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The emergence of new plant diseases is an increasingly important concern. Climate change is likely to be among the factors causing most of the emerging diseases endangering forest and tree heritage around the world. Such diseases may be caused by latent pathogens or microorganisms cryptically associated with plants. The shift from a non-pathogenic to a pathogenic stage may depend on physiological alterations of the host, environmental changes, and/or stress factors. In some woods of the Salento Peninsula (Apulia Region, Italy), sudden declines of holm oak plants (Quercus ilex L.) have been observed since 2016. The morphological and molecular characterization of representative fungal isolates associated with cankers and necrosis in declining plants indicated that these isolates belong to the Botryosphaeriaceae family, and the most frequent species were Diplodia corticola and Diplodia quercivora, followed by Neofusicoccum vitifusiforme. In artificially inoculated young holm oak plants, both D. corticola and D. quercivora species produced intense and severe subcortical and leaf margin necrosis. N. vitifusiforme, although less aggressive, induced the same symptoms. Our research, in addition to confirming the involvement of D. corticola in olm oak decline, represents the first report of D. quercivora as a new pathogen of Q. ilex in Italy. Furthermore, to the best of our knowledge, we also found N. vitifusiforme as a new pathogen of Q. ilex. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

Extensive collar rot, sunken and bleeding cankers, shoot blight, and fruit rot symptoms on olive trees have recently been observed in several orchards in Italy. Since there is little information about the etiology of these diseases and given the high economic relevance of this iconic crop, a study was conducted from autumn 2017 to summer 2022, in four Italian regions, to define the occurrence, distribution and impact of the main pathogens involved. A total of 1064 symptomatic olive samples were collected and processed. Based on colony appearance, micromorphological analysis and DNA sequence data, thirty-eight species, including eighteen Botryosphaeriaceae species belonging to five genera and fifteen Phytophthora species, were isolated and identified, thirteen of which, Diplodia africana, D. fraxini, D. subglobosa, Dothiorella omnivora, Do. sarmentorum, Do. sempervirentis, Sardiniella urbana (Botryosphaeriaceae), Phytophthora cactorum, P. cinnamomi, P. citricola, P. crassamura, P. niederhauserii and P. pseudocryptogea, are reported here for the first time in olive trees. Pathogenicity tests performed on unripe drupes and on potted olive seedlings completed Koch postulates and highlighted that several species of Botryosphaeriaceae and Phytophthora represent a growing threat to olive trees. [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]

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]

In recent years, the cultivation of tropical fruit crops has increased in the Mediterranean basin, especially in southern Italy. In surveys conducted from 2014 to 2019 woody canker and shoot blight were observed on mango plants (cvs. Kent, Keitt, Sensation, Osteen, and Kensington Pride) and litchi plants (cvs. Way Chee and Kwai Mai Pink) cultivated in Sicily. Botryosphaeriaceae and Diaporthaceae were consistently isolated from symptomatic samples. Morphological characterization and multi-locus phylogenies using three genomic loci (a portion of translation elongation factor 1-α gene, a portion of the β-tubulin gene, and an internal transcribed spacer) identified these fungi as Neofusicoccum parvum, Lasiodiplodia theobromae, Botryosphaeria dothidea, Diaporthe foeniculina, and Diaporthe baccae on mango and Diaporthe foeniculina and Diaporthe rudis on litchi. Pathogenicity tests on healthy mango (cv. Kensington Pride) and litchi (cv. Way Chee) plants demonstrated the pathogenicity of the isolates used in the study, and Koch's postulates were fulfilled for all pathogens. To our knowledge, this is the first report of L. theobromae, B. dothidea, and Diaporthe species on mango in Italy and the first report worldwide of woody canker and shoot blight caused by D. foeniculina and D. rudis on litchi plants. [ABSTRACT FROM AUTHOR]

In the olive-growing areas of Apulia (southern Italy) where Xylella fastidiosa has caused enormous damage, there is a need to identify alternative crops. These could include pistachio ( Pistacia vera L.), but it is critical to define the impact of the bacterium on this crop and what are the main phytosanitary threats for this species in the areas where the bacterium is now endemic. Therefore, we started evaluating infections caused by X. fastidiosa , the fungus Neofusicoccum mediterraneum , and other pathogens on four pistachio cultivars ('Kerman', 'Aegina', 'Lost Hills', and 'Napoletana') grown in areas where X. fastidiosa has been present for a long time. X. fastidiosa was detected only in one orchard (incidence: 18% 'Napoletana' and 55% 'Kerman') out of six surveyed orchards, with low bacterium concentration (1.67 to 5.98 × 10 3 CFU ml -1 ) and no symptoms. N. mediterraneum was retrieved in three orchards just on the cultivar Kerman but with high incidence (up to 30%) and infection level quantified as molecular severity (6.82 to 7.43); no other pathogens were detected. The N. mediterraneum representative isolates characterized in this study showed similarity with Spanish and Portuguese isolates. A confocal microscope analysis for this host-pathogen association suggested no differences in plant response to fungal aggression between the cultivars Kerman and Aegina, but just lack of latent inoculum in 'Aegina' plants, pointing to a possible nursery origin of the infection. Waiting for additional targeted experiments to clearly define host response of pistachio cultivars to Xylella spp., this study also points at N. mediterraneum as a potential threat to this tree crop new for the area., Competing Interests: The author(s) declare no conflict of interest.

The Indian laurel-leaf fig (Ficus microcarpa) is an important ornamental tree widely distributed in the urban areas of Italy. Surveys conducted in 2019 and 2020 on several tree-lined streets, squares, and public parks in Catania and Siracusa provinces (Sicily, southern Italy) revealed the presence of a new disease on mature trees. About 9% of approximately 450 mature plants showed extensive branch cankers and dieback. Isolations from woody tissues obtained from ten symptomatic plants consistently yielded species belonging to the Botryosphaeriaceae family. The identification of the recovered fungal isolates was based on a multi-loci phylogenetic (maximum parsimony and maximum likelihood) approach of the ITS, tef1-α, and tub2 gene regions. The results of the analyses confirmed the presence of three species: Botryosphaeria dothidea, Neofusicoccum mediterraneum, and N. parvum. Pathogenicity tests were conducted on potted, healthy, 4-year-old trees using the mycelial plug technique. The inoculation experiments revealed that all the Botryosphaeriaceae species identified in this study were pathogenic to this host. Previous studies conducted in California showed similar disease caused by Botryosphaeriaceae spp., and the pathogenic role of these fungi was demonstrated. To our knowledge, this is the first report of Botryosphaeriaceae affecting Ficus microcarpa in Europe. [ABSTRACT FROM AUTHOR]

English walnut (Juglans regia) is an important nut crop worldwide and is currently considered emerging in Italy. Botryosphaeriaceae fungi cause symptoms including cankers, discoloration and dieback, and several species are reported across the world on walnut. In this study, symptomatic trees from an orchard in Southern Italy showing branch dieback, cankers, wood discoloration and gummosis were surveyed. Three different fungi from the Botryosphaeriaceae were consistently isolated from symptomatic tissues. Representative isolates were characterized using morphological and molecular approaches based on conidial morphology, optimum growth temperature and the comparison of DNA sequence data from the ITS, tef1‐α and tub2 loci. Three species were identified: Botryosphaeria dothidea, Neofusicoccum mediterraneum and Neofusicoccum parvum. Pathogenicity tests on detached fruits and potted plants showed that all three species were pathogenic. To our knowledge, this is the first report of these Botryosphaeriaceae species causing canker and dieback on English walnut in Italy. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs) are one of the most economically important diseases of grapevines, causing yield reductions and limiting vineyard lifespans. Fungal pathogens responsible for GTDs primarily infect grapevines through pruning wounds. The lack of systemic fungicides to stop the advance of fungi in vine vascular systems makes the use of pruning wound protection with either synthetic chemicals or biological control agents (BCAs) the main available GTD control strategy. Demands for sustainable grape production and increasing limitations on pesticide usage have raised interest in potential use of BCAs as pruning wound protectants against GTDs. The objectives of this study were to characterize 16 Trichoderma isolates from southern Italy using molecular methods, and to evaluate their potential activity as BCAs in vitro against the GTD canker-causing fungi Diplodia seriata, Eutypa lata and Neofusicoccum parvum. Molecular studies along with phylogenetic analyses identified eight species, including Trichoderma atroviride, T. guizhouense, T. harzianum, T. koningiopsis, T. longibrachiatum, T. paratroviride, T. paraviridescens, T. spirale, and one unidentified Trichoderma sp. All these species had optimum mycelium growth between 25 and 35°C. In vitro dual culture experiments assessed antagonistic capabilities of all the Trichoderma isolates against D. seriata, E. lata and N. parvum, and showed that the isolates inhibited mycelial growth of the pathogens by up to 70%. The most inhibitory isolates were tested in planta for capability to protect pruning wounds against D. seriata and N. parvum in a detached cane assay. All the selected Trichoderma isolates gave >80% control of D. seriata and 60% control of N. parvum, and protected pruning wounds for up to 21 d after treatment. [ABSTRACT FROM AUTHOR]

During June 2018, several symptomatic fig (Ficus carica) cuttings, showing twig blight, subcortical discolouration and apical dieback were collected from a nursery in Catania province, Sicily (Italy). Isolations from diseased tissue consistently showed the presence of the same fungal colony. Morphology of the fungal isolates together with sequence data of the nuclear rDNA internal transcriber spacer (ITS) region, translation elongation factor 1-alpha (tef1) gene and partial beta-tubulin (tub2) gene of representatives isolates revealed the presence of the fungus Neofusicoccum parvum. Pathogenicity tests were conducted by inoculating fig cuttings with mycelial plugs. After 10 days, the inoculated plants developed cankers similar to those observed in the greenhouse and after 26 days all inoculated plants were dead. To the best of our knowledge, this is the first report worldwide of N. parvum causing disease on this host. [ABSTRACT FROM AUTHOR]

Over the last 10 years, several fungi were isolated from grapevines with grapevine trunk disease (GTD) symptoms, in the Apulia and Molise regions of Italy. Morphological and molecular analyses allowed the identification of species belonging to Botryosphaeriaceae, Phaeoacremonium species, Phaeomoniella chlamydospora, Pleurostoma richardsiae and less-common fungi associated with grapevine trunk diseases, such as Cadophora, Colletotrichum, Seimatosporium and Truncatella. These last genera were isolated at significant frequencies, so they were investigated for possible involvement in GTDs. To screen the large numbers of isolates collected, microsatellite-PCR analysis was carried out with the M13 primer, and 29 strains were further studied by amplification of different genes, for multi-locus analyses. Phylogenies and morphological analyses allowed identification, for first time in Italy, of fungi associated with GTDs, including Cadophora luteo-olivacaea, Colletotrichum fioriniae, Seimatosporium vitis-vinifera and Truncatella angustata. Pathogenicity assays with these fungi and other fungi known to be pathogens for grapevines (Lasiodiplodia citricola, Phaeoacremonium italicum, Pleurostoma richardsiae) showed that they caused disease symptoms on two Italian grapevine cultivars ('Bombino bianco', 'Nero di Troia'), although with different degrees of severity. Among the fungi isolated for the first time in Italy, Sei. vitis-vinifera was the most aggressive, while C. fioriniae the least pathogenic. All of these fungi were re-isolated from grapevine, and thus fulfilled Koch's postulates, confirming their pathogenicity on grapevine. [ABSTRACT FROM AUTHOR]

In this study the production of secondary metabolites by a virulent strain of Sardiniella urbana, a recently described pathogen originally found on declining European hackberry trees in Italy, was investigated for the first time. Chemical analysis of the culture filtrate extracts led to the isolation of three well known compounds as R-(−)-mellein and (3R,4R)-and (3R,4S)-4-hydroxy melleins which were identified by spectroscopic methods (essentially NMR and ESIMS). The isolated compounds were tested for their phytotoxic, antifungal and zootoxic activities. Among them, only R-(−)-mellein was found to be active. [ABSTRACT FROM AUTHOR]

Severe dieback symptoms were recently observed on apple ( Malus × domestica ) trees in Northern Italy, representing a growing concern for producers. Surveys were conducted over a 3-year period (2019 to 2021), and five apple orchards, from 5 to 12 years old, were monitored. A total of 33 fungal isolates isolated from symptomatic plants was selected for characterization. The species identification was achieved through multilocus phylogenetic analyses performed on sequences of three genomic loci (ITS, tub2 , and tef1 ). Morphological features were assessed, and the average growth rate at different temperatures was determined. Seven species were identified in association with dieback of apple trees: Botryosphaeria dothidea , Cadophora luteo-olivacea , Diaporthe rudis , Diplodia seriata , Eutypa lata , Kalmusia longispora , and Paraconiothyrium brasiliense . All the species were pathogenic when inoculated on healthy apple plants. B. dothidea resulted in the most aggressive infections. This study provides an insight into the fungal species diversity associated with apple dieback and provides basis for further investigations to assess the phytosanitary status of plant materials to recommend and implement effective management strategies., Competing Interests: The author(s) declare no conflict of interest.

Isolates that resemble Dothiorella (Botryosphaeriaceae, Ascomycota) species were isolated from dead twigs, asymptomatic and necrotized bark of European hop hornbeam (Ostrya carpinifolia Scop.), Eurasian smoke tree (Cotinus coggygria Scop.) and common juniper (Juniperus communis L.) growing in western Slovenia and northern Italy. They were identified based on anamorph morphology and phylogenetic analyses of the ITS rDNA and EF-1α sequences, and previously designated as Dothiorella sp. A, B and C. This study has clarified the identity of these species by comparing them with other Dothiorella species known from culture based on gene sequence data, as well as morphological characters of the anamorphs. The phylogenetic results revealed three species, Dothiorella iberica, Dothiorella parva, and a Dothiorella sp. Isolates identified in the phylogenetic analyses as D. parva differed from the original description of this species and are thus described here based on the anamorph morphology. Isolates of D. parva were identified from O. carpinifolia in western Slovenia and northern Italy, and C. coggygria in western Slovenia, and coexist with Dothiorella sp. on O. carpinifolia in northern Italy. Dothiorella iberica was identified on J. communis in western Slovenia, thus expanding the geographic range of this species. This is the first record of D. parva from these hosts and countries. Our results indicate that these Dothiorella species occur widely across the Mediterranean region, and on a variety of hosts. [ABSTRACT FROM AUTHOR]

Species of Dothiorella are common plant pathogens or saprobes found mainly on a variety of woody hosts, with a cosmopolitan distribution. Strains of Dothiorella were isolated from the stems of Symphoricarpos sp. and Cornus sanguinea in Italy. Morphological characters, as well as phylogenetic analyses of the internal transcribed spacer region (ITS4, ITS5) and partial sequences of the translation elongation factor 1-α genes were used to characterize and distinguish the two isolates. One is conspecific to D. sarmentorum previously from Menispermum canadense collected in Sweden, and a description for this species is provided. The second species could not be assigned to any known species of Dothiorella. Dothiorella symphoricarposicola sp. nov. from Symphoricarpos is described and illustrated herein, and compared with similar Dothiorella taxa. [ABSTRACT FROM AUTHOR]

Twig cankers and diebacks were observed on cherry laurel ( Prunus laurocerasus L.) hedges located in a private garden of Perugia (Central Italy). Four fungal isolates, forming gray colonies and aerial mycelium, were obtained from cankers. For each isolate, Koch's postulates were fulfilled by inoculating cherry laurel plants. Based on cultural characteristics, rep-PCR and phylogenetic analyses on ITS and EF1- α nucleotides sequences, the isolates were identified as Diplodia seriata De Not. To the best of our knowledge, this is the first report of D. seriata as a new pathogen of P. laurocerasus. The severe symptoms and the wide distribution of the host plant make the pathogen potentially dangerous for this ornamental species. [ABSTRACT FROM AUTHOR]

In a recent survey of olive groves in the Canosa di Puglia, Cerignola and Foggia areas of southern Italy a serious decline of olive trees was seen. The symptoms comprised a general decline of the trees beginning with foliar browning and leaf drop, wilting of apical shoots, die-back of twigs and branches, and brown streaking under the bark of the trunk, branches and twigs. In more advanced stages of the disease necroses and cankers were observed on the bark. The symptoms were similar to those caused by Verticillium wilt, but morphological and molecular analyses revealed the presence of Pleurostomophora richardsiae, Phaeoacremonium aleophilum and various genera and species in the Botryosphaeriaceae. Pathogenicity tests carried out on young shoots showed that Pl. richardsiae, Pm. aleophilum and Neofusicoccum parvum were pathogenic and capable of causing brown wood streaking. Since Pl. richardsiae was the most aggressive of these three fungi and frequently it was the only one isolated from diseased trees it was considered to be a primary cause of the decline. To our knowledge, this is the first report of Pl. richardsiae as a pathogen of olive trees. [ABSTRACT FROM AUTHOR]

Branch dieback was observed on Phoenicean juniper trees, in a natural growing area on Caprera Island (Italy), during 2009 and 2010. Fungal isolates obtained from symptomatic twigs and branches showing dieback and bark necrosis were identified as Diplodia africana by analysis of morphological features and genomic DNA sequences of the ITS region and translation elongation factor 1-α gene. Pathogenicity was verified by stem inoculation of 3-year-old saplings of Phoenicean juniper. This is the first report of D. africana in the northern hemisphere, and of this fungus as a pathogen of Phoenicean juniper. [ABSTRACT FROM AUTHOR]

This is the first report of Neofusicoccum australe associated with grapevine dieback in Italy. Fungal isolates obtained from symptomatic tissues were identified on the basis of morphological and cultural characteristics as well as ITS sequence data. Pathogenicity was verified by inoculation of excised green grapevine shoots from cv. Cannonau under controlled laboratory conditions. [ABSTRACT FROM AUTHOR]

The first report of a dieback of grapevine caused by Lasiodiplodia theobromae in Sicily (Italy) is given. About twelve per cent of the vines in the cv. Insolia vineyard surveyed, showed spur dieback, retarded growth and wood necrosis. Isolation trials and pathogenicity tests are briefly reported, together with morphological, cultural and molecular characters on which identification was based. [ABSTRACT FROM AUTHOR]

In Italy, after the first report in Friuli-Venezia Giulia along the border with Slovenia in 2009, ash dieback has successively been reported in Veneto, Tuscany and Trentino-Alto Adige. Given its alarming expansion in European ash formations along the sub-montane belt of north-eastern Italy and the limited information about the associated fungal microorganisms; since 2017, a study has been conducted in order to isolate and characterize the fungal species involved in the aetiology of the disease. The surveys were conducted in six ash–maple forests distributed along the Veneto and Friuli-Venezia Giulia pre-Alpine regions (Italy). In each site, the health status of ash trees was assessed and a sample (shoot or branch) with the typical symptoms of the disease was taken from ten trees to isolate the associated pathogens. The fungal colonies developed were identified using morphological features and DNA sequences. The 60 samples processed yielded a total of 109 fungal isolates belonging to 9 families including: Botryosphaeriaceae (62 isolates), Diaporthaceae (18), Nectriaceae (10), Didymellaceae (9), Helotiaceae (5), Diatrypaceae (2), Didymosphaeriaceae (1), Phaeosphaeriaceae (1) and Valsaceae (1). In particular, three species—Diplodia subglobosa, Diplodia fraxini and Diaporthe eres—were isolated with high frequency, while Hymenoscyphus fraxineus was isolated from only five plants distributed in four sites. The pathogenicity tests, conducted on 3-year-old seedlings, detached branches (3–4 cm diameter), and leaves of Fraxinus excelsior, showed that Diplodia fraxini is the most virulent species and the only one able to reproduce the symptoms observed in nature. Overall, the results obtained emphasize that several fungal pathogens are involved in the aetiology of the disease, many of which belong to the Botryosphaeriaceae family. [ABSTRACT FROM AUTHOR]

During the winter of 2018 symptoms of leaf and twig blight were observed on about 15% of 7500 4-year-old potted plants of Indian hawthorn [ I Rhaphiolepis indica i (L.) Lindl.] This fungus is spreading in Sicily on different important crops (Guarnaccia et al. [1]; Ismail et al. [2]) but for our knowledge, this is the first report of leaf and twig blight caused by I N. parvum i on Indian hawthorn. [Extracted from the article]