Both biotic and abiotic factors are raising concerns about Mediterranean oak forests resilience to climate change, particularly Holm oak (Quercus ilex L.) forests. In the last decade, many drought events impacted this species in several Mediterranean countries, and a widespread decline of holm oak forests has been observed due to a combination of drought and the soil pathogen Phytophthora cinnamoni. In addition, climate change has induced a rise in mean winter temperatures, a seasonal shift of precipitation from summer to wintertime, and a tendency towards heavy rain and prolonged droughts, which are triggering factors for the current decline of holm oak in Mediterranean regions. The resulting reduction in holm oak forest vitality and productivity can ultimately lead to profound changes in ecosystem processes and functions. Previous studies based on tree-ring δ13C and SSR genotyping showed that different holm oak populations can differ in their water use efficiency, resulting in different drought tolerance. This study highlighted the potential of this analysis for the selection of seed-bearing genotypes aimed to preserve Mediterranean holm oak ecosystem and improving its forest management. In this context, LIFE RECLOAK project aims to restore and improve the conservation status of threatened forests by holm oak dieback using genotypes characterized by high level of drought tolerance and pathogen resistance. A step-by-step approach will allow the achievement of this ambitious goal over the five years of the project. In the first instance, drought-tolerant and pathogen-resistant genotypes will be selected through a genetic screening based on SSR genotyping and the identification of genetic markers associated with stress tolerance. A mesocosm trial will be carried out to confirm the drought tolerance and the pathogen resistance of the holm oak genotypes. Then, the selected seedlings will be planted in four pilot sites areas located in Mediterranean holm oak forests included in Natura 2000 network and affected by widespread dieback: Monti dell’Uccellina in Parco della Maremma (Tuscany, Italy); Parco della Maddalena (Sardinia, Italy); Muela de Cortes y el Caroche (Valencia province, Spain), Raso del Conejo Forest (Sierra Morena, Andalucia, Spain) and Wied il-Mielaħ u l-Inħawi tal-Madwar (Malta). After that, seasonal and multi-year monitoring for three years after the plantation will begin at each pilot site. The monitoring of pilot sites will be done by visual assessment and through the measurement of plant physiological performances by integrating gas exchange measurements with proximal sensing measures. The effects of reforestation on ecosystem functioning and climate mitigation will be investigated by measuring soil moisture, respiration, and microbial communities’ composition, as well as monitoring understory and overstory vegetation cover and biomass accumulation. Overall, this project will provide a reliable demonstration of restoring forest structure, thereby promoting forestry with conservation objectives and opening the possibility of restoring other Mediterranean areas affected by holm oak dieback.

Phytophthora is a long-established, well-known, and globally important genus of plant pathogens. Phylogenetic evidence has shown that the biologically distinct, obligate biotrophic downy mildews evolved from Phytophthora at least twice. Because, cladistically, this renders Phytophthora "paraphyletic," it has been proposed that Phytophthora evolutionary clades be split into multiple genera (Crous et al. 2021; Runge et al. 2011; Thines 2023, 2024). In this letter, we review arguments for the retention of the generic name Phytophthora with a broad circumscription made by Brasier et al. (2022) and by many delegates at an open workshop organized by The American Phytopathological Society. We present our well-considered responses to the genus splitting proposals, both in general terms and in terms of the specific proposals for new genera, alongside new information regarding the biological properties and mode of origin of the Phytophthora clades. We consider that the proposals are mostly non-rigorous and not supported by the scientific evidence. Further, given (i) the apparent lack of any distinguishing biological characteristics (synapomorphies) between the Phytophthora clades; (ii) the fundamental monophyly of Phytophthora in the original Haeckelian sense (Haeckel 1877); (iii) the fact that paraphyly is not a justification for taxonomic splitting; and (iv) the considerable likely damage to effective scientific communication and disease management from an unnecessary breakup of the genus, we report that workshop delegates voted unanimously in favor of preserving the current generic concept and for seeking endorsement of this view by a working group of the International Commission on the Taxonomy of Fungi. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

This work focuses on developing an automated system for detecting downy mildew and powdery mildew symptoms in grapevines, with particular attention to the role of data partitioning and dataset diversity in ensuring reliable model performance. Leveraging deep learning techniques, specifically the YOLO (You Only Look Once) object detection model, we aimed to provide a robust tool for disease detection, which is crucial for optimizing vineyard management, increasing crop yield, and promoting sustainable agricultural practices. Over two years, we collected and expertly annotated a large dataset of images depicting downy and powdery mildew symptoms in field conditions. The YOLO model was trained and validated on this dataset, achieving a mean Average Precision (mAP) of 0.730, demonstrating good detection accuracy. A key contribution of this study is the emphasis on the importance of proper data partitioning strategies, showing that random image partitioning can lead to an overestimation of model performance. Our findings underscore that true improvements in detection accuracy are driven not merely by increasing the number of images but by enhancing the diversity of the dataset, particularly for the areas, seasons, growth stages, and conditions in which the images are captured. This approach ensures a more realistic assessment of the system's performance, critical for deploying such systems in practical, real-world agricultural scenarios. The results highlight the potential of deep learning models to enhance vineyard management through a reliable and efficient detection of diseases in real-world conditions.

This review aims to address the specific challenges of forest decline in Mediterranean Fagaceae ecosystems driven by the alien invasive Phytophthora cinnamomi and global changes. In a scenario of climate change and anthropic pressure, this review seeks to offer a comprehensive overview of the current state of P.cinnamomi invasion, focusing on its biology, ecology and epidemiology in different Mediterranean forest ecosystems, and providing an update on diagnosis, impact and current management measures. Recent studies have significantly advanced our understanding of the decline of Mediterranean Fagaceae forests driven by Phytophthora spp. The introduction of the plant holobiont concept and microbial invasion biology and ecology has reshaped the study of plant–microbe interactions. This perspective, which considers the tree as an ecosystem composed of the tree itself together with its associated microbiome has been pivotal in developing holistic management strategies to mitigate pathogen impacts. The network of interactions between components of the microbial community of healthy and diseased trees, has been the object of several recent studies that highlighted the complex dynamics of host–pathogen interaction and offered the option for biotechnological applications including the use of helper microorganisms and antagonists. The collaboration among research institutions from Italy, Spain and Portugal has resulted in a detailed review that emphasizes the importance of tailored management protocols for different ecosystems. Engaging stakeholders and citizens in integrated pest management (IPM) strategies has proven crucial for effective forest management. The findings underscore the need for continuous monitoring, innovative treatment methods, and public awareness to mitigate the impacts of Alien Invasive Forest Phytophthoras (AIFPs) and ensure the sustainability of Mediterranean Fagaceae forests.

Purpose Site-specific field management operations represent one of the fundamental principles of precision viticulture. The purpose of the research is to observe and analyse the evolution of a vineyard over three consecutive years to understand which factors most significantly influence the quality of the vineyard's production. Methods The research involved technologically advanced tools for crop monitoring, such as remote and proximal sensors for vegetation surveys. In association, grape quality analyses were performed through laboratory analysis, constructing geostatistical interpolation maps and matrix correlation tables. Results Both remote and proximal sensing instruments demonstrated their ability to effectively estimate the spatial distribution of vegetative and quality characteristics within the vineyard. Information obtained from GNDVI and CHM proved to be valuable and high-performance tools for assessing field variability. The differentiated plant management resulted in uniform production quality characteristics, a change evident through the monitoring techniques. Conclusion The research highlights the effectiveness of using advanced technological instruments for crop monitoring and their importance in achieving uniformity in production quality characteristics through differentiated plant management. From the results obtained, it was possible to observe how differentiated plant management led to a uniformity of production quality characteristics and how the monitoring techniques can observe their evolution. This result represents a positive accomplishment in field management during the three monitoring years, responding to the principles and objectives of precision agriculture.

Wild olive represents one of the most iconic woody plants in the Mediterranean Basin. This slow-growing evergreen tree is characteristic of sclerophyll vegetation, extremely tolerant to drought, salinity and diseases, thus is commonly used as rootstock for grafting cultivated olive varieties. Since 2022, extensive dieback and mortality of wild olive trees have been observed in Sardinia, Italy. Affected plants showed leaf chlorosis, wilting, defoliation, shoot blight and epicormic shoots, often associated with root rot and necroses on the feeder roots, initially associated with Phytophthora bilorbang and P. pseudocryptogea. A 2-year study was thereafter conducted to clarify the aetiology of this unusual disease. Using a baiting technique, 10 Phytophthora taxa from three phylogenetic clades (2, 6, 8) were isolated from 53 of 87 rhizosphere soil samples collected, including P. asparagi, P. bilorbang, P. crassamura, P. inundata, P. kelmanii, P. oleae, P. pseudocryptogea, P. sansomeana and P. syringae. Additionally, some isolates that showed several polymorphisms in rDNA internal transcribed spacer (ITS) sequences compared with closely related known species are reported here as P. taxon paulensis. Pathogenicity tests on 1-year-old wild olive seedlings showed that nine out of 10 Phytophthora taxa significantly reduced root length of inoculated seedlings compared to controls. P. inundata and P. oleae caused the greatest reduction, while root length of seedlings inoculated with P. kelmanii did not differ from the controls. This study provides insights into the role of Phytophthora taxa in the wild olive decline in Sardinia, indicating the urgent need to expand monitoring and implement effective management strategies to mitigate the disease.

In viticulture, the site-specific management of the crop in its environmental and vegetative-productive variables has played a fundamental role in the differentiation of production strategies. This study aimed to observe how the multi-temporal terrestrial and aerial survey identified homogeneous areas in a vineyard located in Usini (Italy), considering decision support maps obtained through geostatistical analysis of the data and defining the most appropriate period for the recognition of differentiated management zones. The obtained maps helped identifying homogeneous zones for differentiated management, highlighting variables convergence only on the last monitoring date. The maps obtained during the phenological phases before harvesting was the most appropriate for the evaluation of site-specific variability in vineyards in the Mediterranean environment, contributing to the improvement of the management of agronomic practices by the decision support system provided by Precision Agriculture technologies.

Wild olive (Olea europaea var. sylvestris) is a sclerophyllous drought-tolerant tree native to the Mediterranean basin, which is used as a hardy and disease-resistant rootstock on which scions of cultivated olive varieties are grafted (Breton et al., 2006). In Sardinia, Italy, wild olive is a significant component of the agroforestry landscape, and its ancient origin is proven by the presence of several millennial trees. In March 2022, extensive dieback and mortality of wild olive trees were observed in an area of c. 200 ha, located 5 km south from Paulilatino in central Sardinia (Fig. 1). Three separate plots were examined and in each the trees showed severe leaf chlorosis, wilting or defoliation of the whole crown (Fig. 2). Often these symptoms were associated with root rot and necrotic lesions on the feeder roots (Fig. 3). In the investigated sites, estimated tree mortality and disease incidence were 60 and 80%, respectively. Rhizosphere soil was sampled from a total of 16 unhealthy trees and subjected to a baiting technique, using fresh Ceratonia siliqua leaves as baits (Perez-Sierra et al., 2022). Isolations were also made by plating small fragments of root phloem tissue from lesion margins onto Phytophthora selective medium (SMA) (Brasier et al., 2005). A homothallic Phytophthora species was consistently isolated from 14 of the sampled trees. An additional Phytophthora species was detected from the rhizosphere of four diseased trees. Developing colonies were transferred onto carrot agar, and DNA extracted for amplification and sequencing of ITS and cox1 genes. A BLAST search in GenBank showed 99–100% identity with sequences of the ex-type cultures of P. bilorbang (CBS131653) and P. pseudocryptogea (CBS139749). Sequences of a representative isolate for each species were submitted to GenBank (Accession Nos. OP801844, OP801845, OP856579 and OP856580). The pathogenicity of both Phytophthora species was verified using six-month-old wild olive seedlings and the soil infestation method (Perez-Sierra et al., 2022). Three weeks after inoculation with P. bilorbang and P. pseudocryptogea, all seedlings showed wilting and dieback, and the fine root weight of inoculated plants was reduced by 68 and 42%, respectively, in relation to non-inoculated controls (Fig. 4). Both species were re-isolated from necrotic roots, thus fulfilling Koch's postulates. This is the first report of P. bilorbang on wild olive worldwide. However, this species was recently detected in Calabria, Italy, causing root rot on 15-year-old cultivated olive trees originating from Sardinia (Santilli et al., 2020). In contrast, P. pseudocryptogea was previously reported on wild olive in Spain together with other Phytophthora species (González et al., 2019). Further investigations are required to better understand the epidemiology of the disease and other possible factors involved in the decline. A consequence of this damaging new disease is that further use of wild olive as a source of rootstock for grafting olive varieties could be limited. We thank the local municipality of Paulilatino for their logistic support in the field surveys.

Esca proper and Botryosphaeria dieback are among the most widespread Grapevine trunk diseases (GTDs), characterized by similar decline symptoms. In the present work, chronic, apoplexy and death symptoms were analysed separately in four vineyards and four different cultivars, on more than 1,000 vines per cultivar, taking into account ten-year annual surveys. The cumulative incidence of plants with chronic symptoms (CHR) reached high values on 'Sauvignon Blanc' (81.9 %), 'Cabernet Sauvignon' (79.4 %) and 'Cannonau' (66.5 %), but it was low on 'Merlot' (25.1 %). 'Sauvignon Blanc' showed the highest cumulative incidence of apoplectic events (23.1 %) and dead cordons (49.2 %), while 'Cannonau' had the greatest number of dead plants (28.8 %). In each symptom category, incidence among cultivars differed significantly according to chi(2) test at P <= 0.05. Annual incidence of foliar symptoms fluctuated over ten years (ranging from 0.9-9.5 % in 'Merlot' to 6.3-59.1 % in 'Cabernet Sauvignon'), mostly with regard to CHR. On average, every year only 33.9 % of plants showing CHR had expressed symptoms in the previous year, while 48.6 % did not show symptoms the following year. Conversely, most of the plants exhibiting apoplexy or death were symptomatic the previous year. According to Tuckey HSD test (P <= 0.05) 'Merlot' had the highest incidence of plants showing CHR symptoms for the first time (72.1 %) and of apparently recovered plants (76.3 %), while 'Cabernet Sauvignon' exhibited the highest incidence of plants showing CHR symptoms also the previous year (50.0 %). The 'Cabernet Sauvignon' attitude to show chronic symptoms with a certain continuity was also confirmed by the low incidence of plants with hidden symptoms (lack of symptoms in previously symptomatic vines). On the contrary, the incidence of acute symptoms (apoplectic events and dead plants) was quite low on 'Cabernet Sauvignon'. The present study confirms that GTD incidence is influenced by cultivar. All the cultivars assessed were susceptible, but with differences in intensity, type (chronic or acute) and fluctuation of symptoms. It cannot be excluded, however, that besides the genotype also external factors, as the vigour conferred by the type of soil or the combination with the rootstock, may have influenced the results.

Monitoring surveys of Phytophthora related diseases in four forest nurseries in Italy revealed the occurrence of fourteen Phytophthora species to be associated with collar and root rot on fourteen plants typical of Mediterranean and alpine regions. In addition, a multilocus phylogeny analysis based on nuclear ITS and ß-tubulin and mitochondrial cox1 sequences, as well as micromorphological features, supported the description of a new species belonging to the phylogenetic clade 7c, Phytophthora mediterranea sp. nov. Phytophthora mediterranea was shown to be associated with collar and root rot symptoms on myrtle seedlings. Phylogenetically, P. mediterranea is closely related to P. cinnamomi but the two species differ in 87 nucleotides in the three studied DNA regions. Morphologically P. mediterranea can be easily distinguished from P. cinnamomi on the basis of its smaller sporangia, colony growth pattern and higher optimum and maximum temperature values. Data from the pathogenicity test showed that P. mediterranea has the potential to threaten the native Mediterranean maquis vegetation. Finally, the discovery of P. cinnamomi in alpine nurseries, confirms the progressive expansion of this species towards cold environments, probably driven by climate change.

Field surveys conducted on nine farms over a 2-year period showed the widespread presence of Phytophthora-related diseases on globe artichoke plants in the main growing area in Sardinia (Italy). Characteristic symptoms included wilting and necrosis of the outermost leaves and dark brown discoloration of stem tissues, as well as root rot. A total of 18 Phytophthora colonies belonging to three species were isolated and characterized. Based on morphological features and ITS sequence data, Phytophthora isolates were identified as P. crassamura (eight isolates) and P. cactorum (four isolates). Six isolates could not be assigned to any formally described species of Phytophthora and are therefore described here as Phytophthora marrasii sp. nov. The ITS phylogeny places P. marrasii in a terminal clade basal to the sister taxa (P. foliorum, P. hibernalis, P. lateralis, and P. ramorum) of the clade 8c. In particular, P. marrasii is phylogenetically related to P. foliorum, a species from which it differs in 62 nucleotides in the ITS region. At the same time, it can easily be distinguished morphologically from P. foliorum mainly because of the low minimum temperature for growth, the bigger and persistent non-papillate sporangia, and smaller oogonia. Pathogenicity tests confirmed that all three Phytophthora species are pathogenic on globe artichokes, which represent a new host for these pathogens.

Severe trunk and branch diseases of hazelnut trees have recently been observed in several groves in Sardinia (Italy). Since there is little information about the aetiology of these diseases and given the high ecological and economic importance of these agro-systems, an in-depth study was carried out. From autumn 2012 to spring 2014, sixty samples of twigs and branches of hazelnut trees showing exudates and different types of canker (sunken with wedge-shaped necrotic sector, open canker and Cytospora canker) were collected in the main hazelnut growing area in the centre of the island. Based on morphology, colony appearance and DNA sequence data, seven species belonging to four genera and three families were isolated and identified. These included Diplodia sapinea, D. seriata, Dothiorella iberica, Do. parva and Do. symphoricarposicola (Botryosphaeriaceae), Gnomoniopsis smithogilvyi (Gnomoniaceae) and Anthostoma decipiens (Diatrypaceae). In addition, two new species namely Diaporthella cryptica sp. nov. and Dothiorella omnivora sp. nov. are described. Pathogenicity trials carried out on wounded hazelnut branches showed that three species, Anthostoma decipiens, Diaporthella cryptica and Diplodia seriata are aggressive pathogens on hazelnut. Results obtained have allowed us to clarify, almost a century after its first description, the aetiology of the disease known as Cytospora canker of hazelnut and to reveal the existence of three evolutionarily distinct lineages for its causal agent A. decipiens. The diversity of fungal pathogens associated with twig and branch cankers of hazelnut is greater than previously recognised and further studies are necessary to determine the exact role played by each species and their possible synergistic interaction.

The rapid growth and environmental adaptability of Eucalyptus species has favored their global cultivation for pulpwood production. On the island of Sardinia, Italy, eucalypt plantations were established in the 20th century primarily in areas reclaimed from marshland, but the trees are now grown all over the island as ornamentals or windbreaks, and for timber, pulp and honey production. In recent years, an unusual decline and mortality of unknown etiology has been observed in Eucalyptus camaldulensis (river red gum) plantations throughout the island. Given the ecological and economic importance of eucalypt ecosystems in Sardinia, a survey was carried out in 2013 to determine which insect pests and fungal pathogens are directly involved in these phenomena. Field surveys throughout the island revealed severe infestations with the red gum lerp psyllid (Glycaspis brimblecombei) at all 12 surveyed sites, with the greatest numbers of pre-imaginal stages and adults occurring between May and July. The adult population reached its peak in July, followed 2 months later by the peak population of its specific parasitoid, Psyllaephagus bliteus. Symptoms of leaf chlorosis, crown thinning, shoot and branch dieback, sunken cankers, epicormic shoots and exudations of kino gum were also observed at the 12 field sites. Symptomatic woody samples yielded fungal isolates representing three distinct families: Botryosphaeriaceae, Diaporthaceae and Valsaceae. Morphological and DNA sequence data revealed seven distinct fungal species, namely Diaporthe foeniculina, Neofusicoccum australe, N. luteum, N. mediterraneum, N. parvum, N. vitifusiforme and Valsa fabianae. Two putative new species of Cytospora were also identified. Neofusicoccum australe was the only species recovered from all 12 sites, with isolation frequencies of 51-95%. Pathogenicity trials revealed that all Neofusicoccum species except N. vitifusiforme are directly involved in the etiology of the observed decline in the E. camaldulensis population on Sardinia.

The diversity of Botryosphaeriaceae species associated with “Botryosphaeria dieback” of grapevine was investigated in 18 vineyards in Sardinia, Italy. Lasiodiplodia isolates obtained from different woody hosts including holm oak, sweet orange and broom bush in Italy, Algeria and Tunisia were also characterized. Morphological and cultural characteristics as well as ITS and EF1-α sequence data were used to identify the fungal isolates. Forty-eight botryosphaeriaceous isolates were obtained from 113 symptomatic grapevine samples, from which ten species were identified. Diplodia seriata was the dominant species (25 % of isolates), followed by Neofusicoccum parvum (21.7 %). Two species, Diplodia olivarum and D. africana are reported for the first time on grapevine. In addition, two new species namely Lasiodiplodia mediterranea sp. nov. from grapevine, holm oak and sweet orange and Lasiodiplodia exigua sp. nov. from broom bush are described. In artificial inoculation experiments conducted on excised green grapevine shoots and lignified canes as well as holm oak seedlings, L. mediterranea was shown to be an aggressive pathogen.

Shoot blight was observed on Erica arborea L., in a natural growing area on Caprera Island (Italy), during 2011 and 2012. Fungal isolates obtained from 324 symptomatic shoots were identified as Neofusicoccum luteum by analysis of morphological and cultural characteristics, as well as DNA sequence data of the Internal Transcribed Spacer (ITS) of the ribosomal DNA and part of the translation Elongation Factor 1-alpha (EF-1α) gene. Pathogenicity of the fungus was verified by stem inoculation of 3-year-old seedlings of E. arborea. This is the first report of N. luteum as a pathogen of E. arborea.

The Mediterranean basin is recognized as a global biodiversity hotspot accounting for more than 25,000 plant species that represent almost 10% of the world’s vascular flora. In particular, the maquis vegetation on Mediterranean islands and archipelagos constitutes an important resource of the Mediterranean plant diversity due to its high rate of endemism. Since 2009, a severe and widespread dieback and mortality of Quercus ilex trees and several other plant species of the Mediterranean maquis has been observed in the National Park of La Maddalena archipelago (northeast Sardinia, Italy). Infected plants showed severe decline symptoms and a significant reduction of natural regeneration. First studies revealed the involvement of the highly invasive wide-host range pathogen Phytophthora cinnamomi and several fungal pathogens. Subsequent detailed research led to a better understanding of these epidemics showing that multiple Phytophthora spp. were involved, some of them unknown to science. In total, nine Phytophthora species were isolated from rhizosphere soil samples collected from around symptomatic trees and shrubs including Asparagus albus, Cistus sp., Juniperus phoenicea, J. oxycedrus, Pistacia lentiscus and Rhamnus alaternus. Based on morphological characters, growth-temperature relations and sequence analysis of the ITS and cox1 gene regions, the isolates were identified as Phytophthora asparagi, P. bilorbang, P. cinnamomi, P. cryptogea, P. gonapodyides, P. melonis, P. syringae and two new Clade 6 taxa which are here described as P. crassamura sp. nov. and P. ornamentata sp. nov. Pathogenicity tests supported their possible involvement in the severe decline that is currently threatening the Mediterranean maquis vegetation in the La Maddalena archipelago.

In this study, a strain (BL 101) of a species of Lasiodiplodia, not yet formally described, which was isolated from declining grapevine plants showing wedge-shaped cankers, was investigated for its ability to produce in vitro bioactive secondary metabolites. From culture filtrates of this strain three jasmonic acid esters, named lasiojasmonates A-C and 16-O-acetylbotryosphaerilactones A and C were isolated together with (1R,2R)-jasmonic acid, its methyl ester, botryosphaerilactone A, (3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone and (3R,4S)-botryodiplodin. The structures of lasiojasmonates A-C were established by spectroscopic methods as (1R*,2R*,3'S*,4'R*,5'R*)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone, (1R*,2R*,3'S*,4'R*,5'R*,10'R*,12'R*,13'R*,14'S*) and (1R*,2R*,3'S*,4'R*,5'R*,10'S*,12'R*,13'R*,14'S*)-4-(4-hydroxymethyl-3,5-dimethyltetrahydro-furan-2-yloxymethyl)-3,5-dimethyldihydro-2-furanones jasmonates (1, 4 and 5). The structures of 16-O-acetylbotryosphaerilactones A and C were determined by comparison of their spectral data with those of the corresponding acetyl derivatives obtained by acetylation of botryosphaerilactone A. The metabolites isolated, except 4 and 5, were tested at 1mg/mL on leaves of grapevine cv. Cannonau and cork oak using the leaf puncture assay. They were also tested on detached grapevine leaves at 0.5mg/mL and tomato cuttings at 0.1mg/mL. In all phytotoxic assays only jasmonic acid was found to be active. All metabolites were inactive in the zootoxic assay at 50 μg/mL.

In this study a new 20-nor-ent-pimarane, named diplopimarane, was isolated together with sphaeropsidins A (9) and C (10), and (+)-epiepoformin (11) from organic crude extracts of Diplodia quercivora, a recently described oak pathogen originally found on declining Quercus canariensis trees in Tunisia. Diplopimarane was characterized as (1S,2R)-2,8,8-trimethyl-2-vinyl-1,2,3,4,5,6,7,8-octahydrophenanthrene-1,9,10-triol by spectroscopic, X-ray, optical, and chemical methods. It exhibited a wide range of activities including remarkable phytotoxicity on nonhost plants such as tomato cuttings, moderate antifungal activity against important plant pathogens, and moderate zootoxicity against Artemia salina. Its derivatives (2-4 and 6) were also tested for their phytotoxic and zootoxic activities. All these derivatives proved to be active against A. salina at 200 μg/mL, while 2 and 6 were also active on tomato cuttings. The other secondary metabolites (9, 10, and 11) herein reported for D. quercivora exhibited phytotoxic, antifungal, and zootoxic activity. This is the first report on the secondary metabolites secreted in vitro by this oak pathogen that could be key components of its adaptative strategies.