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Ceratocystis fimbriata is an important pathogen with a wide host range that causes xylem lesions, wilt and death in different plant species. More adapted populations of C. fimbriata have probably been selected to specific hosts and high genetic and physiological variability can be found within the pathogen populations. Thus, molecular analysis and inoculation studies were performed to investigate the genetic and physiological variability of isolates of C. fimbriata complex obtained from different host species and geographic regions in Brazil. The minimum spanning tree analysis based on 14 simple‐sequence repeat (SSR) markers of C. fimbriata exhibited a clear clustering of isolates according to host, where each groups of isolates differed in at least five loci. In addition, inoculation of eight hosts with 10 isolates revealed a wide variation in aggressiveness. By assessing the length of xylem lesions caused by C. fimbriata isolates, Ficus carica was found to be the most susceptible host, followed by Mangifera indica. Only the isolates from Theobroma cacao and Carapa guianensis proved to be host specialized. Overall, the isolates tested were more aggressive to the hosts from which they were sampled. [ABSTRACT FROM AUTHOR]

Tectona grandis Linn., also known as teak, is a highly valued species with adaptability to a wide range of climatic conditions and high tolerance to soil variations, making it an attractive option for both commercial and conservation purposes. In this sense, the classification of cultivated teak genotypes is crucial for both breeding programs and conservation efforts. This study examined the relationship between traits related to damage in the stem of teak plants caused by Ceratocystis fimbriata (a soil-borne pathogen that negatively impacts the productivity of teak plantations) and the spectral reflectance of 110 diverse clones, using near-infrared spectroscopy (NIRS) data and partial least squares regression (PLSR) analysis. Cross-validation models had R2 = 0.894 (ratio of standard error of prediction to standard deviation: RPD = 3.1), R2 = 0.883 (RPD = 2.7), and R2 = 0.893 (RPD = 2.8) for predicting stem lesion area, lesion length, and severity of infection, respectively. Teak genotypes (clones) can benefit from the creation of a calibration model utilizing NIRS-generated data paired with PLSR, which can effectively screen the magnitude of damage caused by the fungus. Overall, while the study provides valuable information for teak breeding and conservation efforts, a long-term perspective would be essential to evaluate the sustainability of teak genotypes over various growth stages and under continuous pathogen pressure. [ABSTRACT FROM AUTHOR]

A set of diseases caused by fungi and oomycetes are responsible for large losses in annual world cocoa production. Managing the impact caused by these diseases is very complex because a common solution has yet to be found for different pathogens. In this context, the systematic knowledge of Theobroma cacao L. pathogens' molecular characteristics may help researchers understand the possibilities and limitations of cocoa disease management strategies. This work systematically organized and summarized the main findings of omics studies of T. cacao eukaryotic pathogens, focusing on the plant–pathogen interaction and production dynamics. Using the PRISMA protocol and a semiautomated process, we selected papers from the Scopus and Web of Science databases and collected data from the selected papers. From the initial 3169 studies, 149 were selected. The first author's affiliations were mostly from two countries, Brazil (55%) and the USA (22%). The most frequent genera were Moniliophthora (105 studies), Phytophthora (59 studies) and Ceratocystis (13 studies). The systematic review database includes papers reporting the whole-genome sequence from six cocoa pathogens and evidence of some necrosis-inducing-like proteins, which are common in T. cacao pathogen genomes. This review contributes to the knowledge about T. cacao diseases, providing an integrated discussion of T. cacao pathogens' molecular characteristics, common mechanisms of pathogenicity and how this knowledge is produced worldwide. [ABSTRACT FROM AUTHOR]

Between 2021 and 2023, a new disease affecting West Indian mahogany plants emerged in South Sumatra, Indonesia. The disease’s incidence steadily increased, particularly in Palembang (Jakabaring), where it rose from 0.27 to 0.46%, and in Bukit Siguntang, increased from 0 to 0.73%. In Ogan Ilir Regency (Universitas Sriwijaya), the incidence increased from 2.07 to 4.71%, and in Ogan Komering Ilir Regency (Celika) the incidence rose from 6.77 to 15.25%. Initial symptoms of this disease on the plant’s stem included canker formation, gum exudation, vascular tissue discoloration, leaf wilting, and eventual plant death. The fungus was isolated from symptomatic vascular tree tissue and confirmed as a pathogen following Koch’s postulates. Pathogen identification used a polyphasic approach, combining morphological and molecular characteristics from specific genomic regions (ITS and β-tubulin). Morphological traits and phylogenetic analysis identified the isolate as Ceratocystis fimbriata sensu stricto. Ceratocystis fimbriata has not been identified as the cause of cankers and wilting in West Indian mahogany trees in Indonesia, and this is the first report. Pathogenicity tests have demonstrated that the pathogen causes death in mahogany trees, as well as in Acacia, bullet wood, and jackfruit plants, indicating its potential to affect other agroforestry plants and pose a threat to the biodiversity of indigenous plants in South Sumatra, Indonesia. [ABSTRACT FROM AUTHOR]

Acacia mangium is an important wood for commercial products especially pulp and medium-density fibreboard. However, it is susceptible to Ceratocystis fimbriata infection, leading to Ceratocystis wilt. Therefore, the present work aimed to (i) establish the diversity of endophytic fungi in different plant parts of A. mangium,and (ii) evaluate the antifungal potentials of the isolated and identified endophytic fungi against C. fimbriata. Endophytic fungal identification was conducted by PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) and ITS4 regions of nuclear ribosomal DNA. A total of 66 endophytic fungi were successfully isolated from different parts of A. mangium; leaf (21), stem (13), petiole (12), root (9), flower (6), and fruit (5). The endophytic fungal isolates belonged to Ascomycota (95.5%) and Zygomycota (4.5%). For Ascomycota 13 genera were identified: Trichoderma (28.6%), Nigrospora (28.6%), Pestalotiopsis (12.7%), Lasiodiplodia (9.5%), Aspergillus (6.3%), Sordariomycetes (3%), and Neopestalotiopsis, Pseudopestalotiopsis, Eutiarosporella, Curvularia, Fusarium, Penicillium, and Hypoxylon each with a single isolate. For Zygomycota, only Blakeslea sp. (5%) was isolated. Against C. fimbriata, Trichoderma koningiopsis (AC 1S) from stem, Nigrospora oryzae (AC 7L) from leaf, Nigrospora sphaerica (AC 3F) from the flower, Lasiodiplodia sp. (AC 2 U) from fruit, Nigrospora sphaerica (AC 4P) from petiole, and Trichoderma sp. (AC 9R) from root exhibited strong inhibition for C. fimbriata between 58.33 to 69.23%. Thus, it can be concluded that certain endophytic fungi of A. mangium have the potential to be harnessed as antiCeratocystis agent in future biotechnological applications. [ABSTRACT FROM AUTHOR]

Acacia mangium is an important wood for commercial products especially pulp and medium-density fibreboard. However, it is susceptible to Ceratocystis fimbriata infection, leading to Ceratocystis wilt. Therefore, the present work aimed to (i) establish the diversity of endophytic fungi in different plant parts of A. mangium,and (ii) evaluate the antifungal potentials of the isolated and identified endophytic fungi against C. fimbriata. Endophytic fungal identification was conducted by PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) and ITS4 regions of nuclear ribosomal DNA. A total of 66 endophytic fungi were successfully isolated from different parts of A. mangium; leaf (21), stem (13), petiole (12), root (9), flower (6), and fruit (5). The endophytic fungal isolates belonged to Ascomycota (95.5%) and Zygomycota (4.5%). For Ascomycota 13 genera were identified: Trichoderma (28.6%), Nigrospora (28.6%), Pestalotiopsis (12.7%), Lasiodiplodia (9.5%), Aspergillus (6.3%), Sordariomycetes (3%), and Neopestalotiopsis, Pseudopestalotiopsis, Eutiarosporella, Curvularia, Fusarium, Penicillium, and Hypoxylon each with a single isolate. For Zygomycota, only Blakeslea sp. (5%) was isolated. Against C. fimbriata, Trichoderma koningiopsis (AC 1S) from stem, Nigrospora oryzae (AC 7L) from leaf, Nigrospora sphaerica (AC 3F) from the flower, Lasiodiplodia sp. (AC 2 U) from fruit, Nigrospora sphaerica (AC 4P) from petiole, and Trichoderma sp. (AC 9R) from root exhibited strong inhibition for C. fimbriata between 58.33 to 69.23%. Thus, it can be concluded that certain endophytic fungi of A. mangium have the potential to be harnessed as anti-Ceratocystis agent in future biotechnological applications.

Tectona grandis Linn., also known as teak, is a highly valued species with adaptability to a wide range of climatic conditions and high tolerance to soil variations, making it an attractive option for both commercial and conservation purposes. In this sense, the classification of cultivated teak genotypes is crucial for both breeding programs and conservation efforts. This study examined the relationship between traits related to damage in the stem of teak plants caused by Ceratocystis fimbriata (a soil-borne pathogen that negatively impacts the productivity of teak plantations) and the spectral reflectance of 110 diverse clones, using near-infrared spectroscopy (NIRS) data and partial least squares regression (PLSR) analysis. Cross-validation models had R2 = 0.894 (ratio of standard error of prediction to standard deviation: RPD = 3.1), R2 = 0.883 (RPD = 2.7), and R2 = 0.893 (RPD = 2.8) for predicting stem lesion area, lesion length, and severity of infection, respectively. Teak genotypes (clones) can benefit from the creation of a calibration model utilizing NIRS-generated data paired with PLSR, which can effectively screen the magnitude of damage caused by the fungus. Overall, while the study provides valuable information for teak breeding and conservation efforts, a long-term perspective would be essential to evaluate the sustainability of teak genotypes over various growth stages and under continuous pathogen pressure.

A set of diseases caused by fungi and oomycetes are responsible for large losses in annual world cocoa production. Managing the impact caused by these diseases is very complex because a common solution has yet to be found for different pathogens. In this context, the systematic knowledge of Theobroma cacao L. pathogens’ molecular characteristics may help researchers understand the possibilities and limitations of cocoa disease management strategies. This work systematically organized and summarized the main findings of omics studies of T. cacao eukaryotic pathogens, focusing on the plant–pathogen interaction and production dynamics. Using the PRISMA protocol and a semiautomated process, we selected papers from the Scopus and Web of Science databases and collected data from the selected papers. From the initial 3169 studies, 149 were selected. The first author’s affiliations were mostly from two countries, Brazil (55%) and the USA (22%). The most frequent genera were Moniliophthora (105 studies), Phytophthora (59 studies) and Ceratocystis (13 studies). The systematic review database includes papers reporting the whole-genome sequence from six cocoa pathogens and evidence of some necrosis-inducing-like proteins, which are common in T. cacao pathogen genomes. This review contributes to the knowledge about T. cacao diseases, providing an integrated discussion of T. cacao pathogens’ molecular characteristics, common mechanisms of pathogenicity and how this knowledge is produced worldwide.

Main conclusion: Decreased accumulation of polyphenol oxidase, H2O2 accumulation, effective regulation of programmed cell death, and a protein predicted as allergenic can play key roles in cacao defense against Ceratocystis cacaofunesta. Ceratocystis wilt, caused by the fungus Ceratocystis cacaofunesta, has destroyed millions of Theobroma cacao trees in several countries of the Americas. Through proteomics, systems biology, and enzymatic analyses of infected stems, it was possible to infer mechanisms used by resistant (TSH1188) and susceptible (CCN51) cacao genotypes during infection. Protein extraction from xylem-enriched tissue of stems inoculated with the fungus and their controls 1 day after inoculation was carried out, followed by separation through two-dimensional gel electrophoresis and identification by mass spectrometry. Enzyme activity was determined at 1, 3, 7 and 15 days after inoculation. A total of 50 differentially accumulated distinct proteins were identified in the treatments of both genotypes and were classified into 10 different categories. An interaction network between homologous proteins from Arabidospsis thaliana was generated for each genotype, using the STRING database and Cytoscape software. Primary metabolism processes were apparently repressed in both genotypes. The resistance factors suggested for genotype TSH1188 were: H2O2 accumulation, effective regulation of programmed cell death, production of phytoalexins derived from tryptophan and furanocoumarins, and participation of a predicted allergenic protein with probable ribonuclease function inhibiting the germination and propagation of the fungus. In the susceptible genotype, it is possible that its recognition and signaling mechanism through proteins from the SEC14 family is easily overcome by the pathogen. Our results will help to better understand the interaction between cacao and one of its most aggressive pathogens, to create disease control strategies. [ABSTRACT FROM AUTHOR]

Ceratocystis wilt of yerba mate (Ilex paraguariensis) caused by the fungus Ceratocystis fimbriata was observed in 2018 in commercial plantations located in São Mateus do Sul, PR and Arvorezinha, RS, Brazil, where mortality of the plants was up to 5%. Due to the need of control measures for this disease and to the lack of knowledge on the impact of this pathogen this new host, this study aimed to evaluate the aggressiveness of C. fimbriata isolates collected from yerba mate plantations and screen for host responses in yerba mate clones to Ceratocystis wilt. Two experiments were conducted in a completely randomized design, with 11 treatments (isolates) to assess aggressiveness of the isolates. Two experiments were conducted to assess resistance of yerba mate to C. fimbriata in a completely randomized design in a 6 × 2 factorial scheme (6 clones × 2 isolates) in two different environmental conditions (plant growth chamber and greenhouse). The isolates of C. fimbriata showed different levels of aggressiveness to yerba mate, and all evaluated clones were susceptible to Ceratocystis wilt. The plant growth chamber condition led to a faster death of the plants compared with greenhouse. This information will be useful to understand the pathosystem and seek strategies for controlling this disease in yerba mate. [ABSTRACT FROM AUTHOR]

Key message: A histopathological study using one resistant and one susceptible clone ofEucalyptus urophylla × Eucalyptus grandishybrid showed that the colonization ofCeratocystis fimbriatawas limited by rapid and intense host defense responses such as closure of the vessel pits; formation of tyloses and gels; accumulation of amorphous material, starch, phenolic compounds, and calcium oxalate; and tissue lignification. The defense mechanisms of the resistant clone were not lethal to the pathogen because the fungus was reisolated from the diseased tissue. Context: The use of resistant genotypes of eucalypt is widely used to control Ceratocystis wilt caused by Ceratocystis fimbriata. However, little is known regarding the fungal infection process and the host defense responses. Aims: Thus, the objectives of this study were to compare the histopathological responses of one resistant and one susceptible clone of Eucalyptus urophylla × Eucalyptus grandis to artificial inoculation with C. fimbriata and to identify possible host defense responses against fungal infection. Methods: Fungal colonization was analyzed by light and scanning electron microscopy. The host defense responses to artificial fungal inoculation were evaluated through histochemical analysis and determining of the lignin concentration and lesion lengths, whereas the pathogen viability was confirmed by reisolations. Results: Both tested clones showed similar responses against fungal infection but presented defense responses with different speeds and intensities. Fungal colonization was not restricted in the tissue of plants from the susceptible clone, whereas in the resistant clone, fungal colonization was limited to the xylem vessels and parenchyma around the vessels due to closure of the vessel pits; intense formation of tyloses and gels; accumulation of amorphous material, starch, phenolic compounds, and calcium oxalate; and tissue lignification. However, the fungus was reisolated from the inoculated tissues of both clones. Conclusion: The resistance of eucalypt cuttings was found to be based on the rapid and intense defense responses shaped by biochemical and structural mechanisms that contained fungal colonization in the xylem vessels and parenchyma tissues. [ABSTRACT FROM AUTHOR]

The overall goal of this study was to determine whether the genome of an important plant pathogen in Africa, Ceratocystis albifundus , is structured into subgenomic compartments, and if so, to establish how these compartments are distributed across the genome. For this purpose, the publicly available genome of C. albifundus was complemented with the genome sequences for four additional isolates using the Illumina HiSeq platform. In addition, a reference genome for one of the individuals was assembled using both PacBio and Illumina HiSeq technologies. Our results showed a high degree of synteny between the five genomes, although several regions lacked detectable long-range synteny. These regions were associated with the presence of accessory genes, lower genetic similarity, variation in read-map depth, as well as transposable elements and genes associated with host-pathogen interactions (e.g. effectors and CAZymes). Such patterns are regarded as hallmarks of accelerated evolution, particularly of accessory subgenomic compartments in fungal pathogens. Our findings thus showed that the genome of C. albifundus is made-up of core and accessory subgenomic compartments, which is an important step towards characterizing its pangenome. This study also highlights the value of comparative genomics for understanding mechanisms that may underly and influence the biology and evolution of pathogens. • Ceratocystis albifundus has a two-speed genome. • Its genome consists of core and accessory subgenomic compartments. • Genetic variation is linked to the presence and activity of transposable elements. • Genome structure likely contributed to pathogenicity and host specialization. [ABSTRACT FROM AUTHOR]

In Indonesia,Acacia mangiumplantations exceed 1.6 Mha contributing approximately 3.5% of the country’s GDP. The viability of these plantations is increasingly threatened by fungal pathogens, insect pests, squirrels, monkeys, elephants and wind damage. Studies indicate that the problem is growing and in some areas, fungal pathogens such asGanodermaandCeratocystisspecies have contributed up to 50% tree mortality by the fourth rotation. Multiple statistical procedures were employed to examine the influence of soil and topographical properties on tree survival (trees ha−1), wood production (m3ha−1), and mortality associated with Ganoderma root rot, Ceratocystis wilt and by wind. Soil family level was found to be a good indicator of tree mortality. Plots with fine-loamy Typic Kandiudult soils had the highest tree survival and mortality associated with species ofGanodermaandCeratocystis, but had the lowest incidence of mortality by wind. The degree of association between soil and topographic variables with tree survival, wood production and the cause of mortality were poor and inconsistent. Tree survival was slightly higher on upslope areas away from valley bottoms, and drier mid-slopes, ridges and hilltops, and very low pH (<3.3) soils. Wood production was also slightly higher in drier, elevated locations, away from valley bottoms. Mortality by wind was slightly higher in moist, poorly drained, low-lying valley bottoms and topographically flat areas. Our ability to further pinpoint the influence of topography and soil attributes on wood production and cause of mortality was greatly compromised by the lack of site-specific soil data, and potential misclassification of the cause of mortality. This study could not reliably or consistently relate tree survival, wood production or the cause of mortality to any one, or combination of, soil and topographic variables. [ABSTRACT FROM AUTHOR]

Ceratocystis wilt, caused by Ceratocystis fimbriata, is currently one of the most important disease in eucalypt plantations. Plants infected by C. fimbriata have lower volumetric growth, lower pulp yields and reduced timber values. The physiological bases of infection induced by this pathogen in eucalypt plant are not known. Therefore, this study aims to assess the physiological and metabolic changes in eucalypt clones that are resistant and susceptible to C. fimbriata . Once, we evaluated in detail their leaf gas exchange, chlorophyll a fluorescence, water potential, metabolite profiling and growth-related parameters. When inoculated, the susceptible clone displayed reduced water potential, CO 2 assimilation rate, stomatal conductance, transpiration rate, photochemical quenching coefficient, electron transport rate, and root biomass. Inoculated resistant and susceptible clones both presented higher respiration rates than healthy plants. Many compounds of primary and secondary metabolism were significantly altered after fungal infection in both clones. These results suggest that, C. fimbriata interferes in the primary and secondary metabolism of plants that may be linked to the induction of defense mechanisms and that, due to water restrictions caused by the fungus in susceptible plants, there is a partial closure of the stomata to prevent water loss and a consequent reduction in photosynthesis and the transpiration rate, which in turn, leads to a decrease in the plant's growth-related. These results combined, allowed for a better understanding of the physiological and metabolic changes following the infectious process of C. fimbriata , which limit eucalypt plant growth. [ABSTRACT FROM AUTHOR]

Ceratocystis fimbriata is native to Brazil, where it is able to cause serious diseases on numerous hosts, especially on non-native plants. Because C. fimbriata is soilborne and not wind dispersed, highly differentiated populations are found in different regions of Brazil. The present study compared populations of C. fimbriata on taro, mango, eucalyptus and kiwifruit from the coastal Mata Atlântica region with native populations of the fungus from the Cerrado-transition region in Brazil by using 14 SSR markers and DNA sequences of ITS and mating type genes. Microsatellite and phylogenetic analyses were performed to test the hypothesis that populations on different hosts from the Mata Atlântica region are related to each other and are native to the region. The ITS sequences varied greatly among the taro isolates, with six sequences identified, from which two had not been previously reported. For mating type genes, four sequences were identified among the isolates on taro, mango, eucalyptus and kiwifruit. Phylogenetic analyses showed that Mata Atlântica populations formed a monophyletic group distinct from Cerrado-transition region populations, although earlier studies had shown that isolates from the two regions are interfertile and are considered as a single biological species. Microsatellite analysis revealed low gene diversity for each of the three Mata Atlântica populations on taro, mango and kiwifruit, suggesting that these populations had gone through genetic bottlenecks, probably by dispersal of select genotypes in vegetative propagation material. Also, microsatellite markers showed that two microsatellite genotypes from taro are widely spread in Brazil, probably by infected corms. [ABSTRACT FROM AUTHOR]

Mango is amongst the most exported fruits worldwide and the mango tree has been cultivated in many countries with tropical and subtropical climates. Currently, Ceratocystis wilt caused by Ceratocystis fimbriata is among the most important diseases on mango tree. Planting of resistant genotypes is the best strategy for disease control. In the selection of resistant plants a highly aggressive isolate should be used in inoculations under controlled conditions. Thus, the objective of this study was to evaluate whether there are differences in aggressiveness among isolates of C. fimbriata obtained from diseased mango trees in Brazil. Before inoculation, five randomly selected isolates were tested for sporulation and mycelial growth in different culture media in order to select the best conditions for inoculum production. Twenty-four isolates from the States of São Paulo, Rio de Janeiro, Minas Gerais and Mato Grosso do Sul were inoculated in the susceptible mango cultivar Espada. Subsequently, the four most aggressive isolates were inoculated in other five different mango cultivars. The culture media MEA provided the best levels of sporulation and mycelial growth for four of the five tested isolates. Isolates SEMG1-1 from Minas Gerais and SESP8-3 from São Paulo were the most aggressive. The response of cultivars to the most aggressive isolates tested in the present work varied from highly resistant to highly susceptible, 'Ubá' being the most resistant regardless of the isolate tested. These results demonstrate that there are significant differences in aggressiveness among C. fimbriata isolates from mango in Brazil, as well as cultivar × isolate interaction. [ABSTRACT FROM AUTHOR]

Ceratocystis fimbriatacauses wilt and death of plants in several important crops and native vegetation in Brazil. Ceratocystis wilt was recently found to be causing substantial mortality in kiwifruit (Actinidia deliciosaandA. chinensis) in the Farroupilha region of Rio Grande do Sul. The aim of this study was to describe the symptomatology of the new disease and characterise isolates ofC. fimbriataobtained from kiwifruit plants. Affected plants showed substantial discoloration of the woody xylem and wilt-type symptoms of the foliage, with eventual death of the whole plant. Phylogenetic analysis of ITS rDNA of 39 isolates from kiwifruit identified five haplotypes, which were placed in the Latin American clade ofC. fimbriata. The ITS haplotypes were morphologically similar to isolates ofC. fimbriatafrom other hosts in Brazil. Eight isolates of four ITS haplotypes varied somewhat in aggressiveness to three kiwifruit cultivars (Monty, Hayward and Elmwood), but all isolates were pathogenic and all three cultivars were susceptible. [ABSTRACT FROM AUTHOR]

The genomes of Ceratocystis eucalypticola, Chrysoporthe cubensis, Chrysoporthe deuterocubensis, Davidsoniella virescens, Fusarium temperatum, Graphilbum fragrans, Penicillium nordicum and Thielaviopsis musarum are presented in this genome announcement. These seven genomes are from plant pathogens and otherwise economically important fungal species. The genome sizes range from 28 Mb in the case of T. musarum to 45 Mb for Fusarium temperatum. These genomes include the first reports of genomes for the genera Davidsoniella, Graphilbum and Thielaviopsis. The availability of these genome data will provide opportunities to resolve longstanding questions regarding the taxonomy of species in these genera. In addition these genome sequences through comparative studies with closely related organisms will increase our understanding of how these pathogens cause disease. [ABSTRACT FROM AUTHOR]

Species in the North American clade (NAC) of the Ceratocystis fimbriata complex are mostly weak pathogens that infect native tree hosts through fresh wounds. Isolations from discolored tissue of wounded Tilia americana (basswood) in Iowa and Nebraska yielded a Ceratocystis species that was similar to but distinct from isolates of C. variospora from other hosts. Sequences of 28S rDNA showed that isolates from basswood did not differ from C. variospora, but there were minor differences in ITS rDNA sequences. The DNA sequences of a portion of the Cerato-platanin gene and TEF1α showed the basswood fungus to be a unique lineage. Cross inoculations in two experiments showed that the basswood isolates and C. variospora isolates from Quercus spp. were most aggressive to their respective hosts. Isolates from basswood grew slower and were less pigmented than C. variospora isolates from Quercus spp. The basswood fungus thus is distinguished from C. variospora based on phylogenetic analyses and phenotype and is herein described as C. tiliae sp. nov. [ABSTRACT FROM AUTHOR]

Theobroma cacao L., the chocolate tree, is an important tropical tree-crop that provides sustainable economic and environmental benefits to some of the poorest and most ecologically sensitive areas of the world. Ceratocystis wilt (CW), caused by the fungus Ceratocystis cacaofunesta, is a highly dangerous disease capable of killing the cacao plant. Histopathological studies of the host-pathogen interaction are an effective resource to study pathogenesis which will ultimately lead to a better elucidation of the mechanisms of host resistance. We analyzed the development of C. cacaofunesta reproductive structures, the pattern of fungal colonization and the anatomical responses of cacao resistant (TSH 1188) and susceptible (CCN 51) genotypes to CW. Results showed that conidia germination started within 4 h after inoculation (hai) in agar, by 12 hai conidia germination was 80 %. The resistant genotype showed little or no fungal colonization compared to the susceptible genotype. Host reactions were characterized by greater quantities of gels, gums and tyloses in the susceptible genotypes compared to the resistant. The susceptible genotype had a large number of cells surrounding the xylem vessels that were infused with dark brown phenolic compounds. The host defense reaction observed near the xylem in the resistant genotype, suggest that a mechanism involved with resistance to C. cacaofunesta. [ABSTRACT FROM AUTHOR]

Ceratocystis cacaofunesta is an ascomycete responsible for the lethal wilt disease of cacao ( Theobroma cacao L.). Marker-assisted selection combined with conventional breeding is one powerful approach to improve cacao resistance to Ceratocystis wilt. In this study we screened a set of ESTs obtained from cacao elicited with C. cacaofunesta to identify EST-SSRs and test their efficacy for mapping. Among the 3,432 ESTs analysed, 384 contained SSRs and 428 EST-SSRs were identified, mainly dinucleotides (78.5 %), with four repeats (75.23 %), and preferentially AG/CT motif (25.47 %). Gene ontology function was assigned to the ESTs containing SSRs: 4.04 % belonged to 'defense response' category, with 20.69 % of them to the sub-category 'defense response to fungi'. In relation to the ORF, the same quantity of EST-SSRs was observed in the 5′ UTR, ORF and the 3′ UTR (about 30 %). From the 428 EST-SSRs identified, 12 were polymorphic, revealing a total of 41 alleles. The number of alleles per locus ranged from 2 to 6, with an average of 3.41. Four EST-SSRs were mapped on the F Sca 6 × ICS 1 population segregating for Ceratocystis wilt, and were distributed on the 2, 3, 4 and 8 linkage groups. These markers will have potential applications in linkage mapping and will be valuable for the research community to improve the cacao breeding program. [ABSTRACT FROM AUTHOR]

Mating studies showed that isolates of the insect-associated wilt pathogen Ceratocystis fimbriata from Eucalyptus spp., mango, fig, inhame ( Colocasia esculenta), Gmelina arborea and sweet potato were interfertile, and progeny from those crosses showed normal segregation for microsatellite markers. Genetic diversity was compared among 13 populations of C. fimbriata collected from six states in Brazil using 15 highly polymorphic microsatellite markers. The gene diversity values of most eucalyptus and mango populations from Minas Gerais, Bahia, Rio de Janeiro and São Paulo states were similar to putatively native populations of Ceratocystis platani and C. cacaofunesta, two other species in the C. fimbriata complex that are homothallic. Index of association values indicated substantial asexual reproduction or selfing in populations on mango and eucalyptus. Most of these eucalyptus and mango populations were not highly differentiated from each other, and these populations and genotypes appeared to be more closely related to each other than to other populations byupgma analyses. By contrast, the G. arborea population from Pará and the fig and inhame populations from São Paulo had relatively low levels of diversity and were highly differentiated from each other and all other studied populations, suggesting that they were from different origins and had gone through genetic bottlenecks. One of the eucalyptus populations in Bahia consisted of a single genotype and may have been introduced to the site in infected cuttings from another Bahia location. Similarly, a mango population from Mato Grosso do Sul consisted of a single genotype, which was identical to one of the genotypes found on mango in São Paulo. Aside from introductions by humans, mating studies and genetic analyses suggest that limited dispersal distance and a high degree of selfing or asexual reproduction lead to local populations of C. fimbriata that have limited diversity but are highly differentiated from other populations. [ABSTRACT FROM AUTHOR]

The genus Ceratocystis contains several significant plant pathogens, causing wilt and canker disease on a wide range of plant species. There are >40 known species of Ceratocystis , some of which are becoming increasingly important in agricultural or natural ecosystems. The diagnostic procedures for most Ceratocystis species rely on time-consuming and labor-intensive culturing approaches. To provide more time-efficient and sensitive molecular diagnostic tools for Ceratocystis , a generic TaqMan real-time PCR assay was developed using the ITS gene. This novel two-probe TaqMan assay amplified DNA from all tested Ceratocystis species. Some nonspecific amplification of a few species from closely related genera was observed under certain conditions; however, these false-positive detections could be ruled out using the additional PCR primers developed for further sequence-based identification of the detected species. The assay was found to be highly sensitive, as it detected 0.2 pg/μl of Ceratocystis DNA in water as well as in host DNA matrix. Further validation with artificially inoculated fig stem tissue demonstrated that the assay was also able to effectively detect the pathogen in infected asymptomatic stem tissue. This newly developed real-time PCR assay has practical applications in biosecurity, conservation, and agriculture; it will enable the detection of Ceratocystis species directly from plant material to facilitate more sensitive screening of imported plant germplasm, and allow rapid tracking of pathogens in the case of disease outbreaks.

Ceratocystis wilt is a lethal disease of cacao, and the search for resistant genotypes may provide the best way to deal with the disease. Resistance or susceptibility behavior of some cacao genotypes when infected by Ceratocystis cacaofunesta is not yet understood. Herein, we report an LC-MS metabolomic screening analysis based on high-resolution MS to obtain comprehensive metabolic profile associated with multivariate data analysis of PLS-DA, which was effective to classify CCN-51 and TSH-1188 as resistant genotypes to C. cacaofunesta fungus, while CEPEC2002 was classified as a susceptible one. Using reversed-phase LC method, electrospray interface, and high-resolution tandem MS by the quadrupole-TOF analyzer, the typical profiles of metabolites, such as phenylpropanoids, flavonoids, lipids, alkaloids, and amino acids, were obtained. Untargeted metabolite profiles were used to construct discriminant analysis by partial least squares (PLS-DA)-derived loading plots, which placed the cacao genotypes into two major clusters related to susceptible or resistant groups. Linolenic, linoleic, oleic, stearic, arachidonic, and asiatic acids were annotated metabolites of infected, susceptible, and resistant genotypes, while methyl jasmonate, jasmonic acid, hydroxylated jasmonic acid, caffeine, and theobromine were annotated as constituents of the resistant genotypes. Trends of these typical metabolites levels revealed that CCN51 is susceptible, CEPEC2002 is moderately susceptible, and TSH1188 is resistant to C. cacaofunesta. Therefore, profiles of major metabolites as screened by LC-MS offer an efficient tool to reveal the level of resistance of cacao genotypes to C. cacaofunesta present in any farm around the world., (© 2021 Wiley-VCH GmbH.)

Mango sudden decline (MSD) caused by Ceratocystis fimbriata is one of the major diseases affecting mango crop in Brazil, Oman, and Pakistan. In Brazil, the main strategy for MSD management has been the use of resistant plants as rootstock for grafting. In this study, we tested the resistance of mango cultivar Ubá to C. fimbriata isolates from different populations. Firstly, we inoculated 2173 seedlings from 129 accessions of mango cv. Ubá using three representative fungal isolates from Brazil. Following the inoculation, the potential resistant plants were challenged against ten C. fimbriata isolates from Brazil and three from Oman. Finally, to confirm its resistance, clonal replicates of the resistant accessions were re-inoculated with the same fungal isolates. In the first selection, 13 accessions were pre-selected as resistant. In subsequent selections, they proved to be resistant to C. fimbriata isolates from populations from Oman/Pakistan and Southeastern Brazil. However, all 13 accessions were susceptible to fungal isolates from populations from Northeastern Brazil and Rio de Janeiro (also in Brazil). Our results reveal that mango cv. Ubá resistance to MSD is isolate specific and depends on the pathogen population. We obtained 13 mango cv. Ubá clones resistant to C. fimbriata , which may be useful as rootstock to MSD management in Oman and specific regions from Brazil. • The resistance of mango cultivar Ubá to mango sudden decline (MSD) is isolate specific. • Thirteen clones of mango cv. Ubá resistant to MSD were obtained. • The resistant clones may be used as rootstock in commercial orchards of mango. [ABSTRACT FROM AUTHOR]

The genetic resistance strategy is seen as the most efficient alternative for disease control. The study aimed to determine the response to infection with Ceratocystis fimbriata in cocoa clones. An artificial inoculation experiment in a CRD with a Ceratocystis fimbriata isolate and selected for virulence, was established in 21 cocoa clonal materials (F55-1, SCA 6, SCA 9, SCA 12, SCC 61, ICA 219, CAU 37, BMI 67, ICS 1, ICS 40, ICS 60, ICS 95, EET 8, CCN 51, TSH 812, UF 667, R 2, R 13, PA 46, PA 150, PA 159) Clones CCN51 and SCA 12 were used as a susceptible and resistance control, respectively. The plants were inoculated by wounding the stem 2 cm in length and 5 cm from the graft, with an inoculum of 30 μl (3x105 CFU ml-1). Plants inoculated with sterile distilled water were used as controls, 15 replicates per treatment. Weekly count readings and removal of dead plants were carried out. The final severity in the surviving plants was determined at 60 days after inoculation (DDI) as the length (mm) of the internal necrosis of the tissue from the root neck and along the stem and calculated as a severity ratio = total length of necrosis / total length of the plant. The data were examined by ANOVA, the differences between isolates established by LDS -- Fisher test (P ≥ 0.05). Clone SCA12 was considered the most tolerant, followed by clones PA 150, PA 169 and R2, all statistically similar (P ≥ 0.05) and different from clone F 55-1 qualified as the most susceptible. [ABSTRACT FROM AUTHOR]

Ceratocystis wilt is one of the main diseases of the cocoa crop, genetic resistance is the most efficient control strategy; therefore, the priority is to develop rapid methodologies to detect resistance sources. The study objective was to standardize an infection method to detect tolerance against Ceratocystis spp. An experiment for artificial inoculation of IMC 67 plants was established in a CRD. Two concentrations of inoculum were evaluated (3x105 and 3x106 CFU / ml) and three depths of wound to the stem (superficial: very fine cut maximum depth to the bark; middle: wound to the log; and deep: the wound reaches the medulla). The plants were inoculated by wounding the stem of approximately 2 cm in length and at 5 cm from the graft, 30 μl of the concentrations evaluated were used per plant. Plants inoculated with sterile distilled water were used as absolute control. Fifteen replicates per treatment were established. Weekly count readings and removal of dead plants were carried out. The final severity in the surviving plants was determined at 60 days after inoculation (DDI) as the length (mm) of the internal necrosis of the tissue from the root neck and along the stem and calculated as a severity ratio = total length of necrosis / total length of the plant. The data were examined by analysis of variance (ANAVA), the differences between treatments established by comparison of means using the LDS -- Fisher test (P ≥ 0.05). It was determined that the inoculum concentration 3x105 CFU / ml and the intermediate wound to the stem allow a higher qualification of tolerance in cocoa clones. Differences were established in the virulence of the isolates. [ABSTRACT FROM AUTHOR]

The article focuses on report of Ceratocystis fimbriata causing dieback in Conocarpus lancifolius. It mentions isolate was identified as Ceratocystis fimbriata on the basis of cultural morphology including colony pigmentation, spore shape, structure and formation of perithecium. It also mentions Ceratocystis fimbriata causes blight, wilt, dieback, decline and canker of cacao, citrus, eucalyptus, loquat, plane, pomegranate, shisham and several other important timber and fruit tree species.

• Ceratocystis fimbriata LPF1912 has a compact genome with 43% as coding sequencing. • A set of 4919 orthologous gene clusters represent the minimum quorum for the three pathogens. • Two Ceratocystis pathogens showed a different pathogenicity-related genes compared to Calonectria pseudoreteaudii. • The most of DEGs of C. fimbriata LPF1912 is related to its pathogenicity in Eucalyptus spp. Ceratocystis fimbriata is an important plant pathogen known to cause Ceratocystis Wilt (CW), a prevalent fungal disease known to affect Eucalyptus spp. plantations in Brazil. To better understand the molecular mechanisms related to pathogenicity in eucalyptus, we generated a high-quality assembly and annotation of the Ce. fimbriata LPF1912 isolate (LPF1912) genome, as well as the first transcriptome of LPF1912 from 16 eucalyptus clones at three infection incubation periods (12, 18, and 24 h). The LPF1912 genome assembly contains 805 scaffolds, totaling 31.8 Mb, with 43% of the genome estimated to be coding sequence comprised of 7,390 protein-coding genes of which 626 (8.5%) were classified as secreted proteins, 120 ribosomal RNAs, and 532 transfer RNAs. Comparative genomic analysis among three eucalyptus fungal pathogens (Ce. fimbriata, Ce. eucalypticola , and Calonectria pseudoreteaudii), showed high similarity in the proteome (21.81%) and secretome (52.01%) of LPF1912 and Ce. eucalypticola. GO annotation of pathogenicity-related genes of LPF1912 and Ce. eucalypticola, revealed enrichment in cell wall degrading enzymes (CWDEs), and lipid/cutin metabolism for Ca. pseudoreteaudii. Additionally, a transcriptome analysis between resistant and susceptible eucalyptus clones to CW infection indicated that a majority (11) of LPF1912 differentially expressed genes had GO terms associated with enzymatic functions, such as the polygalacturonase gene family, confirming the crucial role of CWDEs for Ce. fimbriata pathogenicity. Finally, our genomic and transcriptomic analysis approach provides a better understanding of the mechanisms involved in Ce. fimbriata pathogenesis, as well as a framework for further studies. [ABSTRACT FROM AUTHOR]

The genomes of Ceratocystis eucalypticola, Chrysoporthe cubensis, Chrysoporthe deuterocubensis, Davidsoniella virescens, Fusarium temperatum, Graphilbum fragrans, Penicillium nordicum and Thielaviopsis musarum are presented in this genome announcement. These seven genomes are from plant pathogens and otherwise economically important fungal species. The genome sizes range from 28 Mb in the case of T. musarum to 45 Mb for Fusarium temperatum. These genomes include the first reports of genomes for the genera Davidsoniella, Graphilbum and Thielaviopsis. The availability of these genome data will provide opportunities to resolve longstanding questions regarding the taxonomy of species in these genera. In addition these genome sequences through comparative studies with closely related organisms will increase our understanding of how these pathogens cause disease.