chestnut rot. The pathogen is considered an emerging pathogen in many countries worldwide (Italy, France, Switzerland, Australia, New Zealand). This study aimed at (a) exploring the incidence of the brown rot disease in Vria (Regional Unit of Pieria, Region of Central Makedonia, Greece), (b) isolating and identifying the causal agent of the disease, (c) exploring the fungus presence at different phenological stages of the chestnut trees, and (d) implementing species-specific Bar- High Resolution Melting Analysis (HRM) for the early detection of G. smithogilvyi in chestnuts. G. smithogilvyi occurrence in chestnut tissues was more severe in June (59 %), nearly disappeared in July (19 %) and August (7 %) and increased again during harvesting time in September (57 %). This result could be attributed to a sum of different factors, including climate conditions. Moreover, it was demonstrated that G. smithogilvyi can be identified using a Bar-HRM analysis of chestnut tissues (buds, flowers and nuts). Results of this study clearly demonstrate that Bar-HRM can be used for the accurate, rapid and reliable identification of G. smithogilvyi universally on infected samples from different localities. [ABSTRACT FROM AUTHOR]

Transparent wood composite (TWC) is a novel wood-based polymer composite that combines high optical transmittance (more than 80%) with good mechanical and thermal properties. It offers numerous potential areas of applications, including smart windows, energy-efficient elements, display panels, light diffusers and substrates for solar cells. The sensitivity of TWC towards moisture and biological agents such as fungus becomes important for certain applications. In this study, TWCs were prepared using wood veneers of Populus deltoides (poplar) and Melia dubia (melia) through the process of lignin-modification bleaching and epoxy-resin infiltration. Water-absorption studies were carried out by immersing TWC specimens in deionized water for a duration of 400 h and by exposing specimens to different relative humidity (RH) conditions. The fungal resistance was evaluated by exposing specimens to a brown rot (Oligoporous placentus) and a white rot (Trametes hirsutu) fungus. Results indicated that TWC can absorb a maximum of 8% to 10% of water during a water immersion test for a period of 400 h. Exposing TWC specimens to different RH conditions resulted in no significant moisture adsorption. TWC was highly resistant to white rot and brown rot fungus. [ABSTRACT FROM AUTHOR]

In this study we separated the chemical components of cork from Quercus variabilis by various solvent extraction and alcoholysis methods. We identified the content and chemical composition of suberin and dichloromethane extract with gas chromatography-mass spectrometry (GC-MS) and analyzed the antifungal effects of different cork extracts against wood-decaying fungi. The results showed that the main structural component of cork, suberin, averaging 36.34% of the total dry weight, exhibited a pronounced inhibitory effect on wood-decaying fungi, compared to the dichloromethane extract. By the end of the entire culture period, the colony diameter of white rot fungi was 5 mm in the 40 mg/mL suberin treatment group, 19 mm for brown rot fungi, both significantly smaller than the control group (90 mm). Hydroxy fatty acids, free fatty acids, and α,ω-diacids may be the key components contributing to the antifungal activity of suberin. The inhibitory mechanism of suberin components on wood-decaying fungi may involve suppressing the respiratory metabolism of the fungi and increasing the permeability of their cell membranes, thereby limiting their normal life activities. [ABSTRACT FROM AUTHOR]

BACKGROUND: Peach brown rot caused by Monilinia fructicola severely affects the quality and yield of peach, resulting in large economic losses worldwide. Methyl benzimidazole carbamate (MBC) fungicides and sterol demethylation inhibitor (DMI) fungicides are among the most applied chemical classes used to control the disease but resistance in the target pathogen has made them risky choices. Timely monitoring of resistance to these fungicides in orchards could prevent control failure in practice. RESULTS: In the current study, we developed methods based on recombinase polymerase amplification (RPA) and CRISPR/Cas12a systems to detect MBC and DMI resistance based on the E198A mutation in the β‐tubulin (MfTub2) gene and the presence of the Mona element in the upstream region of the MfCYP51, respectively. For MBC resistance, RPA primers were designed that artificially incorporated PAM sites to facilitate the CRISPR/Cas12a reaction. Subsequently, specific tcrRNAs were designed based on the E198A mutation site. For the detection of the Mona element, we designed RPA primers M‐DMI‐F2/M‐DMI‐R1 that in combination with crRNA1 detected 'Mona' and distinguished resistant from sensitive strains. CONCLUSION: Both methods exhibited high sensitivity and specificity, requiring only a simple isothermal device to obtain results within 1 h at 37 °C. The FQ‐reporter enabled visualization with a handheld UV or white light flashlight. This method was successfully used with purified DNA from lab cultures and crude DNA from symptomatic fruit tissue, highlighting its potential for on‐site detection of resistant strains in orchards. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background. European plum (Prunus domestica L.) is a widespread stone fruit crop in Krasnodar Territory and Adygea. Development of fungal diseases, including brown rot, shot hole, red leaf spot, and rust, leads to a significant decrease in the harvest and marketable quality of P. domestica fruits. Therefore, breeding for resistance to these diseases is very important for planting highly productive European plum orchards. The objective of this study was to identify P. domestica cultivars resistant to four fungal diseases under the conditions of the foothill zone of Adygea. Materials and methods. The research material included 25 P. domestica cultivars from the collection orchard of Maikop Experiment Station of VIR. Resistance to fungal diseases was assessed in 2011–2022 using a conventional scale. Results and conclusions. Weather and climate conditions during the flowering, fruit growth and ripening periods of European plum affected the degree of damage inflicted by fungal diseases. Many years of testing resulted in identifying P. domestica cultivars with different scores of resistance to brown rot, shot hole, and rust. Ten P. domestica cultivars were characterized by group resistance to the abovementioned diseases: ‘Anna Shpet’ (k-3325), ‘Vengerka Rannyaya’ (k-3459), ‘Vengerka Italyanskaya’ (k-3444), ‘Musa Dzhaliev’ (k-26994), ‘Vengerka Vkusnaya’ (k-43323), ‘Persikovaya Michurina’ (k-30706), ‘Chernosliv Adygeyskiy’ (k-23743), ‘Chernosliv Shuntukskiy’ (k-23707), ‘Yekaterina’ (yellow) (k-3520), and ‘Vasсova’ (k-27639). They can be recommended to plum breeders for the development of P. domestica cultivars with group resistance to fungal diseases in the foothill zone of Adygea.

Peach brown rot, attributed to Monilinia fructicola, presents a significant threat to postharvest peach cultivation, causing losses of up to 80%. With an increasing number of countries, spearheaded by the European Union, imposing bans on chemical agents in fruit production, there is a growing interest in mining highly active antibacterial compounds from biological control strains for postharvest disease management. In this study, we highlight the unique ability of Streptomyces lincolnensis strain JCP1‐7 to inhibit M. fructicola sporulation, despite its limited antimicrobial efficacy. Through GC–MS analysis, eucalyptol was identified as the key compound. Fumigation of diseased fruits with eucalyptol at a concentration of 0.0335 μg cm−3 demonstrated an in vivo inhibition rate against M. fructicola of 93.13%, completely suppressing spore formation. Transcriptome analysis revealed the impact of eucalyptol on multiple pathogenesis‐related pathways, particularly through the inhibition of catalase 2 (Cat2) expression. Experiments with a MfCat2 knockout strain (ΔMfCat2) showed reduced pathogenicity and sensitivity to JCP1‐7 and eucalyptol, suggesting MfCat2 as a potential target of JCP1‐7 and eucalyptol against M. fructicola. Our findings elucidate that eucalyptol produced by S. lincolnensis JCP1‐7 inhibits M. fructicola sporulation by regulating MfCat2, thereby effectively reducing postharvest peach brown rot occurrence. The use of fumigation of eucalyptol offers insights into peach brown rot management on a large scale, thus making a significant contribution to agricultural research. [ABSTRACT FROM AUTHOR]

Within a few years of the establishment of the convict settlement at Sydney Cove, the potato became one of the staple crops of the population due to its relatively high yield and the prior experience of the convicts and free settlers with growing the crop. In 1894, Henry Tryon described a new disease in southern Queensland that caused rapid wilting of plants, a ring of slightly translucent tissue just below the surface of affected tubers, oozing of a thick, white fluid from the 'eyes', and ultimately rotting of the tubers. It soon became known as 'Tryon's disease'. He found that a microbe (bacterium) was always associated with affected tubers and stems, provided a very brief description of the bacterial cells and named the microbe Bacillus vascularum solani. A few years later the American scientist Erwin Frink Smith wrote a paper on a new disease (brown rot) of solanaceous plants including the potato and tomato, in which he called the causal agent Pseudomonas solanacearum , now known as Ralstonia solanacearum. Smith dismissed Tryon's prior claim to the discovery of the disease with some of his comments being personal and scathing. Tryon had the last word, however, cloaking his response in restrained and somewhat convoluted tones. In 1894, the Queensland government entomologist, and later vegetable pathologist, Henry Tryon (1856–1943) discovered a new disease that caused potato tubers to become rotted and putrid. He consistently found bacterial cells in a thick mucilaginous gum in the vascular tissues of wilted stems and infected tubers, and gave it the name Bacillus vascularum solani. The American bacteriologist Erwin Frink Smith would not accept Tryon's discovery, instead naming the causal agent Pseudomonas solanacearum. That bacterium, now called Ralstonia solanacearum is a significant plant pathogen worldwide. Photograph by an unknown person. [ABSTRACT FROM AUTHOR]

Brown lesions observed on ginger rhizomes in Kochi Prefecture, Japan, appeared to be symptoms of a previously unknown disease. A filamentous fungus was isolated at high frequency from the lesions and identified as Musidium stromaticum based on its morphology and molecular analyses of ITS, LSU, TEF1-α, and RPB2. Rhizomes developed the same symptoms after inoculation with the fungus. We propose the name "brown rhizome rot" to describe this new disease of ginger. This study is the first report of M. stromaticum as a plant pathogen of ginger. [ABSTRACT FROM AUTHOR]

In 2020 and 2021, peach fruit with natural disease and decay were collected from orchards in Zhejiang Province. Then the fungal pathogens were isolated from the diseased spots and identified by morphological characteristics, molecular biological identification (rDNA-ITS sequence analysis) and pathogenicity detection. The antifungal effect of cinnamon essential oil on the fungal pathogens in vitro and in vivo were also investigated. The results showed that two fungal pathogens with strong pathogenicity were isolated, and identified as Monilinia fructicola and Rhizopus stolonifer, which caused brown rot and soft rot, respectively. Cinnamon essential oil inhibited the growth of M. fructicola and R. stolonifer, and the minimum inhibitory concentrations were 0.4 and 0.8 mL/L, respectively. M. fructicola was more sensitive to cinnamon essential oil. Cinnamon essential oil fumigation could reduce the disease incidence and lesion diameter of brown rot and soft rot of peach fruit caused by these two fungal pathogens. Therefore, cinnamon essential oil could be used as a natural fungicide to control fungal diseases of peach fruit. [ABSTRACT FROM AUTHOR]

In the world, Ralstonia solanacearum, the second most harmful bacterial phytopathogen, poses a serious danger to potato crop by causing brown rot disease, which can result in losses of up to 100%. For that, this study aims to isolate and identify of pathogenic bacteria causing brown rot disease and biocontrol it using ZnONPs synthesized by fungal strain. Eighteen infected potato cv. Cara samples were collected from different six regions of El-Minya governorate, Egypt. Isolation, identification, and pathogenicity tests were done for the most common pathogenic bacteria. Also, 18 native agricultural soil samples from 6 regions of El-Minya governorate, Egypt. Additionally, isolation and identification of the most common fungal isolate can synthesize ZnONPs. Mycosynthesized ZnONPs were characterized by UV, TEM, SEM, EDX, XRD, FTIR, Zeta potential, and particle size. Cytotoxicity test for mycosynthesized ZnONPs was done to determine the safety level of obtained nanoparticles which its dominant spherical or hexagonal shapes and small in size at 42.2 ± 3.0 nm. Results showed that the pathogenic bacterial isolate was identified using morphological, biochemical, and molecular as Ralstonia solanacearum (OR533702). Also, 16 fungal isolates were isolated and the most common was selected and identified as Epicoccum nigrum (OR533699) using microscopic, macroscopic, and molecular identification. Additionally, the result showed the selected fungal strain E. nigrum has high efficacy with inhibition zone diameter (2.20 ± 0.20) mm at 100 μg/ mL (5mM) against R. solanacearum. This study concluded that mycosynthesized ZnONPs have a potent effect against R.solanacearum compared to Revanol 50% as a traditional product. [ABSTRACT FROM AUTHOR]

Saffron corm rot is caused by the bacterium Burkholderia gladioli pv. gladioli (Bgg) is an important disease affecting saffron cultivation. This study aimed to evaluate the effect of different doses of sodium bicarbonate and three copper-based compounds (copper oxychloride, Bordeaux and Nordox) on the population of Bgg isolates in vitro. Additionally, the sensitivity of the Bgg isolates to 21 antibiotics was investigated. Two weeks after inoculation, the disease symptoms appeared as dry rot and brown lesions around the inoculated area. Varying degrees of virulence were observed among the Bgg isolates, with the Bg16 inducing the most severe symptoms. The minimum inhibitory concentrations (MICs) were determined as copper oxychloride 3.5/1000, Bordeaux and sodium bicarbonate 12%, and Nordox 1.5/1000. The Bgg isolates were sensitive to nine antibiotics. The largest inhibitory zone diameters were observed around trimethoprim-sulfamethoxazole, nalidixic acid, gentamicin, and amikacin discs. One week after cultivation, the copper compounds decreased the bacterial population compared to the control, but no significant difference was observed between them in the second week. The most effective treatments in reducing the Bgg population were copper oxychloride at 2/1000 and 3/1000, Bordeaux at 8% and 10%, and Nordox at 1/1000 and 1.5/1000. The efficacy of the identified effective treatments will be further evaluated under field conditions. [ABSTRACT FROM AUTHOR]

Wood decay fungi alter the abiotic and biotic properties of deadwood, which are important as nurse logs for seedling regeneration. However, the relationship between fungal decay type and seedling performance has not been evaluated experimentally. In this study, we examined the germination, growth, and survival of six arbuscular mycorrhizal (AM) and six ectomycorrhizal (ECM) tree species on three substrates (pine logs with brown and white rot and soil) by conducting seed‐sowing experiments in a mixed forest dominated by Pinus densiflora and Quercus serrata. Analysis using ribosomal DNA internal transcribed spacer 1 (rDNA ITS1) sequencing revealed that the fungal community was significantly different across three substrates. The richness of operational taxonomic units (OTUs) of AM and ECM fungi was the largest on brown rot logs and soil, respectively. The substrate significantly affected the seedling performance when comparing wood decay types, but these were not consistent across the mycorrhizal status of the seedlings. Nevertheless, seedlings of some AM trees showed better growth and enhanced mycorrhizal colonization on brown rot logs than on white rot logs. The wood decay type influenced fungal communities in the logs and the performance of some seedling species partly by different mycorrhizal colonization rates. However, the effect was seedling species dependent and showed no apparent difference between AM and ECM trees. [ABSTRACT FROM AUTHOR]

Summary: Unlike 'white rot' (WR) wood‐decomposing fungi that remove lignin to access cellulosic sugars, 'brown rot' (BR) fungi selectively extract sugars and leave lignin behind. The relative frequency and distribution of these fungal types (decay modes) have not been thoroughly assessed at a global scale; thus, the fate of one‐third of Earth's aboveground carbon, wood lignin, remains unclear.Using c. 1.5 million fungal sporocarp and c. 30 million tree records from publicly accessible databases, we mapped and compared decay mode and tree type (conifer vs angiosperm) distributions. Additionally, we mined fungal record metadata to assess substrate specificity per decay mode.The global average for BR fungi proportion (BR/(BR + WR records)) was 13% and geographic variation was positively correlated (R2 = 0.45) with conifer trees proportion (conifer/(conifer + angiosperm records)). Most BR species (61%) were conifer, rather than angiosperm (22%), specialists. The reverse was true for WR (conifer: 19%; angiosperm: 62%). Global BR proportion patterns were predicted with greater accuracy using the relative distributions of individual tree species (R2 = 0.82), rather than tree type.Fungal decay mode distributions can be explained by tree type and, more importantly, tree species distributions, which our data suggest is due to strong substrate specificities. [ABSTRACT FROM AUTHOR]

Leaf chlorosis and root browning with root rot were observed on mature Cinnamomum camphora (Linn) Presl between 2021 and 2023 in Hangzhou, Zhejiang province, China. Three strains of fungi consistently isolated from the diseased roots were selected for identification and pathogenicity test. They were identified as Fusarium decemcellulare Brick based on the morphology and phylogenetic analysis using combined sequence data. The pathogenicity of the strains was verified by inoculating on C. camphora seedings in pots. Fusarium decemcellulare was reisolated from the artificially inoculated roots of C. camphora seedings. To our knowledge, this is the first report that F. decemcellulare causes root rot on C. camphora worldwide and its potential threat should be monitored. [ABSTRACT FROM AUTHOR]

Annual spray diaries from orchardists in the two main stonefruit growing regions, Central Otago and Hawke's Bay, were analysed. The analysis was restricted to products for disease and arthropod pest control. It included apricots, cherries, nectarines, peaches and plums grown as fresh fruit for export and domestic markets, and processing crops. Mean fungicide and bactericide applications declined from 13 to 9/block/year in Central Otago, but rose from 11 to 13 sprays in Hawke's Bay. Central Otago is drier than Hawke's Bay and the regional spray programmes now better match the respective climates. Despite large annual variations in rainfall and numbers of brown rot (Monilinia fructicola) infection periods in both regions, there was little correlation with the numbers of fungicides applied that had activity against brown rot. The products used against diseases changed substantially during the study period. Insecticide and miticide sprays averaged 5 applications per year in Central Otago at the start of the study and declined to 4-6/crop/year (overall mean of 4) by 2018–19. Hawke's Bay growers used 1–3 insecticide sprays per crop (overall mean of 2) throughout the study. The proportion of selective insecticides applied grew in Central Otago, but fell in Hawke's Bay. [ABSTRACT FROM AUTHOR]

Dowel bearing strength of three cross-laminated timber (CLT) species (Douglas-fir, Norway spruce, spruce pine fir) were periodically assessed through 40 weeks of exposure to two brown rot fungi species (Gloeophyllum trabeum and Rhodonia placenta). Time-dependent regression models were developed to describe the relationship between level of fungal exposure and dowel bearing strength of CLT. Obtained dowel bearing strength values were used to predict the capacity of floor-to-wall CLT connection systems. Predicted strength values were compared with capacity of actual connection systems which were subjected to similar biodeterioration treatments. Significant reductions in the dowel bearing strength of CLT were observed 30 weeks after fungal inoculation. Similar patterns of degradation were observed for both fungi in all three CLT species, but R. placenta was slightly more aggressive than G. trabeum, causing a 16.2 MPa reduction in dowel bearing strength of Douglas-fir after 40 weeks of exposure. Connection capacities estimated using National Design Specification yield models for dowel type fasteners and the dowel bearing strength of fungal-damaged CLT were consistent with observed properties and were within 85% of actual capacity of connections tested, especially in early stages of decay. [ABSTRACT FROM AUTHOR]

Tomatoes possess significant nutritional and economic value. However, frequent diseases can detrimentally impact their quality and yield. Images of tomato diseases captured amidst intricate backgrounds are susceptible to environmental disturbances, presenting challenges in achieving precise detection and identification outcomes. This study focuses on tomato disease images within intricate settings, particularly emphasizing four prevalent diseases (late blight, gray leaf spot, brown rot, and leaf mold), alongside healthy tomatoes. It addresses challenges such as excessive interference, imprecise lesion localization for small targets, and heightened false-positive and false-negative rates in real-world tomato cultivation settings. To address these challenges, we introduce a novel method for tomato disease detection named TomatoDet. Initially, we devise a feature extraction module integrating Swin-DDETR's self-attention mechanism to craft a backbone feature extraction network, enhancing the model's capacity to capture details regarding small target diseases through self-attention. Subsequently, we incorporate the dynamic activation function Meta-ACON within the backbone network to further amplify the network's ability to depict disease-related features. Finally, we propose an enhanced bidirectional weighted feature pyramid network (IBiFPN) for merging multi-scale features and feeding the feature maps extracted by the backbone network into the multi-scale feature fusion module. This enhancement elevates detection accuracy and effectively mitigates false positives and false negatives arising from overlapping and occluded disease targets within intricate backgrounds. Our approach demonstrates remarkable efficacy, achieving a mean Average Precision (mAP) of 92.3% on a curated dataset, marking an 8.7% point improvement over the baseline method. Additionally, it attains a detection speed of 46.6 frames per second (FPS), adeptly meeting the demands of agricultural scenarios. [ABSTRACT FROM AUTHOR]

Nectarines can be affected by many diseases, resulting in significant production losses. Natural products, such as essential oils (EOs), are promising alternatives to pesticides to control storage rots. This work aimed to test the efficacy of biofumigation with EOs in the control of nectarine postharvest diseases while also evaluating the effect on the quality parameters (firmness, total soluble solids, and titratable acidity) and on the fruit fungal microbiome. Basil, fennel, lemon, oregano, and thyme EOs were first tested in vitro at 0.1, 0.5, and 1.0% concentrations to evaluate their inhibition activity against Monilinia fructicola. Subsequently, an in vivo screening trial was performed by treating nectarines inoculated with M. fructicola, with the five EOs at 2.0% concentration by biofumigation, performed using slow-release diffusers placed inside the storage cabinets. Fennel, lemon, and basil EOs were the most effective after storage and were selected to be tested in efficacy trials using naturally infected nectarines. After 28 days of storage, all treatments showed a significant rot reduction compared to the untreated control. Additionally, no evident phytotoxic effects were observed on the treated fruits. EO vapors did not affect the overall quality of the fruits but showed a positive effect in reducing firmness loss. Metabarcoding analysis showed a significant impact of tissue, treatment, and sampling time on the fruit microbiome composition. Treatments were able to reduce the abundance of Monilinia spp., but basil EO favored a significant increase in Penicillium spp. Moreover, the abundance of other fungal genera was found to be modified. [ABSTRACT FROM AUTHOR]

Saprotrophic fungi that cause brown rot of woody biomass evolved a distinctive mechanism that relies on reactive oxygen species (ROS) to kick-start lignocellulosic polymers' deconstruction. These ROS agents are generated at incipient decay stages through a series of redox relays that shuttle electrons from fungus's central metabolism to extracellular Fenton chemistry. A list of genes has been suggested encoding the enzyme catalysts of the redox processes involved in ROS's function. However, navigating the functions of the encoded enzymes has been challenging due to the lack of a rapid method for protein synthesis. Here, we employed cell-free expression system to synthesize four redox or degradative enzymes, which were identified, by transcriptomic data, as conserved players of the ROS oxidation phase across brown rot fungal species. All four enzymes were successfully expressed and showed activities that enable confident assignment of function, namely, benzoquinone reductase (BQR), ferric reductase, a-L-arabinofuranosidase (ABF), and heme-thiolate peroxidase (HTP). Detailed analysis of their catalytic features within the context of brown rot environments allowed us to interpret their roles during ROS-driven wood decomposition. Specifically, we validated the functions of BQR as the driver redox enzyme of Fenton cycles and reconstructed its interactions with the co-occurring HTP or laccase and ABF. Taken together, this research demonstrated that the cell-free expression platform is adequate for synthesizing functional fungal enzymes and provided an alternative route for the rapid characterization of fungal proteins, escalating our understanding of the distinctive biocatalyst system for plant biomass conversion. [ABSTRACT FROM AUTHOR]

Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales) is the main causal agent of chestnut brown rot on sweet chestnut worldwide. The rotting of nuts leads to alterations in the organoleptic qualities and decreased fruit production, resulting in significant economic losses. In 2021, there was an important outbreak of chestnut rot in southern Galicia (Spanish northwest). The profile of secondary metabolites from G. smithogilvyi was studied, especially to determine its capability for producing mycotoxins, as happens with other rotting fungi, due to the possible consequences on the safety of chestnut consumption. Secondary metabolites produced by isolates of G. smithogilvyi growing in potato dextrose agar (PDA) medium were identified using liquid chromatography coupled with high-resolution mass spectrometry. Three metabolites with interesting pharmacological and phyto-toxicological properties were identified based on their exact mass and fragmentation patterns, namely adenosine, oxasetin, and phytosphingosine. The capacity of G. smithogilvyi to produce adenosine in PDA cultures was assessed, finding concentrations ranging from 176 to 834 µg/kg. Similarly, the production of mycotoxins was ruled out, indicating that the consumption of chestnuts with necrotic lesions does not pose a health risk to the consumer in terms of mycotoxins. [ABSTRACT FROM AUTHOR]

The response of plum cultivars and forms of Prunus domestica L. to early (Monilniia laxa) and late brown rot (Monilinia fructigena) was monitored over the period 2021-2023. The experiment was carried out in a collection plantation of the Experimental Station – Dryanovo, a unit of RIMSA –Troyan. Observations were made on the local varieties (forms) Kleshtachka, Pestilka, Bambulka and Dupla, and the selected varieties Gabrovska and Strinava. Variety Stanley was selected as the control. Climatic conditions influence the development and degree of attack by phytopathogens in different varieties. During the study period, the highest amount of precipitation was recorded in 2023 – 1010 mm, compared to the average amount for a twenty-year period for the area of Dryanovo (745.3 mm). This provokes a strong attack of both brown rot species. In the case of the variety Stanley, the degree of attack by M. laxa was 68.8%. In relation to early brown rot, the local varieties and the variety Strinava have less than 12.40% attack rate. In the case of variety Gabrovska, 5.20% were recorded. The response of local varieties to late brown rot ranged from 18.00% (Bambulka) to 28.40% (Pestilka). The varieties Gabrovska, Strynava and Stanley had less than 8.50% attack rate. The local varieties (forms) and the Gabrovska variety are defined as poorly susceptible to early brown rot. The variety Strinava is medium sensitive and the variety Stanley is sensitive. Kleshtachka and Pestilka are moderately susceptible to late brown rot and Dupla and Bambulka are slightly susceptible. The cultivars Gabrovska and Strinava are slightly susceptible to late brown rot. [ABSTRACT FROM AUTHOR]

Biological durability remains an understudied area of mass timber construction, despite expert warnings on potential moisture and decay issues that may affect building performance. In an effort to bridge the knowledge gap, this article presents experimental data on the performance of fungal-decayed cross laminated timber (CLT) connection assemblies. A total of 560 connection assemblies were made using select CLT species from major global markets. These were mechanically tested following inoculation by two brown rot fungi for a total period of 78 weeks, with the connections periodically harvested after 10, 20, 30, 40, 52, and 78 weeks. The data from the mechanical tests, which included cyclic evaluation using an abbreviated CUREE loading protocol and dowel bearing strength tests performed in accordance with ASTM D5764, are submitted in this repository. The repository also contains information on mass changes to connection assemblies as decay progressed and SAWS model parameters that were calibrated using the raw data generated from the universal testing machine (UTM) during cyclic tests of the connection assemblies. This work is fundamental for accurate assessment of fungal deterioration in mass timber buildings and the data submitted herein could be used by researchers and scientists to model behavior of connections in mass timber buildings, especially in humid and damp regions with high chances of biodeterioration.

The aim of this study was to isolate biocontrol bacteria that could antagonize brown rot of Dendrocalamus latiflorus, optimize the culture conditions, and develop an effective biocontrol preparation for brown rot of D. latiflorus. This study isolated a bacterium with an antagonistic effect on bamboo brown rot from healthy D. latiflorus rhizosphere soil. Morphology, molecular biology, and physiological biochemistry methods identified it as Bacillus siamensis. The following culturing media and conditions improved the inhibition effect of B. siamensis: the best culturing media were 2% sucrose, 1.5% yeast extract, and 0.7% potassium chloride; the optimal culturing time, temperature, pH, and inoculation amount were 48 h, 30°C, 6, and 20%. The optimum formula of the applying bacterial suspension was 14% sodium dodecyl benzene sulfonate emulsifier, 4% Na2HPO4·2H2O, 0.3% hydroxypropyl methylcellulose thickener, and 20% B. siamensis. The pot experiment results showed the control effect of applying bacterial suspension, diluted 1,000 times is still better than that of 24% fenbuconazole suspension. The applying bacterial suspension enables reliable control of brown rot in D. latiflorus.

Brown rot disease caused by Monilinia fructicola is one of the most important peach fruit threats in the world. The use of biological control agents (BCAs), instead of synthetic fungicides, to successfully inhibit postharvest disease development is a challenge in sustainable and efficient crop management. The commercially available BCA Bacillus amyloliquefaciens QST 713 (formerly Bacillus subtilis QST713) is able to inhibit a variety of fungal pathogens and suppress several plant diseases. Our results showed that this BCA inhibited mycelial growth in vitro, and was able to suppress the disease's severity in peach fruits via delaying and reducing brown rot symptoms. A transcriptomic analysis of fruits during their pre-treatment with this biocontrol agent following M. fructicola challenge revealed a significant upregulation of specific differentially expressed genes (DEGs) at 48 h after inoculation (HAI). These genes are related to the activation of several transcriptional factors, such as members of the WRKY and NAC families, and receptors that are involved in pathogen recognition and signaling transduction (e.g., LRR-RLKs). Furthermore, the inhibition of M. fructicola by this biocontrol agent was confirmed by analyzing the expression profiles of specific fungal genes, which highlighted the direct antimicrobial impact of this bacterial strain against the fungus. Hence, these findings clearly suggest that B. amyloliquefaciens QST 713 is an efficient BCA against brown rot disease, which can directly inhibit M. fructicola and improve peach fruit tolerance. [ABSTRACT FROM AUTHOR]

Phytophthora citrophthora and P. syringae are currently the primary causal organisms of brown rot of citrus fruits in California. To possibly find an explanation for the prevalence of the previously minor species P. syringae, we determined the population structures of both pathogens in California using next-generation sequencing and population genomics analyses. Whole-genome sequencing and aligning with newly assembled reference genomes identified 972,266 variants in 132 isolates of P. citrophthora and 422,208 variants in 154 isolates (including 24 from noncitrus tree crops) of P. syringae originating from three major growing regions. The resulting data sets were visualized using principal component analysis, discriminant analysis of principal components, unweighted pair-group method with arithmetic mean dendrograms, fastStructure, and minimum spanning networks, and we obtained the index of association, diversity summary statistics, and genetic distance statistics values GST, G′′ST, and Jost's D. Subpopulations of both species were mostly defined by their geographic origin indicating restricted dispersal of inoculum. Except for five isolates, the population structure of P. citrophthora (that is heterothallic and unlikely to reproduce sexually) was clonal to semi-clonal, with very little genetic diversity within and among subgroups. In contrast, the population structure of P. syringae was also clonal to semi-clonal, but isolates were placed into four main clusters of much higher diversity. Clonality in both species can be explained by a high level of asexual reproduction. The higher diversity in the homothallic P. syringae is likely due to commonly occurring sexual reproduction. One distinct cluster of P. syringae consisted solely of isolates from noncitrus hosts; therefore, the origin of P. syringae in citrus could not be resolved. [ABSTRACT FROM AUTHOR]

BACKGROUND: Gnomoniopsis smithogilvyi is the major chestnut pathogen, responsible for economic losses and recently described as a 3‐nitropropionic acid and diplodiatoxin mycotoxin producer. Bacillus amyloliquefaciens QST 713 (Serenade® ASO), B. amyloliquefaciens CIMO‐BCA1, and the fungicide Horizon® (tebuconazole) have been shown to reduce the growth of G. smithogilvyi. However, they enhanced mycotoxin production. Proteomics can clarify the mould's physiology and the impact of antifungal agents on the mould's metabolism. Thus, the aim of this study was to assess the impact of Horizon®, Serenade®, and B. amyloliquefaciens CIMO‐BCA1 in the proteome of G. smithogilvyi to unveil their modes of action and decipher why the mould responds by increasing the mycotoxin production. For this, the mycelium close to the inhibition zone provoked by antifungals was macroscopically and microscopically observed. Proteins were extracted and analysed using a Q‐Exactive plus Orbitrap. RESULTS: The results did not elucidate specific proteins involved in the mycotoxin biosynthesis, but these agents provoked different kinds of stress on the mould, mainly affecting the cell wall structures and antioxidant response, which points to the mycotoxins overproduction as a defence mechanism. The biocontrol agent CIMO‐BCA1 acts similar to tebuconazole. The results revealed different responses on the mould's metabolism when co‐cultured with the two B. amyloliquefaciens, showing different modes of action of each bacterium, which opens the possibility of combining both biocontrol strategies. CONCLUSION: These results unveil different modes of action of the treatments that could help to reduce the use of toxic chemicals to combat plant pathogens worldwide. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Brown rot disease, caused by Monilinia fructicola, poses a significant challenge to peach production in China. The efficacy of mefentrifluconazole, a new triazole fungicide, in controlling brown rot in peaches has been remarkable. However, the resistance risk and mechanism associated with this fungicide remain unclear. This study was designed to assess the resistance risk of M. fructicola to mefentrifluconazole and reveal the potential resistance mechanism. RESULTS: The mean median effective concentration (EC50) of 101 M. fructicola isolates to mefentrifluconazole was 0.003 μg mL−1, and the sensitivity exhibited a unimodal distribution. Seven mefentrifluconazole‐resistant mutants were generated from three parental isolates in the laboratory through fungicide adaption. The biological characteristics of the resistant mutants revealed that three of them exhibited enhanced survival fitness compared to the parental isolates, whereas the remaining four mutants displayed reduced survival fitness. Mefentrifluconazole showed strong positive cross‐resistance with fenbuconazole, whereas no cross‐resistance was observed with pyrimethanil, procymidone or pydiflumetofen. No overexpression of MfCYP51 gene was detected in the resistant mutants. Multiple sequence alignment revealed that three resistant mutants (MXSB2‐2, Mf12‐1 and Mf12‐2) had a point mutation (G461S) in MfCYP51 protein. Molecular docking techniques confirmed the contribution of this point mutation to mefentrifluconazole resistance. CONCLUSION: The risk of M. fructicola developing resistance to mefentrifluconazole is relatively low‐to‐medium and point mutation G461S in MfCYP51 could confer mefentrifluconazole resistance in M. fructicola. This study provided essential data for monitoring the emergence of resistance and developing resistance management strategies for mefentrifluconazole. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Pear brown rot and blossom blight caused by Monilinia laxa seriously affect pear production worldwide. Here, we compared the transcriptomic profiles of petals after inoculation with M. laxa using two pear cultivars with different levels of sensitivity to disease (Sissy, a relatively tolerant cultivar, and Kristalli, a highly susceptible cultivar). Physiological indexes were also monitored in the petals of both cultivars at 2 h and 48 h after infection (2 HAI and 48 HAI). RNA-seq data and weighted gene co-expression network analysis (WGCNA) allowed the identification of key genes and pathways involved in immune- and defenserelated responses that were specific for each cultivar in a time-dependent manner. In particular, in the Kristalli cultivar, a significant transcriptome reprogramming occurred early at 2 HAI and was accompanied either by suppression of key differentially expressed genes (DEGs) involved in the modulation of any defense responses or by activation of DEGs acting as sensitivity factors promoting susceptibility. In contrast to the considerably high number of DEGs induced early in the Kristalli cultivar, upregulation of specific DEGs involved in pathogen perception and signal transduction, biosynthesis of secondary and primary metabolism, and other defense-related responses was delayed in the Sissy cultivar, occurring at 48 HAI. The WGCNA highlighted one module that was significantly and highly correlated to the relatively tolerant cultivar. Six hub genes were identified within this module, including three WRKY transcription factor-encoding genes: WRKY 65 (pycom05g27470), WRKY 71 (pycom10g22220), and WRKY28 (pycom17g13130), which may play a crucial role in enhancing the tolerance of pear petals to M. laxa. Our results will provide insights into the interplay of the molecular mechanisms underlying immune responses of petals at the pear–M. laxa pathosystem. [ABSTRACT FROM AUTHOR]

The type VI secretion system (T6SS) of many gram‐negative bacteria injects toxic effectors into adjacent cells to manipulate host cells during pathogenesis or to kill competing bacteria. However, the identification and function of the T6SS effectors remains only partly known. Pantoea ananatis, a gram‐negative bacterium, is commonly found in various plants and natural environments, including water and soil. In the current study, genomic analysis of P. ananatis DZ‐12 causing brown stalk rot on maize demonstrated that it carries three T6SS gene clusters, namely, T6SS‐1, T6SS‐2, and T6SS‐3. Interestingly, only T6SS‐1 secretion systems are involved in pathogenicity and bacterial competition. The study also investigated the T6SS‐1 system in detail and identified an unknown T6SS‐1‐secreted effector TseG by using the upstream T6SS effector chaperone TecG containing a conserved domain of DUF2169. TseG can directly interact with the chaperone TecG for delivery and with a downstream immunity protein TsiG for protection from its toxicity. TseG, highly conserved in the Pantoea genus, is involved in virulence in maize, potato, and onion. Additionally, P. ananatis uses TseG to target Escherichia coli, gaining a competitive advantage. This study provides the first report on the T6SS‐1‐secreted effector from P. ananatis, thereby enriching our understanding of the various types and functions of type VI effector proteins. [ABSTRACT FROM AUTHOR]

Chestnut nut rots caused by fungi, especially by Gnomoniopsis smithogilvyi, showed a significant increase not only in Turkey but also in the other chestnut‐producing countries. In this study, the prevalence of chestnut kernel rot was determined by using 800 fruits collected from eight significant chestnut‐growing provinces of Turkey located in the Black Sea, Marmara, and Aegean Regions. Six types of kernel rot symptoms were determined from the necrotic nuts, brown rot being the most common accounting for 62% of the necrotic nuts. Along with G. smithogilvyi, seven additional fungal species Colletotrichum fioriniae, C. godetiae, Cryphonectria parasitica, Diplodina agrifoliae, Fusarium concentricum, Fusarium tricinctum, and Trichothecium roseum were found to be associated with kernel rot. In addition, some other ubiquitous fungi such as Penicillium spp. were detected. All the pathogenic fungi were identified through a combination of morphological traits and phylogenetic analysis involving partial internal transcribed spacer (ITS) sequences, as well as tef1 and tub2 loci sequences. The most frequently isolated fungus was G. smithogilvyi, and it was found at 98, 31, 10, and 1 of the necrotic kernels out of 291 showing brown rot, brown to black rot, cream colour decay, and white rot symptoms, respectively. It was not found from the kernels showing green rot and greenly‐blue rot symptoms. G. smithogilvyi was prevalent in six of eight chestnut‐growing locations in Turkey. Based on the findings, G. smithogilvyi was shown to be the main fungal agent of brown kernel rot of chestnuts, and some of the other fungi obtained from the kernels were shown to contribute kernel rots of chestnuts. [ABSTRACT FROM AUTHOR]

We investigated factors affecting the community composition of lignicolous myxomycetes in dead wood with white and brown rot through summer and autumn surveys in a subalpine forest in Central Japan. In both seasons, wood had decayed to a softer state under brown rot than under white rot. The pH of wood with white rot was nearly neutral, while wood with brown rot was weakly acidic. Wood pH was lower in summer than in autumn. Forty-two myxomycetes taxa in 19 genera were identified in 302 fruiting-body colonies; white rot yielded 31 taxa and brown rot 24 taxa. Species diversity was higher on wood with white rot than on wood with brown rot. The effect of wood hardness on species composition depended on season. Several species exhibited a preference for one of the rot types. The substrate conditions associated with brown rot limit myxomycetes species diversity. [ABSTRACT FROM AUTHOR]

Resin production in wood tissues is a regular feature of pine wood species, including southern pine. High resin contents of southern pine wood may increase wood resistance against decay fungi. The current study investigated the effect of resin contents in southern pine wood on decay resistance by exposing non-extracted heartwood, mixed wood (sapwood + heartwood), and sapwood blocks with varying resin content to brown rot, Fomitopsis ostreiformis in a laboratory decay test. Matching blocks of each wood type were successively extracted in a Soxhlet using three solvents to determine resin content and were exposed to decay fungus in parallel. Results showed that mass losses in non-extracted heartwood and mixed wood depended on resin content levels, and very shallow or no mass losses were observed in blocks containing more than 31 % resin content. Sapwood experienced high mass losses, but the presence of resinous extractives significantly increased the decay resistance. All solvent-extracted blocks experienced high mass loss (53–55 %). Scanning electron microscopy showed that penetration of brown rot hyphae and cell damage depended on the resin contents of blocks. Most of the identified compounds through GC-MS belonged to oleoresins, among which monoterpene hydrocarbons, oxygenated monoterpenoids, and sesquiterpenes were more abundant in heartwood than sapwood. [ABSTRACT FROM AUTHOR]

This research aimed to assess the improvements in dimensional stability and resistance to wood decay by treating the wood with a solution of glycerol–maleic anhydride mixture (GLY-MA) without a catalyst, at four concentrations (10%, 15%, 20%, and 25%), followed by heat treatment at 170 °C for 4 h. Four wood species were selected for property testing: two locally grown in Egypt, namely Tree of heaven (Ailanthus altissima, heartwood) and Cypress (Cupressus sempervirens, sapwood), and two imported species, European beech (Fagus sylvatica) and Norway spruce (Picea abies), both heartwood. The treatment conditions reported here proved the effectiveness in enhancing the stabilization against water absorption for all four wood species. All four concentrations improved dimensional stability, with the highest improvement observed with the 25% treatment for all wood species. Although the treatments had a slight effect on decreasing compressive strength and hardness, a clear significant difference was observed at a concentration of 25% compared to untreated samples. The hardness at a 25% concentration was 4434.7 N, 2440 N, 5220 N, and 1440 N for Tree of heaven, Cypress, Beech, and Spruce, respectively. Across all species studied, the use of the four concentrations demonstrated a shift in wood resistance against white rot and brown rot fungi from nonresistant to moderately resistant. Therefore, in terms of cost-effectiveness, it is recommended to use the low concentration, 10% to enhance decay resistance, as this concentration effectively achieves the desired outcome without the need for higher concentrations, in addition to being environmentally friendly. [ABSTRACT FROM AUTHOR]

A freely available Monilinia spp. marker database was created, containing microsatellite (SSR) data of the three most essential European fungal pathogens: M. fructigena, M. laxa, and M. fructicola. These pathogens cause brown rot blossom blight. Microsatellites were identified using the bioinformatics tool Genome-wide Microsatellite Analyzing Toward Application (GMATA). The database provides information about SSR markers: forward and reverse sequences of the primers, fragment sizes, SSR motifs (and repeats), and the exact locations with the coordinates in the reference genome. This database currently contains information about 39,216 SSR motifs and 26,366 markers. In total, eight primers generated in silico were validated experimentally and they are marked in the database. All scientists can join this collaboration by adding their experimental data. This database is the initial start of organizing Monilinia spp. molecular data worldwide and, in the future, it could be extended by adding more molecular and genomic information. [ABSTRACT FROM AUTHOR]

The peach (Prunus persica L.) is one of the most important stone-fruit crops worldwide. Nevertheless, successful peach fruit production is seriously reduced by losses due to Monilinia fructicola the causal agent of brown rot. Chitosan has a broad spectrum of antimicrobial properties and may also act as an elicitor that activate defense responses in plants. As little is known about the elicitation potential of chitosan in peach fruits and its impact at their transcriptional-level profiles, the aim of this study was to uncover using RNA-seq the induced responses regulated by the action of chitosan in fruit–chitosan–M. fructicola interaction. Samples were obtained from fruits treated with chitosan or inoculated with M. fructicola, as well from fruits pre-treated with chitosan and thereafter inoculated with the fungus. Chitosan was found to delay the postharvest decay of fruits, and expression profiles showed that its defense-priming effects were mainly evident after the pathogen challenge, driven particularly by modulations of differentially expressed genes (DEGs) related to cell-wall modifications, pathogen perception, and signal transduction, preventing the spread of fungus. In contrast, as the compatible interaction of fruits with M. fructicola was challenged, a shift towards defense responses was triggered with a delay, which was insufficient to limit fungal expansion, whereas DEGs involved in particular processes have facilitated early pathogen colonization. Physiological indicators of peach fruits were also measured. Additionally, expression profiles of particular M. fructicola genes highlight the direct antimicrobial activity of chitosan against the fungus. Overall, the results clarify the possible mechanisms of chitosan-mediated tolerance to M. fructicola and set new foundations for the potential employment of chitosan in the control of brown rot in peaches. [ABSTRACT FROM AUTHOR]

Brown rot in apples is caused by fungi belonging to the genus Monilinia and occurs annually in orchards with varying severity. The symptoms of the disease on apple fruits may occur during harvest and can also develop much later in storage. Therefore, from a practical point of view, it is very important to be able to test a sample of asymptomatic apples before putting them in storage or sending them to distant markets. Thus, there is a need to develop a quick and sensitive method of detecting disease causal agents in asymptomatically infected fruit. For this purpose, a procedure for DNA isolation from the skin of apples was developed, and a set of primers for the loop‐mediated isothermal amplification (LAMP) reaction was designed based on a fragment of the hsp60 gene encoding heat shock protein 60 of Monilinia fungi that are pathogenic to apple: M. fructigena, M. fructicola and M. polystroma. The method was validated by reactions with DNA from infected apple fruit exhibiting brown rot symptoms and DNA from infected apple fruit without visible brown rot symptoms (latent infection). To increase the sensitivity of detection before the LAMP reaction, preamplification of the target DNA was carried out. The sensitivity of detection in the LAMP assay for the DNA of all three tested species of fungi was 2 pg. The DNA preamplification significantly increased the sensitivity of Monilinia DNA detection to 0.1 pg. This study shows that the developed LAMP method can be used to detect Monilinia fungi in asymptomatically infected apples. [ABSTRACT FROM AUTHOR]

Acetylation is a commercialised chemical wood modification technology that increases the durability of wood against microbial attack. However, the details of how acetylation protects the wood structure from fungal degradation are still unclear. In this study, we tested the hypothesis that the resistance against microbial attack depends on the localisation of acetylation within the cell wall. The methodology involved two types of acetylation (uniform and lumen interface modification), which were analysed by lab-scale degradation with Rhodonia placenta, chitin quantification, infrared spectroscopy, and Raman microspectroscopy. The location of the acetylation did not affect overall mass loss during degradation experiments. Instead, the mass loss was related to the intensity of the treatment. However, chemical imaging of the interface acetylated specimens showed that degradation primarily took place in cell wall regions that were less acetylated. It was also observed that the fungus required more fungal biomass (i.e., fungal mycelia) to degrade acetylated wood than untreated wood. Based on dimensions and comparison to a reference spectrum, several cross-sections of hyphae located within lumina were discovered in the Raman images. These hyphae showed presence of chitin, water and chelated metals within their walls, and could be separated into an inner and an outer part based on their chemistry as seen in the spectra. The outer part was distinguished by a relatively higher amount of water and less chelated iron than the inner part. [ABSTRACT FROM AUTHOR]

Monilinia laxa is one of the most destructive fungal pathogens causing brown rot, blossom blight and spur infection on stone fruits such as peach, nectarine, apricot, cherry and plum. In 2019–2020 surveys, 30 orchards in the apricot and almond production areas of Malatya and Elazıg provinces of Turkey exhibited blossom and twig blight symptoms. The objective of this study was to evaluate the in vitro and in vivo efficacy of boron products, pyroligneous acid and some fungicides on Monilinia laxa. Boron derivatives and boscalid were tested at different concentrations (0.01, 0.03, 0.05, 0.07, 0.09, 0.1,0.2, 0.4, 0.6%; w/v, μg.ml−1) for their inhibitory effect on mycelial growth of M. laxa. Mycelial growth of M. laxa was completely inhibited by boric acid (0.1%), borax (0.09%), Etidot (0.09%), pyroligneous acid (0.8%) and boscalid (0.6 µgml−1). Boric acid (0.12%), borax (0.1%), Etidot-67 (0.15%), PA (1.2%) and boscalid (0.8 µg ml−1) significantly inhibited germination of conidia of M. laxa isolates. EC50 values for 4 isolates of M. laxa ranged from 0.028 to 0.569% (MIC values ranged from 0.09 to 0.8 µgml−1) for mycelial growth and from 0.052 to 0.750% (MIC values ranged from 0.1 to 0.12) for conidial germination. In field trials conducted in the two subsequent years, boscalid + pyraclostrobin showed the highest efficacy (82.4% and 85.2%), followed by PA + borax (64.2% and 65.6%), PA + boric acid (48.2% and 54.6%), and boric acid + borax (18.2% and 21.9%, respectively). [ABSTRACT FROM AUTHOR]

This article reports on the first occurrence of Penicillium sclerotigenum causing post-harvest rot of yam in Côte d'Ivoire. Yam is a significant non-cereal food crop in the country, with Côte d'Ivoire being the world's third-largest producer. Previous studies have identified various fungi responsible for post-harvest rots in yams. Surveys conducted in two cities in Côte d'Ivoire revealed yam tubers exhibiting symptoms of dry brown rot. Morphological and molecular analyses confirmed the presence of Penicillium sclerotigenum as the causal agent. Further monitoring is needed to assess losses and varietal resistance. This research was funded by the Partnership for Skills in Applied Sciences, Engineering, and Technology Regional Scholarship and Innovation Fund (PASET-RSIF). [Extracted from the article]

The plum tree (Prunus domestica L.) is the dominant fruit tree species in Romania, according to the FAOSTAT (2021) data base. Globally, Romania ranks the second place after China at the top of major plum growing countries. This species is susceptible to various economically impactful diseases such as brown rot, produced by Monilinia spp. Climatic conditions have an important role in the occurrence and frequency of disease damage depending of a cultivar. Therefore, in 2023 at the FRDS Bistrita, was monitored the behaviour of brown rot damage on 18 plum cultivars with different ripening periods. During the growing stage, 12 conventional phytosanitary treatments were applied up to the harvest time. The determinations were made in the field after fruit harvesting, at the consumer's ripeness stage. Expectedly, the response to brown rot infection on fruits was different through all the cultivars studied. The results revealed low infections with Monilinia spp. on ‘Zamfira’ (6.9%), ‘Anna Späth’ (7.0%), and ‘Doina’ (7.7%), while ‘Matilda’ (39.5%), ‘Elena’ (33.1%), and ‘Jubileu 50’ (31.9%) expressed symptoms and a higher percentage of infected fruits. All the data obtained are statistically supported. The results are encouraging, allowing a selection of resistant or tolerant cultivars to brown rot, considering the increasing impact of climate change. Furthermore, the global trend toward organic farming requires the use of resistant cultivars to problematic pathogens for successful farming.

Gastrodia elata, commonly known as Tian Ma, is a perennial mycoheterotrophic orchid. Qianyang Tian Ma (QTM), a geographical indication agricultural product from Hongjiang City, Hunan Province, China, is primarily characterized by the red variety, G. elata f. elata. A severe outbreak of tuber brown rot disease was documented in QTM during the harvesting season in Hunan. The fungal pathogen associated with the disease was isolated on potato saccharose agar (PSA) and identified through morphological and phylogenetic analyses. Pathogenicity tests were performed on healthy tubers of G. elata f. elata. The results showed that the representative isolate, named TMB, produced white hyphal colonies with a ring structure, broom-like phialides, partially curved ellipsoidal conidia, and orange–yellow spherical ascocarps on PSA. Phylogenetic analysis of the ITS, LSU, rpb2 and tub2 sequences using Bayesian and maximum-likelihood methods identified the isolate TMB as Clonostachys rosea, based on morphological and phylogenetic data. Pathogenicity tests revealed typical disease symptoms on healthy G. elata tubers 15 days post-inoculation with the isolate TMB. C. rosea is known to cause diseases in economically important crops, but there are no reports of its occurrence on G. elata f. elata in China. This study provides valuable insights into the occurrence, prevention, and control of brown rot disease in G. elata f. elata.