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Introduction: Species of Botryosphaeriaceae fungi are relevant pathogens of almond causing trunk cankers, extensive gumming, necrosis of internal tissues and plant dieback and dead, threatening almond productivity. A novel triplex quantitative real-time PCR (qPCR) assay was designed for the simultaneous detection and quantification of Neofusicoccum parvum, Botryosphaeria dothidea and the Botryosphaeriaceae family. Material and methods: The method was validated in symptomatic and asymptomatic almond, avocado, blueberry and grapevine plants and in environmental samples, such as cropping soil and rainwater and in artificially inoculated trapped spores, demonstrating the same performance on several matrices. Results and discussion: The limit of detection of the triplex qPCR was 10 fg of genomic DNA for the three fungal targets, with high correlation coefficients (R2) and amplification efficiencies between 90 and 120%. Although the triplex qPCR demonstrated to be more sensitive and accurate than the traditional plate culturing and further sequencing method, a substantial agreement (kappa index = 0.8052 ± 0.0512) was found between the two detection methods. The highly sensitive qPCR assay allows for accurate diagnosis of symptomatic plants and early detection of Botryosphaeriaceae fungi in asymptomatic plants (rootstocks and grafting scions from almond nurseries). Furthermore, the triplex qPCR successfully detected Botryosphaeriaceae fungi in environmental samples, such as cropping soils and rainwater. It was also capable of detecting as few as 10 conidia in artificially inoculated tapes. Therefore, the triplex qPCR is a valuable tool for accurate diagnosis, aiding in the implementation of suitable control measures. It enables preventive detection in asymptomatic samples, helping to avoid the introduction and spread of these pathogens in production fields. Moreover, it assists in identifying inoculum sources and quantifying inoculum levels in crop environments, contributing to a precise phytosanitary application schedule, thereby reducing production costs and preserving the environment. [ABSTRACT FROM AUTHOR]

Ficus hirta Vahl is an important medicinal and edible plant in southern China. Typical green wilting on leaves and brown necrotic spots on the stems were observed since mid-June 2022 in an F. hirta plantation in Danzhou, Hainan (China). The disease rapidly developed, causing stem withering and plant death. The disease incidence varied from 45 to 85% prevalence, and the average disease index was 47 in the period of outbreak during June to December. Relevant hypothetical fungi were isolated from naturally infected wilt tissues, and their pathogens were preliminarily confirmed to be Lasiodiplodia pseudotheobromae through hypothetical fungal culturing, morphological characteristic observations, and pathogenicity testing on F. hirta plants. The phylogenetic tree constructed based on partial ITS, translation elongation factor (TEF1-α), and the β-tubulin gene (TUB2) further confirmed the identity of the pathogen as L. pseudotheobromae. Further research on the biological characteristics of L. pseudotheobromae showed that the optimal temperature for the growth of L. pseudotheobromae was PDA medium, with a temperature of 30 °C and pH of 6. Peptone and fructose were the optimal nitrogen and carbon sources for it. In vitro efficacy testing showed that among eleven fungicides, fluazinam and prochloraz had the highest mycelial growth inhibition, with an EC50 of 0.0477 µg/mL and 0.0996 µg/mL, respectively. And the two fungicides showed significant control on the stem wilt of F. hirta in a pot. To our knowledge, this is the first comprehensive report on the pathogen identification and biological characteristics of L. pseudotheobromae infecting the stem wilt of F. hirta in China. Our results provide important information for developing effective management measures and controlling this disease. [ABSTRACT FROM AUTHOR]

The fungi Botryosphaeriaceae are involved in olive declines in both the world hemispheres and in all continents where this species is cultivated. In Salento (Apulia, Italy), the Botryosphaeriaceae Neofusicoccum mediterraneum and N. stellenboschiana have been reported as the agents of a branch and twig dieback that overlaps with olive quick decline syndrome caused by Xylella fastidiosa subsp. pauca. In this study, we report the finding of Diplodia seriata, another Botryosphaeriaceae species, in Salento in Xylella fastidiosa-infected olive trees affected by symptoms of branch and twig dieback. Given that its presence was also reported in olive in the Americas and in Europe (Croatia) with different degrees of virulence, we were prompted to assess its role in the Apulian decline. We identified representative isolates based on morphological features and a multilocus phylogeny. In vitro tests showed that the optimum growth temperature of the isolates is around 25–30 °C, and that they are highly thermo-tolerant. In pathogenicity trials conducted over eleven months, D. seriata expressed a very low virulence. Nonetheless, when we imposed severe water stress before the inoculation, D. seriata significatively necrotized bark and wood in a time frame of 35 days. Moreover, the symptoms which resulted were much more severe in the trial performed in summer compared with that in autumn. In osmolyte-supplemented media with a water potential from −1 to −3 Mpa, the isolates increased or maintained their growth rate compared with non-supplemented media, and they also grew, albeit to a lesser extent, on media with a water potential as low as −7 Mpa. This suggests that olives with a low water potential, namely those subjected to drought, may offer a suitable environment for the fungus' development. The analysis of the meteorological parameters, temperatures and rainfall, in Salento in the timeframe 1989–2023, showed that this area is subjected to a progressive increase of temperature and drought during the summer. Thus, overall, D. seriata has to be considered a contributor to the manifestation of branch and twig dieback of olive in Salento. Coherently with the spiral decline concept of trees, our results suggest that heat and drought act as predisposing/inciting factors facilitating D. seriata as a contributor. The fact that several adverse factors, biotic and abiotic, are simultaneously burdening olive trees in Salento offers a cue to discuss the possible complex nature of the olive decline in Salento. [ABSTRACT FROM AUTHOR]

Summary. Grapevine cultivation in Mexico is important, especially in the states of Baja California and Coahuila, which are the main wine production regions in the country. Grapevine trunk diseases (GTDs) impact productivity and cause substan- tial economic losses, with Botryosphaeria dieback being one of the most destructive. This disease is caused by fungi in the Botryosphaeriaceae, including species of Botry- osphaeria, Diplodia, Lasiodiplodia, and Neofusicoccum. To date, Lasiodiplodia spp. are the primary Botryosphaeriaceae fungi reported in Mexico. The present study aimed to enhance the epidemiological knowledge of Botryosphaeriaceae in Mexican vineyards. Samples from grapevine plants exhibiting disease symptoms were collected from the states of Baja California and Coahuila. Of a total of 37 Botryosphaeriaceae isolates, six species were identified: Neofusicoccum parvum, N. australe, N. vitifusiforme, Botry- osphaeria dothidea, Diplodia corticola, and D. seriata. Neofusicoccum parvum isolates were the most virulent, but were less virulent than previously reported Lasiodiplodia spp. The optimum growth temperatures for N. parvum and B. dothidea were from 28 to 30°C, but 25°C for D. seriata, N. vitifusiforme, and N. australe isolates. Only D. seria- ta isolates recovered growth when transferred to room temperature after exposure to 37°C or 40°C. This report is the first identification of B. dothidea and N. parvum as causative agents of Botryosphaeria dieback in the vine-growing regions of Mexico. [ABSTRACT FROM AUTHOR]

During 2021 and 2022, a field investigation was conducted in Istria, Croatia, searching for trees exhibiting signs of Botryosphaeria dieback. Samples of symptomatic trees were collected from 26 different locations and analysed. Isolates that morphologically corresponded to species from the Botryosphaeriaceae family were selected, and detailed morphological characterisation and molecular identification of the isolates were conducted. Based on morphological characteristics and phylogenetic analysis using the internal transcribed spacer (ITS), beta-tubulin (TUB2), and translation elongation factor 1-alpha (TEF1-α) regions, six species of fungi from the Botryosphaeriaceae family were identified: Botryosphaeria dothidea (Moug. ex Fr.) Ces. & De Not.; Diplodia mutila (Fr.) Fr.; Diplodia seriata De Not.; Dothiorella iberica A.J.L. Phillips, J. Luque & A. Alves; Dothiorella sarmentorum (Fr.) A.J.L. Phillips, Alves & Luque; and Neofusicoccum parvum (Pennycook & Samuels) Crous, Slippers & A.J.L. Phillips. This is the first report of D. mutila, Do. sarmentorum, and Do. iberica causing Botryosphaeria dieback on olive trees in Croatia, and the first study investigating the resistance of Croatian olive varieties to species from the Botryosphaeriaceae family. Pathogenicity testing of selected isolates and assessment of variety resistance were conducted on four different olive varieties, namely Buža, Istarska bjelica, Leccino, and Rosinjola, using representative isolates of the mentioned species. The most aggressive species was found to be N. parvum. Olive varieties exhibited differences in susceptibility depending on the fungus they were infected with. [ABSTRACT FROM AUTHOR]

Mexico ranks second in the world for Persian lime (Citrus latifolia) exports, making it the principal citrus exporter within the national citrus industry, exporting over 600,000 tons per year. However, diseases are the main factor reducing production, resulting in significant economic losses. Among these diseases, fungal diseases like dieback, caused by species of Lasiodiplodia, are an emerging issue in Persian lime. Symptoms include gummosis, twig and branch dieback, cankers, the necrosis of bark and wood, fruit mummification, and tree decline. The aim of this study was to investigate the occurrence and pathogenicity of the fungal species associated with twig and branch dieback, cankers, and decline of Persian lime trees in southern Mexico, and to elucidate the current status of the Lasiodiplodia species causing the disease in Mexico. During June, July, and August of 2023, a total of the 9229 Persian lime trees were inspected across 230 hectares of Persian lime orchards in southern Mexico, and symptoms of the disease were detected in 48.78% of the trees. Branches from 30 of these Persian lime trees were collected. Fungal isolates were obtained, resulting in a collection of 40 strains. The isolates were characterized molecularly and phylogenetically through the partial regions of four loci: the internal transcribed spacer region (ITS), the β-tubulin gene (tub2), the translation elongation factor 1-alpha gene (tef1-α), and the DNA-directed RNA polymerase II second largest subunit (rpb2). Additionally, pathogenicity was assessed, successfully completing Koch's postulates on both detached Persian lime branches and certified 18-month-old Persian lime plants. Through multilocus molecular phylogenetic identification, pathogenicity, and virulence tests, five species were identified as causal agents: L. iraniensis, L. lignicola, L. mexicanensis, L. pseudotheobromae, and L. theobromae. This study demonstrates that in southern Mexico, at least five species of the genus Lasiodiplodia are responsible for dieback in Persian lime. Additionally, this is the first report of L. lignicola and L. mexicanensis as causal agents of the disease in citrus, indicating novel host interactions between species of Lasiodiplodia and C. latifolia. [ABSTRACT FROM AUTHOR]

The cultivated apple (Malus × domestica) is one of Türkiye's most important economic crops. Over the growing seasons of 2020–2022, typical symptoms of branch cankers and scaling-off of the bark on apple trees were observed in the Eğirdir district of Isparta province. Botryosphaeriaceae fungi were consistently isolated from symptomatic branches. The fungal pathogen was identified as Diplodia bulgarica based on cultural and morphological characteristics and ITS region of DNA sequence data comparisons. Pathogenicity tests were performed on detached shoots by inoculating them with mycelial plugs. Diplodia bulgarica isolates caused necrotic lesions on Scarlet Spur apple detached shoots. To aid in the development of control strategies for this fungus, nine fungicides were examined in vitro for their antifungal effects against the pathogen at different concentrations. Chlorothalonil, tebuconazole, thiophanate-methyl, and fluazinam were the most efficient fungicides, with EC50 values were <1.0 µg/mL. [ABSTRACT FROM AUTHOR]

Purpose: The continuing search for more efficient, low-cost enzymes for biomass hydrolysis is a crucial issue in plant biorefining. Due to their ability to secrete a broad set of plant cell-wall degrading enzymes, phytopathogenic wood-colonizing fungi depict a promising source of lignocellulolytic enzymes. However, the use of phytopathogenic fungal enzymes in plant biorefining remains poorly explored. Here, we assessed the capacity of lignocellulolytic enzymes produced by the grapevine trunk pathogen Neofusicoccum parvum in the breakdown of non-pretreated wheat straw (WS) and grapevine canes (GP) after growth on these two substrates. Methods: First, we determined the peak activity time of lignocellulases during 42 days of cultivation. In addition, transcriptomics at late growth stages was performed. Second, we evaluated the performance of secreted enzymes from the WS (WS-S) and GP (GP-S) cultures in hydrolyzing both lignocellulose substrates. Results: Most of the enzymes reached the maximum activity between 14 and 28 days post-inoculation. Enzyme assays combined with transcriptomics revealed a dynamic enzyme utilization, where (hemi-)cellulases were predominantly produced at early growth stages. Afterward, enzymes acting on more recalcitrant polymers became more prominent. The WS-S released more xylose, arabinose, and total sugars from WS (3.3, 7.4, and 4.9% yields, respectively) than GP-S, although the latter generated more glucose from GP (2.4% yield). The sugar yields produced by N. parvum enzymes, particularly on WS hydrolysis, were comparable with those reported for typical industrial-use fungi, such as Aspergillus and Trichoderma spp. Conclusion: These findings suggest that N. parvum may be a helpful source of lignocellulolytic enzymes for plant biorefining. Statement of Novelty: The efficient enzymatic conversion of lignocellulose to fermentable sugars is one of the major bottlenecks in plant biorefining. That has led to a constant search for novel lignocellulolytic enzymes. Plant pathogens represent a rich but little exploited source of cell wall-degrading enzymes. This work shows that lignocellulolytic enzymes from the fungal trunk pathogen Neofusicoccum parvum performed comparatively well in converting non-pretreated wheat straw and grapevine canes into monomeric sugars. Our results suggest that both agricultural residues can be used as a cheap carbon source for producing enzymes of interest for plant biorefining, which may contribute to their valorization, particularly for the less explored grapevine pruning residues. In addition, we described a temporal utilization of lignocellulolytic enzyme in N. parvum. Highlights: Temporal dynamics in lignocellulolytic enzyme activities from N. parvum. Up-regulation of CAZymes-coding genes after long-term in vitro cultivation. N. parvum enzymes seem promising for hydrolysis of non-pretreated lignocellulose. [ABSTRACT FROM AUTHOR]

Botryosphaeriaceous fungi are widespread, and cause serious diseases in many economically important crops. Botryosphaeria dothidea, Neofusicoccum mediterraneum and N. parvum are the most important members of this family in the Mediterranean region. These fungi are frequently isolated from the same host, which together with their extensive and increasing host range necessitates development of rapid and reliable diagnostic tools. Species boundaries within the Botryosphaeriaceae have been defined based on phylogenetic analyses of multiple gene sequences, including those of mating type genes. The MAT1-2-1 gene displayed high sequence variability between Botryosphaeriaceous species, so was selected as the target for development of a definitive diagnostic tool. This paper outlines a new and robust molecular tool, composed of three TaqMan assays based on polymorphisms located in the MAT1-2-1 gene of B. dothidea, N. mediterraneum and N. parvum. Each assay differentiated the target species from other Botryosphaeriaceae, and from non-target fungi. [ABSTRACT FROM AUTHOR]

Trunk canker poses a major threat to the production of Chinese hickory tree (Carya cathayensis Sarg.), which is primarily determined by Botryosphaeriaceae. In our previous work, we identified Botryosphaeria dothidea as the predominant pathogen of this disease. However, it is still unclear about corresponding gene families and mechanisms associated with B. dothidea's pathogenicity on Chinese hickory tree. Here, we present a comparative analysis of high-quality genome assemblies of Botryosphaeria dothidea and other isolated pathogens, showing highly syntenic relationships between B. dothidea and its closely related species and the conservative evolution of the Botryosphaeriaceae family. Higher GC contents were found in the genomes of B. dothidea and three other isolated pathogens (Botryshaeria cortices, Botryshaeria fabicerciana, and Botryshaeria qingyuanensis) compared to Macrophomina phaseolina, Neofusicoccum parvum, Diplodia corticola, and Lasiodiplodia theobromae. An investigation of genes specific to or expanded in B. dothidea revealed that one secreted glucanase, one orsellinic acid biosynthesis enzyme, and two MFS transporters positively regulated B. dothidea's pathogenicity. We also observed an overrepresentation of viral integrase like gene and heterokaryon incompatibility proteins in the B. dothidea's genome. In addition, we observed one LRR-domain-containing protein and two Sec-domain-containing proteins (Sec_1 and Sec_7) that underwent positive selection. This study will help to understand B. dothidea's pathogenicity and potential influence on the infection of Chinese hickory, which will help in the development of disease control and ensure the security of Chinese hickory production. [ABSTRACT FROM AUTHOR]

Florida ranks among the most important citrus growing regions in the USA. The present study investigates the occurrence, diversity, and pathogenicity of fungal species associated with symptomatic sweet orange (Citrus sinensis) cv. Valencia plants and fruit. The survey was conducted on twigs and fruit collected in Southwest Florida during 2022. Based on morphological and molecular characteristics, the identified isolates belonged to the species Lasiodiplodia iraniensis, Diaporthe pseudomangiferae, and Diaporthe ueckerae. The pathogenicity of representative isolates was evaluated on citrus fruit and plants. Lasiodiplodia iraniensis was the most virulent on fruit and plants, followed by Diaporthe pseudomangiferae. Diaporthe ueckerae had the lowest virulence on fruit, and it was not pathogenic to plants. In vitro tests were performed to assess the effect of temperature on mycelial radial growth. The optimum temperature of growth ranged from 26.0 to 28.4 °C for all the evaluated species, and L. iraniensis showed the fastest mycelial growth. This study represents the first report of L. iraniensis as a causal agent of tree dieback and fruit stem-end rot on C. sinensis worldwide. Moreover, D. pseudomangiferae and D. ueckerae are reported here for the first time in association with citrus diseases worldwide. [ABSTRACT FROM AUTHOR]

Dieback of fruiting spurs, stems and branches of walnut trees (Juglans regia L.), caused by Botryosphaeriaceae, is widespread in walnut orchards in Australia. Five species of Botryosphaeriaceae (Diplodia seriata, Dothiorella omnivora, Neofusicoccum macroclavatum, N. parvum, and Spencermartinsia viticola) were recovered from the Australian walnut orchards in a previous study, with D. seriata and N. parvum being the most prevalent. The present study evaluated inhibitory effects of ten fungicides on mycelium growth of those five species and on conidium germination of D. seriata and N. parvum. It investigated the preventative and curative efficacy of selected fungicides on disease incidence in glasshouse and field trials. In vitro experiments showed that nine of the fungicides reduced mycelium growth, and all ten inhibited conidium germination, but to varying extents. Tebuconazole, prochloraz manganese chloride, fluazinam, fludioxonil and pyraclostrobin were the most effective for inhibiting mycelium growth (EC50 < 0.14 µg a.i. mL-1), whereas pyraclostrobin, fluxapyroxad, fluopyram, penthiopyrad and tebuconazole were the most effective for inhibiting conidium germination (EC50 < 2.2 µg a.i. mL-1). In planta experiments with five fungicides confirmed that preventative treatments had greater efficacy than curative treatments. A field trial with four commercial fungicide formulations demonstrated that tebuconazole and tebuconazole + fluopyram provided protection of walnut trees for the longest period. The field trial also confirmed the efficacy of pyraclostrobin and the inhibitory effect of fluazinam. This study is the first in Australia to evaluate fungicides in different classes and with different modes of action for efficacy against Botryosphaeriaceae recovered from walnut orchards in Australia, and provides a wider selection of active ingredients for a fungicide rotation programme than that which is currently available to the Australian walnut industry. [ABSTRACT FROM AUTHOR]

Lavender is an oil-bearing plant, which has long been cultivated for oil, fresh flowers, dried products, and food. Leaf blight disease was observed on 'Bandera Pink', which belongs to Lavandula stoechas in Yining County, Xinjiang Uygur Autonomous Region, China. The causal agent of this disease was isolated, and Koch's postulates were assessed to confirm its pathogenicity. The morphological characteristics of the pathogen were observed, and the LSU, ITS, tef1, and tub2 loci were combined and analyzed. Based on morphological characterization and phylogenetic analyses, the causal agent was identified as a fungal species named Dothiorella sarmentorum. Pathogenicity tests revealed that D. sarmentorum can infect seven varieties of three lavender species. This is the first report of D. sarmentorum causing lavender leaf blight. This study provides a theoretical basis for the diagnosis of disease and the monitoring of disease occurrence and epidemics. [ABSTRACT FROM AUTHOR]

Peach (Prunus persica L.) is one of the most important and oldest stone fruits grown in China. Even though P. persica is one of the most commonly grown stone fruits in China, little is known about the biodiversity of microfungi associated with peach branch diseases. In the present study, samples were collected from a wide range of peach growing areas in China, and fungal pathogens associated with peach branch diseases were isolated. In total, 85 isolates were obtained and further classified into nine genera and 10 species. Most of the isolates belonged to Botryosphaeriaceae (46), including Botryosphaeria, Diplodia, Neofusicoccum, Phaeobotryon, and Lasiodiplodia species; Ascochyta, Didymella, and Nothophoma species representing Didymellaceae were also identified. Herein, we introduce Ascochyta prunus and Lasiodiplodia pruni as novel species. In addition, we report the first records of Nothophoma pruni, Neofusicoccum occulatum, and Phaeobotryon rhois on peach worldwide, and Didymella glomerata, Nothophoma quercina, and Phaeoacremonium scolyti are the first records from China. This research is the first comprehensive investigation to explore the microfungi associated with peach branch disease in China. Future studies are necessary to understand the pathogenicity and disease epidemiology of these identified species. [ABSTRACT FROM AUTHOR]

Botryosphaeriaceae (Botryosphaeriales, Dothideomycetes, Ascomycota) encompasses commonly encountered opportunistic pathogens that cause stem cankers on woody plants. Lifestyles of Botryosphaeriaceae species could vary as endophytes, pathogens and saprobes and one species can have one or more lifestyles. Therefore, this family is an excellent candidate to study the relationships among lifestyles and lifestyle changes. It is postulated that this family has saprobic ancestors, and the mechanisms by which they evolved from nonpathogenic ancestors to woody pathogens remain unclear. Here, we present an analysis of 18 Botryosphaeriaceae genomes, including four newly generated high-quality genomes of Botryosphaeriaceae strains. We compared Botryosphaeriaceae genomes with phylogenetically closely related Dothideomycetes taxa including plant pathogens and saprobes which revealed significant net gene family expansion in Botryosphaeriaceae. This gene expansion is prominent in the early ancestors before the divergence of genera of Botryosphaeriaceae. This expansion affected the pathogenicity-related genes and detoxification genes. Furthermore, we analysed horizontal gene transfer, which is a mechanism of transfer to genetic material between organisms that are not in a parent–offspring relationship and identified widespread putative intra-kingdom horizontal gene transfer events in this family. Most were transferred during the evolution of ancient ancestors of Botryosphaeriaceae, before the divergence of the modern genera and were enriched in pathogenicity-related genes and detoxification genes. Furthermore, The RNA sequencing analysis of the Botryosphaeriaceae species Lasiodiplodia theobromae revealed that pathogenicity-related genes and detoxification genes, including those obtained through gene family expansion and horizontal gene transfers, were significantly induced after the infection of plant hosts rather than before infection. These insights reveal critical roles for gene family expansion and horizontal gene transfers in the evolutionary adaptation of Botryosphaeriaceae in the infection of woody plants. We postulate that the pathogenic lifestyle of Botryosphaeriaceae species evolved from saprobic or endophytic lifestyles in the early divergence of this family. However, there are few endophytic genomes available for closely related species of Botryosphaeriaceae, thus further studies are necessary to clarify the evolutionary relationships of the endophytes. [ABSTRACT FROM AUTHOR]

Production from crops of pome, stone fruit, nut, berry fruit, citrus, grapevine, and olive is increasingly threatened by fungal trunk diseases (FTD). These diseases and the consequent production losses are major problems. Many fungi (including Botryosphaeriaceae, Calosphaeriaceae, Diaporthaceae, Diatrypaceae, Nectriaceae, Phaeomoniellaceae, Pleosporaceae, Togniniaceae, Valsaceae) infect host wood, mainly through wounds and subsequent colonization of woody tissues, causing symptoms such as cankers, gummosis, wood rotting, blight and dieback. Propagative plant material, seedlings and fruit play a significant role in pathogen spread. Several abiotic factors (e.g. shifts in cultural practices and climate change) are involved in the disease development. This paper reviews recent literature on FTD of fruit crops, particularly focusing on the European status of pathogen occurrence. Case studies are described related to diseases of apple, citrus, grapevine, berry, nut and stone fruit, and olive trees. Aspects related to epidemiology and the increase in disease incidence along with the future perspectives on the FTD research are also discussed. [ABSTRACT FROM AUTHOR]

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A severe dieback of flowering ash (Fraxinus ornus L.) has been observed in north-central Italy in the last decades. Symptoms include typical sunken, light-brown cankers on the stem and branches; vascular discoloration; tip and shoot dieback; and foliage necroses. The disease was more evident at the beginning of the growing season, and more severe on young regeneration. Six Botryosphaeriaceae species were consistently isolated from symptomatic plant tissues: Botryosphaeria dothidea, Diplodia fraxini, Diplodia subglobosa, Dothiorella iberica, Dothiorella omnivora and Neofusicoccum parvum. B. dothidea and D. fraxini expressed higher aggressiveness and showed a widespread incidence, being the species most frequently associated with cankers; the other four species were less virulent and more erratic, occurring mainly on succulent branch tips and foliage. Isolates were characterized using morphological and molecular approaches (colony/conidial phenotyping and rDNA-ITS genotyping). Phylogenetic analysis provided congruent phylogenies depicting the relationships of the six taxa with the most closely related conspecifics. Pathogenicity tests on 2-year-old seedlings confirmed the higher virulence of B. dothidea and D. fraxini. Extensive, multi-year field surveys at different sites supported the hypothesis that climatic vagaries, mainly heat, water and drought stresses, impaired tree health and vigor, facilitating infection and pervasive colonization by these Botryosphaeriaceae species. Environmental stressors are thus the key factor bringing the six fungal pathogens together in a multitrophic interaction with F. ornus in a novel, lethal fashion. [ABSTRACT FROM AUTHOR]

In recent years, an unusual decline and mortality has been observed in Paulownia plantations throughout the Marche region (Central Italy). Given the economic importance of this emerging forest crop, a study was conducted to determine which pathogens are directly involved in this syndrome. Field surveys performed in two plantations revealed the widespread occurrence of severe disease symptoms such as leaf chlorosis, crown thinning, shoot and branch dieback, sunken cankers, epicormic shoots and root rot. Disease incidence was also assessed by aerial remote sensing (RS) technologies using drones. Symptomatic samples collected from both stem and root tissues yielded fungal and fungal-like colonies representing two distinct families: Botryosphaeriaceae and Peronosporaceae. Morphological and DNA sequence data revealed five distinct species, identified as Macrophomina phaseolina and Botryosphaeria dothidea (Botryosphaeriaceae), Phytophthora pseudocryptogea, P. citrophthora and P. erythroseptica (Peronosporaceae). Given that all species are reported here for the first time on Paulownia, Koch's postulates were satisfied inoculating the three Phytophthora species and two Botryosphaeriaceae at the collar of the stem of potted 1-year-old rooted cuttings in June 2023. Thirty days after inoculation, all plants showed the same symptoms as those observed in the field. [ABSTRACT FROM AUTHOR]

Many fungi belonging to Botryosphaeriaceae are well-known as causal agents of diseases in economically and ecologically important agricultural crops and forest trees. In Italy, the high diffusion of Botryosphaeriaceae infections observed over the last decade, has shown the importance of this group of fungi, which are becoming limiting factors for plant production in agricultural systems, nurseries and natural and urban landscapes. Global warming and stress factors such as occasional extreme climatic events can affect the susceptibility of host plants, as well as fungus behaviour, increasing the risk of future infections. Available reports of Botryosphaeriaceae in Italy have been examined, focusing on wood and fruit pathogens, resulting in a list of ten genera and 57 species. Diplodia is the most widespread genus in Italy with 76 records on 44 hosts, while at species level, Neofusicoccum parvum, Botryosphaeria dothidea and Diplodia seriata show the widest host ranges and many records. The ability of the pathogens to remain latent on asymptomatic plants, and uncontrolled trade of plant materials among countries, facilitate the dissemination and potential introduction of new Botryosphaeriaceae species. Preventive detection and adequate control strategies are always needed to limit the potential damage caused by Botryosphaeriaceae. This review had particular emphasis on host-pathogen associations, disease symptoms, geographic distribution, metabolite production, and accurate pathogen identification. [ABSTRACT FROM AUTHOR]

This article reports the first occurrence of Lasiodiplodia theobromae causing leaf blight on Coffea canephora (robusta coffee) in the Philippines. The disease was observed in a coffee plantation in the Soccsksargen region, which is a major coffee production area in the country. The symptoms included brown to black necrotic lesions on the leaf margins, with a 100% incidence rate among the trees. The fungus was isolated and identified as L. theobromae based on its morphological and genetic characteristics. This finding highlights the need for management strategies to mitigate the impact of the disease on coffee production. [Extracted from the article]

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.)

Species in the Botryosphaeriaceae are common plant pathogens, endophytes, and saprobes found on a variety of mainly woody hosts. Botryosphaeriaceae is a high-profile fungal family whose genera have been subjected to continuous revisions in recent years. Surveys conducted during 2019 and 2020 on several decaying woody hosts (from dead arial twigs, branches, stems, bark, and seed pods) in China and Thailand revealed a high diversity of Botryosphaeriaceae fungi. Identification of 16 Botryosphaeriaceae isolates was carried out based on both morphological characteristics and phylogenetic analyses of combined ITS, LSU, tef1-α, and tub2 sequence data. Four novel species (Dothiorella ovata, Do. rosacearum, Do. septata, and Lasiodiplodia delonicis) and seven previously known species (Botryosphaeria fujianensis, Diplodia mutila, Di. seriata, L. crassispora, L. mahajangana, Macrophomina euphorbiicola and Sphaeropsis eucalypticola) were identified while new hosts and geographical records were reported. This study indicates that the fungal family Botryosphaeriaceae seems to be common and widespread on a broad range of hosts in China and Thailand. [ABSTRACT FROM AUTHOR]

Summary: During the winter of 2022, camphor trees (Cinnamomum camphora L.) showing symptoms of canker, wood discoloration and twig dieback were detected in a nursery located in Catania province of eastern Sicily, Italy. Samples were brought to the laboratory, and isolations revealed the presence of Botryosphaeriaceae spp. in symptomatic wood tissues. Representative isolates were sub-cultured and identified by sequencing. Specifically, the three loci (ITS, tef-1α, and tub2) were amplified by conventional PCR and sequenced. Phylogenetic analysis using the Maximum parsimony approach revealed that nine isolates were strongly clustered within the clade of Neofusicoccum parvum and one isolate within the clade of N. luteum. Pathogenicity tests were conducted by inoculating stems of 1-year-old camphor trees with mycelial plugs of three representative isolates of N. luteum and N. parvum. Nine days after the inoculation, the camphor trees showed the same symptoms as those observed in the nursery. To the best of our knowledge, this is the first report worldwide of N. luteum and N. parvum causing disease in camphor tree. [ABSTRACT FROM AUTHOR]

Shoot blight and branch dieback of English walnut has been associated with a broad diversity of Botryosphaeriaceae and Diaporthe fungi worldwide. These pathogens affect both wood and fruit tissues, infecting the tree through mechanical or natural wounds. Fruit infections can play an important role in the life cycle of the disease. Thus, the effects of cultivar, and fruit maturity on English walnut fruit infection by Botryosphaeriaceae (Botryosphaeria dothidea, Neofusicoccum mediterraneum and N. parvum) and Diaporthe (Diaporthe neotheicola and Dia. rhusicola) fungi were evaluated. The infection and disease progress from inoculated attached fruits or by inoculating fruit abscission wounds was evaluated both under laboratory and field conditions. An initial experiment evaluating two inoculation methods was conducted, but there were not significant differences in disease severity between inoculations with mycelial plugs or conidial suspensions. A total of eight cultivars were selected to evaluate their susceptibility to fruit infection, with 'Chandler' being the most susceptible for all the pathogens tested compared to the other cultivars. Botryosphaeriaceae showed higher aggressiveness on fruit collected at beginning- or middle summer, while Diaporthe showed similar aggressiveness regardless of fruit maturity stage. Botryosphaeriaceae fungi were able to colonize the entire surface of the inoculated fruit, reaching the peduncle and infecting the attached shoot; while Diaporthaceae fungi were not able to colonize the surface of the inoculated fruit quickly enough to infect the attached shoot before the peduncle was naturally separated from the shoot. Finally, we demonstrated that both Botryosphaeriaceae and Diaporthe fungi can infect shoots by inoculating the natural fruit abscission wounds in the field. This study generates new insights into the influence of fruit infection leading to shoot blight and branch dieback of English walnut caused by Botryosphaeriaceae and Diaporthe fungi. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa subsp. pauca (XFP), Neofusicoccum mediterraneum, N. stellenboschiana and other fungi have been found in olive groves of Salento (Apulia, Italy) that show symptoms of severe decline. XFP is well known to be the cause of olive quick decline syndrome (OQDS). It has also been assessed that Neofusicoccum spp. causes a distinct disease syndrome, namely, branch and twig dieback (BTD). All these phytopathogens incite severe symptoms that can compromise the viability of large canopy sectors or the whole tree. However, their specific symptoms are not easily distinguished, especially during the final stages of the disease when branches are definitively desiccated. By contrast, they can be differentiated during the initial phases of the infection when some facets of the diseases are typical, especially wood discoloration, incited solely by fungi. Here, we describe the typical symptomatological features of OQDS and BTD that can be observed in the field and that have been confirmed by Koch postulate experiments. Similar symptoms, caused by some abiotic adverse conditions and even by additional biotic factors, are also described. Thus, this review aims at: (i) raising the awareness that declining olive trees in Salento do not have to be linked a priori to XFP; (ii) defining the guidelines for a correct symptomatic diagnosis to orient proper laboratory analyses, which is crucial for the application of effective control measures. The possibility that bacterium and fungi could act as a polyspecies and in conjunction with predisposing abiotic stresses is also widely discussed. [ABSTRACT FROM AUTHOR]

In the light of ongoing climate change, European beech trees face a loss of vitality due to an expected increase in the frequency of droughts, exacerbated by prolonged periods of high temperatures and solar radiation. Such conditions increase the predisposition to European beech splendour beetle attacks, and trigger sunburn, fungal infections and complex diseases. As a result, European beech forests are seriously threatened by climate change. Following prolonged and repeated periods of exceptional drought since 2018, European beech decline have been observed in several regions of Germany and Europe. Vitality losses, in some cases severe, of due to the extraordinarily warm, dry summers of 2018 and 2019 have been observed and investigated in several regions of Germany. The first symptoms of vitality loss of European beech associated with severe signs of crown dieback were recorded in midsummer 2018. Mortality of branches and individual trees was often associated with sunburn, bark necrosis and bleeding spots of sap flux. The first signs of mortality were observed locally in predisposed stands in autumn 2018. The stem stability and break resistance of affected trees were significantly reduced. To elucidate the complex interactions involved, the occurrence of vitality loss of European beech and associated causative agents were examined in north-western Germany. Disease symptoms of individual trees were studied, associated fungi (endophytes, plant pathogens and saprobes) were isolated and identified. Frequent potentially severe pathogens included Neonectria coccinea, Diplodia corticola and D. mutila. The presented cases of disease were the first, where D. corticola was recorded on beech. In addition, inoculation tests were used to assess the potential roles of Botryosphaeria species in the observed symptomatology. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs) are taking the forefront of winegrowers' concerns, as they cause considerable damage in vineyards not only quantitatively but also qualitatively. Furthermore, in the last three decades, an increasing incidence of the socioeconomic impact of these fungal pathologies has been observed. To date, no effective control strategies or curative treatments are available for these diseases that can replace the effectiveness offered by a series of chemical synthesis fungicides currently prohibited by European legislation. In this scenario, screening for less sensitive cultivars is regarded as a sustainable approach for GTDs management. In the study presented herein, the tolerance/susceptibility of 25 cultivars from the Grapevine Germplasm Bank of Aragon (Movera, Zaragoza, Spain) including commercial, local, or minority germplasm, was tested against two pathogens associated with Botryosphaeria dieback (viz. Neofusicoccum parvum and Diplodia seriata), which were inoculated in a detached cutting assay under open-air conditions. Based on lesion length development after eight months, significant differences were detected among the cultivars in the length of internal (vascular) necroses. In general terms, all cultivars were susceptible to fungal infection, but 'Macabeo' and one of the 'Garnacha Tinta' ecotypes under study (from Villanueva de Huerva, Zaragoza) would be the least susceptible white and red cultivars, respectively. On the other hand, 'Monegrina', 'Grumel', and 'Torcijón' would be among the least tolerant cultivars to fungal infection. [ABSTRACT FROM AUTHOR]

A recent survey conducted in the historical botanical garden Villa Caronia, Sicily, identified the causal organisms of branch cankers and dieback on a mature Meryta denhamii. Laboratory isolations and sequencing of three loci, namely ITS, tef1-α, and tub2, showed the presence of two species belonging to Botryosphaeriaceae, including Neofusicoccum parvum and Neoscytalidium dimidiatum. Pathogenicity tests confirmed that these species are able to induce canker symptoms on this host. To our knowledge, this is the first report, worldwide, of N. parvum and Ne. dimidiatum causing branch canker and dieback on M. denhamii. [ABSTRACT FROM AUTHOR]

The San Joaquin Valley (California, USA) represents an important fig (Ficus carica) production area in the United States. Fig limb dieback represents a serious and emerging disease of fig caused by Neoscytalidium dimidiatum. In the present study we evaluated the effect of tissue age on canker development, the recovery of the fungus from fruit mummies collected in the field, the ability of N. dimidiatum to colonize, under laboratory condition, fig fruits, and the in vitro effects of different water potentials (Ψs) on mycelial growth rate.Results of our study showed that the older branches (> 3-year-old) resulted in longer canker compared to the younger ages. N. dimidiatum was not recovered from the mummies, instead they were colonized by many other fungal saprophytes. Laboratory experiments showed the ability of this species to colonize dried fig fruits from 20 °C to 35 °C. In vitro water potentials experiment showed that the mycelial growth was reduced with the decrease of water potential (from 1–3 -MPa), depending on salt type. [ABSTRACT FROM AUTHOR]

Macadamia (Macadamia integrifolia and M. tetraphylla and their hybrids) is a tree nut crop affected by Botryosphaeria branch dieback. The disease results in branch and tree death in commercial orchards, so reducing the productivity of the Australian macadamia industry. There is a dearth of knowledge of the disease cycle in macadamia, which confounds disease management. This study investigated the dynamics of pathogen inoculum associated with Botryosphaeria branch dieback and the influence of environmental factors (temperature, rainfall and relative humidity) on the seasonal spore release within the orchards. Diseased and asymptomatic plant parts from macadamia trees were collected each season for 3 years in commercial orchards. Fungal structures (pycnidia and pseudothecia) mainly were (71%) observed on symptomatic wood samples. A comparison of the number of spores released from the fungal structures between summer and autumn revealed high concentrations of Lasiodiplodia pseudotheobromae from diseased wood (4.8 × 104 conidia/cm2) and Neofusicoccum luteum from blighted leaves (2.1 × 103 conidia/cm2). The peak airborne conidia dispersal period, quantified using microscopy and quantitative PCR assays, was consistently detected after rainfall and strongly associated with relative humidity over 70% and temperatures between 20 and 27°C during summer and autumn. Botryosphaeriaceae isolates obtained from the pycnidia on the macadamia trees caused severe branch dieback symptoms when inoculated on detached macadamia twigs, which suggests both airborne and rain‐splashed spores from fungal structures on the trees contribute to the disease in macadamia orchards. [ABSTRACT FROM AUTHOR]

Grapevine Trunk Diseases (GTDs) are major threats in Mediterranean countries, causing economic losses due to reduced grape yields and long-term vine productivity, as well as death of grapevines. A survey was conducted in Piedmont (Northern Italy) during 2021-2022 to investigate the species diversity and distribution of GTD pathogens in this important Italian wine region. Morphological and multilocus phylogenetic analyses (based on ITS, tef1, tub2, act and rpb2) identified species of Botryosphaeriaceae at high frequency, including Botryosphaeria dothidea, Diplodia mutila, Diplodia seriata and Neofusicoccum parvum. Other pathogens commonly associated with GTDs, including Eutypa lata, Fomitiporia mediterranea and Phaeomoniella chlamydospora, were also isolated. Less commonly isolated species included Neocucurbitaria juglandicola, Paraconiothyrium brasiliense, Seimatosporium vitis-viniferae and Truncatella angustata. Pathogenicity tests with two representative isolates of each species were carried out using one-year-old potted grapevine cuttings (‘Barbera’). All isolates (except N. juglandicola) caused brown wood necrotic vascular discolourations on inoculated plants and were successfully re-isolated. Effects of temperature on colony growth were also assessed. For all tested isolates there was no growth at 5°C, only four isolates (Botryosphaeriaceae) grew at 35°C, and optimum growth temperatures were between 20 and 25°C. This is the first record of Paraconiothyrium brasiliense and Neocucurbitaria juglandicola associated with symptomatic grapevines in Italy. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases cause severe damage in grapevines. Management strategies focus on protection of grapevine pruning wounds using chemical fungicides or biological control agents. Botryosphaeria dieback, caused mainly by Lasiodiplodia spp., is one of the main trunk diseases in northwest Mexico. This study obtained endophytic bacteria and fungi from the heritage grapevine Vitis vinifera cv. ‘Mission’ for potential biological control of Botryosphaeria dieback. A collection of 135 bacterial and 37 fungal isolates were obtained and initially tested for antagonistic activity against Lasiodiplodia brasiliensis. The most promising isolates belonging to Trichoderma and Bacillus spp. were selected and characterized to determine their modes of action. Bacillus isolates produced volatile organic compounds that inhibited growth of Neofusicoccum parvum, and diffusible organic compounds with antifungal effects against L. brasiliensis and N. parvum. Trichoderma isolates produced diffusible organic compounds and were mycoparasites. In greenhouse assays, plants inoculated with three Trichoderma asperellum isolates (T20BCMX, EF09BCMX, and EF11BCMX), B. amyloliquefaciens (BEVP26BCMX) or Bacillus sp. (rbES015), applied preventively in soil, gave up to 50% smaller necrotic lesions when compared with the plants inoculated only with L. brasiliensis. In the field, plants inoculated with three Bacillus isolates (BEVP02BCMX, BEVP26BCMX, BEVP31BCMX) or five Trichoderma (T11BCMX, T15BCMX, T17BCMX, T20BCMX, and EF11BCMX) had lesions up to four times smaller than control plants inoculated only with L. brasiliensis. This study has demonstrated the potential of heritage grapevines to provide biological control agents for Botryosphaeria dieback. [ABSTRACT FROM AUTHOR]

Introduction: The present work identified and compared intracellular metabolites and metabolic networks in mycelial cultures of Lasiodiplodia theobromae grown under 12 natural light and 24 hours' dark using a 1 H NMR-based metabolomics approach. Materials and methods: Fungal cultures were grown in potato dextrose media, and metabolites were extracted by sonication with sodium phosphate-buffered saline (pH = 6.0, 10% D2O, 0.1 mM TSP) from mycelium samples collected every week over four weeks. Results: Multivariate analyses revealed that the light exposure group showed a positive correlation within beta-hydroxybutyrate, acetoacetate, acetone, betaine, choline, glycerol, and phosphocholine. On the other hand, phenyl acetate, leucine, isoleucine, valine, and tyrosine were positively correlated with dark conditions. Light favored the oxidative degradation of valine, leucine, and isoleucine, leading to the accumulation of choline, phosphocholine, betaine, and ketone bodies (ketogenesis). Ketogenesis, gluconeogenesis, and the biosynthesis of choline, phosphocholine, and betaine, were considered discriminatory routes for light conditions. The light-sensing pathways were interlinked with fungal development, as verified by the increased production of mycelia biomass without fruiting bodies and stress signaling, as demonstrated by the increased production of pigments. [ABSTRACT FROM AUTHOR]

Stem blight is a destructive woody disease of blueberry (Vaccinium corymbosum) caused by several species of the family Botryosphaeriaceae. A field survey was conducted in the mayor blueberry production area of Chile, comprising latitudes 32°49ʹS to 40°55ʹS, to determine the occurrence and distribution of Botryosphaeriaceae in the region. Together, a multilocus analysis, morphological characterization, and phytopathogenicity testing were used to identify 51 Neofusicoccum isolates belonging to N. nonquaesitum (28 strains), N. parvum (22 strains), and N. australe (1 strain). Of these, N. parvum and N. nonquaesitum were the most commonly found, with N. parvum most frequent from latitude 37°40ʹS to the north and N. nonquaesitum predominantly located from the same latitude toward the south. Morphological traits of the isolates were consistent with the species identified by molecular techniques, despite the overlapping of conidial size of some isolates among species. Pathogenicity trials showed that the three species were pathogenic to blueberry plants and revealed that N. parvum and N. nonquaesitum were the most aggressive species, although variability in virulence was observed among isolates of N. parvum and N. nonquaesitum. [ABSTRACT FROM AUTHOR]

Coscinium fenestratum is a medicinally significant critically endangered plant found in Western Ghats of India. The leaf spot and blight was observed in Kerala during 2021 with disease incidence of 40% in 20 assessed plants in 0.6 hectare. The associated fungus was isolated on potato dextrose agar medium. A total of six morpho-culturally identical isolates were isolated and morphologically identified. Based on morpho-cultural features, the fungus was identified at genus level as Lasiodiplodia sp. which was further authentically confirmed as Lasiodiplodia theobromae by molecular identification with a representative isolate (KFRIMCC 089) using multigene (ITS, LSU, SSU, TEF1 -α , and TUB2) sequence analysis and concatenated phylogenetic analysis (ITS-TEF1 -α -TUB2). Pathogenicity tests were also assessed in vitro and in vivo using mycelial disc and spore suspension of L. theobromae , and the isolated fungus's pathogenic behaviour was confirmed after re-isolation and morpho-cultural features. Literature survey reveals that there are no reports of L. theobromae on C. fenestratum from all over the world. Hence, C. fenestratum is being firstly reported as a new host record for L. theobromae from India. [ABSTRACT FROM AUTHOR]

Fungi belonging to the family Botryosphaeriaceae have been implicated in significant economic loss in many horticultural crops worldwide. These fungal pathogens pose an emerging risk to the productivity of the Australian walnut industry, although which species of Botryosphaeriaceae are present is unknown. To address this knowledge gap, walnut tissues were collected from 14 orchards representing the major walnut‐growing regions of Australia, and fungal isolations performed. Botryosphaeriaceae species were recovered from both symptomatic and asymptomatic samples from nine of the orchards. DNA sequencing confirmed the presence of five Botryosphaeriaceae species, namely Diplodia seriata, Dothiorella omnivora, Neofusicoccum parvum, N. macroclavatum and Spencermartinsia viticola. Of the 106 Botryosphaeriaceae isolates recovered, D. seriata and N. parvum were the most prevalent species. Pathogenicity studies using detached stems indicated that Neofusicoccum spp. were the most virulent followed by D. seriata. This is the first systematic study on the incidence, identification and pathogenicity of species of Botryosphaeriaceae from walnut orchards in Australia. [ABSTRACT FROM AUTHOR]

Increased branch canker and dieback were observed in commercial avocado (Persea americana) orchards in Sicily, Italy. Surveys were conducted in 2021 and 2022 on 11 orchards to investigate etiology of the disease. Seventy-five plants from four orchards, showing branch canker and dieback, were sampled. Isolations from woody diseased tissues revealed the presence of fungi (Botryosphaeriaceae). Identification of the isolates was achieved by morphological and multi-loci phylogenetic analyses (Maximum Parsimony and Maximum Likelihood) of the ITS, tef1-α, and tub2 loci. Botryosphaeria dothidea, Lasiodiplodia citricola, Macrophomina phaseolina, Neofusicoccum cryptoaustrale, and Neofusicoccum luteum were identified. Representative isolates collected from the orchards, characterized based on the tub2 locus and identified as N. parvum, were excluded from this study, since this species has already been reported in our territory. Pathogenicity tests were conducted on potted, asymptomatic, 2-year-old avocado trees using mycelial plugs. These tests showed that all the Botryosphaeriaceae species characterized in this study were pathogenic to avocado. This is the first report of L. citricola, M. phaseolina and N. cryptoaustrale causing canker and dieback on avocado trees, and is the first record of these fungi causing branch disease on avocado in Italy. [ABSTRACT FROM AUTHOR]

Lasiodiplodia species cause dieback, shoot blight, fruit rot, and stem-end rot of woody plants. Recently, studies on taxonomic revision of Lasiodiplodia species have been conducted globally and have led to more clarification of the species diversity of this genus. However, only three species of the genus have been reported in Japan. To evaluate the species diversity of Lasiodiplodia in Japan, we re-examined the taxonomical positions of 30 isolates based on their morphological and cultural characteristics and phylogenetic relationships. Phylogenetic analyses were performed using a matrix comprising ITS, tef1, tub2, and rpb2 sequences, and the results indicate that the examined Japanese isolates belong to six species: Lasiodiplodia brasiliensis, L. hormozganensis, L. pseudotheobromae, L. thailandica, L. theobromae, and Lasiodiplodia sp. Moreover, three of these species were newly added to the Japanese mycoflora. [ABSTRACT FROM AUTHOR]

Fungi of the family Botryosphaeriaceae are considered responsible for various symptoms in avocado such as dieback, external necrosis of branches and inflorescences, cankers on branches and trunks, or stem-end rot of fruits. In recent years, these problems are becoming more frequent in avocado orchards in the Canary Islands (Spain). This work includes the characterization of fungal species involved in these diseases, which were isolated from avocado crops in Tenerife Island between 2018 and 2022. A total of 158 vegetal samples were collected, from which 297 fungal isolates were culture-isolated. Fifty-two of them were selected according to their morphological features as representative isolates of Botryosphaeriaceae, and their molecular characterization was carried out, sequencing the ITS1-2 region as well as the β-tubulin and the elongation factor 1-alpha genes. Five species of Botryosphaeriaceae were isolated, including Neofusicoccum australe, N. cryptoaustrale/stellenboschiana, N. luteum, N. parvum, and Lasiodiplodia brasiliensis. This is the first time that L. brasiliensis has been associated with avocado dieback and that N. cryptoaustrale/stellenboschiana has been cited in avocado causing symptoms of dieback and stem-end rot. However, it was not possible to assign our isolates unequivocally to N. cryptoaustrale or N. stellenboschiana even additionally using the rpb2 marker for their molecular characterization. Botryosphaeriaceae family seem to be involved in avocado dieback, in the premature fall of fruits during their development in the field and in post-harvest damage in Tenerife, but further studies are needed to clarify the fungal pathogens associated with symptoms in relation to phenological plant growth stages or less frequently observed. [ABSTRACT FROM AUTHOR]

(1) Background: Grapevine trunk diseases (GTDs) have become a global threat to vineyards worldwide. These diseases share three main common features. First, they are caused by multiple pathogenic micro-organisms. Second, these pathogens often maintain a long latent phase, which makes any research in pathology and symptomatology challenging. Third, a consensus is raising to pinpoint combined abiotic stresses as a key factor contributing to disease symptom expression. (2) Methods: We analyzed the impact of combined abiotic stresses in grapevine cuttings artificially infected by two fungi involved in Botryosphaeria dieback (one of the major GTDs), Neofusicoccum parvum and Diplodia seriata. Fungal-infected and control plants were subjected to single or combined abiotic stresses (heat stress, drought stress or both). Disease intensity was monitored thanks to the measurement of necrosis area size. (3) Results and conclusions: Overall, our results suggest that combined stresses might have a stronger impact on disease intensity upon infection by the less virulent pathogen Diplodia seriata. This conclusion is discussed through the impact on plant physiology using metabolomic and transcriptomic analyses of leaves sampled for the different conditions. [ABSTRACT FROM AUTHOR]

Stem rot disease is a major threat to the successful cultivation of jute (Corchorus spp.). Although Macrophomina phaseolina is the causal agent attributed to this disease, in the present study we documented the involvement of several pathogens. Disease samples were collected from West Bengal, a major jute‐growing state in India and six different types of symptoms were observed under field conditions. Isolated pathogens (n = 387) produced four types of colonies resembling growth patterns of Colletotrichum, Diaporthe, Lasiodiplodia and Macrophomina. Based on pigmentation on the reverse side of plates, Diaporthe‐ and Lasiodiplodia‐type colonies formed two subgroups each. However, no correlation could be established between types of disease symptoms and the associated pathogens. While Colletotrichum was prevalent in the Coochbehar district, the spatial distribution of the other pathogens was random. Internal transcribed spacer (ITS) of rDNA and translation elongation factor 1‐α (TEF) genes from two representative isolates from each of six morphogroups were amplified and sequenced. Phylogenetic trees were generated based on these sequences, which suggested that seven fungal pathogens belonging to four genera (Colletotrichum, Diaporthe, Lasiodiplodia and Macrophomina) were involved with stem lesions of jute. Three recommended fungicides (carbendazim, hexaconazole and tebuconazole) were tested against the selected fungal pathogens and all were found effective in suppressing their growth in vitro. [ABSTRACT FROM AUTHOR]

Mitidjospirone, a new spiridioxynaphthalene, was isolated from the mycelial extract of a strain of Lasiodiplodia mitidjana, a recently described species belonging to the family Botryosphaeriaceae. Its structure was elucidated by extensive spectroscopic analysis and the absolute configuration was determined by electronic circular dichroism (ECD) experiment. Furthermore, several known compounds were identified during the screening of secondary metabolites produced by four strains of L. mitidjana. [ABSTRACT FROM AUTHOR]

The Botryosphaeriales order is best known for the diseases they cause in woody plants, as primary pathogens or latent pathogens residing in the woody tissue of asymptomatic hosts. In the first instance, Botryosphaeriales species have been identified in Venezuela using morphological descriptions in the '80s and '90s, and later, the mid-2000s using molecular techniques. The morphological descriptions of the asexual morphs were initially used for the identification of Botryosphaeriales genera and species. Lasiodiplodia spp. (as L. theobromae) was the most isolated fungus in Venezuela within the Botryosphaeriales and has been found in more than 50% of the hosts in native and non-native plants, followed by Diplodia, Dothiorella, Fusicoccum, Microdiplodia, Macrophomina, Neofusicoccum, Sphaeropsis, and Botryosphaeria, considered all of them cosmopolitan group. Molecular studies, that included DNA sequence data from multiple genes, such as the internal transcribed spacer of rDNA (ITS), translation elongation factor-1a (tef1), and ß-tubulin (btub) used on the fungi isolated from woody plants, mainly trees or forest species, reveled the presence of two families within the Botryosphaeriales order for Venezuela. Botryosphaeriaceae family includes the genera: Botryosphaeria, Cophinforma, Diplodia, Lasiodiplodia and Neofusicoccum, and the Pseudofusicoccumaceae family includes the genus Pseudofusicoccum. In the Botryosphaeriaceae the Lasiodiplodia genus was the most predominant in most hosts, and the species L. theobromae the most isolated in native and non-native plants. Botryosphaeria dothidea, Cophinforma atrovirens, Diplodia scrobiculata (syn. D. guayanensis), Lasiodiplodia brasiliensis, L. crassispora, L. pseudotheobromae, Neofusicoccum arbuti (syn. N. andinum), N. parvum, and N. ribis are cosmopolitan species, and they were isolated from native and non-native plants. Pseudofusicoccum stromaticum was found in plantations non-native of Acacia mangium, E. urophylla x E. grandis, Eucalyptus urophylla, and reported exclusively in South America. Lasiodiplodia venezuelensis has only been reported in Venezuela, and it was isolated from native and non-native plants. The presence, distribution, diversity, and symptoms of these fungi, mainly of the new genus, new species, and reports found in Venezuela and other parts of the world, were also reviewed. [ABSTRACT FROM AUTHOR]

The diagnostic survey of seedborne fungal pathogens is fundamental for symptomless material stored in gene banks to avoid the diffusion of pathogens by germplasm distribution and propagation. In this work, seeds of Southern Italian landraces of the common bean (Phaseolus vulgaris L.) belonging to the gene bank at CREA (Italy) were inspected to assess their phytosanitary status. The phytopathological analysis revealed the presence of the most common pathogens associated with common bean seeds such as Fusarium spp., Macrophomina phaseolina, Rhizoctonia solani, Colletotrichum lindemuthianum and Diaporthe/Phomopsis complex. However, new fungi able to completely inhibit seed germination were also observed. The most aggressive were isolated, and the morpho-pathological characterization, DNA sequencing and phylogenetic analysis allowed us to define the strains as Botryosphaeria dothidea CREA OF 360.4 and Diplodia mutila CREA OF 420.36. These two plant pathogens are generally associated with grapevines and other fruit trees. Pathogenicity tests were carried out along with a transmissibility test in which the transmission of the pathogens to the seedlings was proven. Host range experiments revealed the ability of these pathogens to infect crops such as pepper and melon. To our knowledge, this is the first time that B. dothidea and D. mutila were detected on the common bean. [ABSTRACT FROM AUTHOR]

The EFSA Plant Health Panel performed a pest categorisation of Lasiodiplodia pseudotheobromae, a clearly defined fungus of the family Botryosphaeriaceae, which was first described in 2008 as a cryptic species within the L. theobromae complex. The pathogen affects a wide range of woody perennial crops and ornamental plants causing root rot, damping‐off, leaf spots, twig blight, cankers, stem‐end rot, gummosis, branch dieback and pre‐ and post‐harvest fruit rots. Lasiodiplodia pseudotheobromae is present in Africa, Asia, North and South America and Oceania and has also been reported from Spain with a restricted distribution. However, there is uncertainty on the status of the pathogen worldwide and in the EU because in the past, when molecular tools (particularly multigene phylogenetic analysis) were not available, the pathogen might have been misidentified as L. theobromae. Lasiodiplodia pseudotheobromae is not included in Commission Implementing Regulation (EU) 2019/2072 and there are no interceptions in the EU. Because of the very wide host range of the pathogen, this pest categorisation focused on those hosts for which there is robust evidence that the pathogen was formally identified by a combination of morphology, pathogenicity and multilocus sequence analysis. Plants for planting, including seeds, fresh fruits and bark and wood of host plants as well as soil and other plant‐growing media are the main pathways for the further entry of the pathogen into the EU. Host availability and climate suitability factors occurring in parts of the EU are favourable for the further establishment of the pathogen. In the area of its present distribution, including Spain, the pathogen has a direct impact on cultivated hosts. multilocus measures are available to prevent the further introduction and spread of the pathogen into the EU. Lasiodiplodia pseudotheobromae satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest. [ABSTRACT FROM AUTHOR]

Three Botryosphaeriaceae species, not previously recorded on coast redwood, were detected from native redwood stands in Humboldt Co., CA during general surveys between 2014 and 2017. Pathogenicity experiments with three of these fungi, Diplodia scrobiculata, Diplodia mutila, and Dothiorella californica, were performed on 2‐year‐old redwood seedlings to fulfil Koch's postulates and prove pathogenicity. Only D. scrobiculata produced lesions significantly longer than control lesions, although they were generally smaller than those of more virulent Botryosphaeriaceae pathogens in previous studies. In a separate pathogenicity study of D. scrobiculata on younger seedlings without secondary growth, inoculations on wounded stems resulted in black lesions that were much more externally obvious than the wound inoculations on lignified stems after 90 days. However, no lesions developed on non‐wounded stems of younger seedlings. Lesion lengths caused by D. scrobiculata were consistent between the two studies. On one wound‐inoculated, non‐woody seedling, D. scrobiculata was recovered from asymptomatic stem tissue 2 cm below the inoculation site, indicating possible pathogen latency. These experiments indicate that there are more Botryosphaeriaceae fungi involved in coast redwood dieback than previously known and confirm the pathogenicity of D. scrobiculata on primary and secondary tissue of coast redwood. [ABSTRACT FROM AUTHOR]

Neofusicoccum parvum is a fungal plant pathogen of a wide range of hosts but knowledge about the virulence factors of N. parvum and host–pathogen interactions is rather limited. The molecules involved in the interaction between N. parvum and Eucalyptus are mostly unknown, so we used a multi-omics approach to understand pathogen–host interactions. We present the first comprehensive characterization of the in vitro secretome of N. parvum and a prediction of protein–protein interactions using a dry-lab non-targeted interactomics strategy. We used LC-MS to identify N. parvum protein profiles, resulting in the identification of over 400 proteins, from which 117 had a different abundance in the presence of the Eucalyptus stem. Most of the more abundant proteins under host mimicry are involved in plant cell wall degradation (targeting pectin and hemicellulose) consistent with pathogen growth on a plant host. Other proteins identified are involved in adhesion to host tissues, penetration, pathogenesis, or reactive oxygen species generation, involving ribonuclease/ribotoxin domains, putative ricin B lectins, and necrosis elicitors. The overexpression of chitosan synthesis proteins during interaction with the Eucalyptus stem reinforces the hypothesis of an infection strategy involving pathogen masking to avoid host defenses. Neofusicoccum parvum has the molecular apparatus to colonize the host but also actively feed on its living cells and induce necrosis suggesting that this species has a hemibiotrophic lifestyle. [ABSTRACT FROM AUTHOR]

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The lectotype and epitype of Neofusicoccum laricinum proposed in previous studies failed to meet the requirements of the International Code of Nomenclature for Algae, Fungi, and Plants. Here, we propose a valid lectotype and epitype for this species that meet the requirements of the Code. [ABSTRACT FROM AUTHOR]