First report of Neofusicoccum parvum and Phytophthora palmivora causing fruit rot of pomegranate in Italy

Severe pomegranate yield losses due to fruit diseases have recently been observed in several orchards in Veneto (north-eastern Italy). Given the economic relevance of these emerging diseases, an in-depth study was conducted in ten orchards distributed in the main producing areas in order to investigate the aetiology. From autumn 2020 to autumn 2023, eighty-two symptomatic fruits were sampled to isolate the causal agents. Based on morphology, colony appearance and DNA sequence data, seventy-seven isolates were obtained and identified. These included Coniella granati (Fam. Schizoparmaceae, 39 isolates), Neofusicoccum parvum (Fam. Botryosphaeriaceae, 29) and Phytophthora palmivora (Fam. Peronosporaceae, 9). Pathogenicity trials conducted on ripe pomegranate fruits confirmed the aggressiveness of the three species. Results obtained have allowed us to expand knowledge on emerging pomegranate pathogens. Neofusicoccum parvum and P. palmivora are reported here for the first time as fruit rot agents on pomegranate in Italy

Performance of the ALICE experiment at the CERN LHC

ALICE is the heavy-ion experiment at the CERN Large Hadron Collider. The experiment continuously took data during the first physics campaign of the machine from fall 2009 until early 2013, using proton and lead-ion beams. In this paper we describe the running environment and the data handling procedures, and discuss the performance of the ALICE detectors and analysis methods for various physics observables

Multiplicity dependence of jet-like two-particle correlation structures in p-Pb collisions at 1asNN=5.02 TeV

Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p\u2013Pb collisions at a nucleon\u2013nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 < pT,assoc < pT,trig < 5.0 GeV/c is examined, to include correlations induced by jets originating from low momentum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range |\u3b7| < 0.9. The near-side long-range pseudorapidity correlations observed in high-multiplicity p\u2013Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton\u2013parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p\u2013Pb collisions. Further, the number scales only in the intermediate multiplicity region with the number of binary nucleon\u2013nucleon collisions estimated with a Glauber Monte-Carlo simulation

First report of Diplodia fraxini and Diplodia subglobosa causing canker and dieback of Fraxinus excelsior in Slovenia

Over the last decades the vitality and productivity of European ash trees in Slovenia has been seriously impacted by the onset of canker and dieback disease symptoms on young and old trees, primarily identified as ash dieback caused by Hymenoscyphus fraxineus. Given the limited information available about the aetiology of this emerging disease, a study was carried out to isolate, identify and characterize the fungal species involved in the observed ash symptoms. Field surveys were conducted in five forest sites where 50 symptomatic branch samples were collected. All samples were inspected and used for fungal isolation. Based on morphology, colony appearance and DNA sequence data of the internal transcribed spacer region (ITS), 125 fungal colonies belonging to five species were isolated and identified. Only a few symptomatic ash samples yielded colonies of H. fraxineus, whereas Botryosphaeriaceae species were isolated with a high frequency, with Diplodia fraxini as the dominant species. A pathogenicity test proved that all isolated species were pathogenic on European ash, causing bark lesions and wood discoloration. All Botryosphaeriaceae species isolated in this study are reported for the first time on European ash in Slovenia

Pathogenic fungi and oomycetes causing dieback on Fraxinus species in the Mediterranean climate change hotspot region

Environmental changes are occurring on a global scale, but their effects are most pronounced in climate change hotspot zones, such as the Mediterranean basin. Within this area Italy, extending from its southern coasts in the core of the Mediterranean Sea to its northernmost pre-Alpine and Alpine regions, is characterized by a variety of climatic conditions and vegetation types. Surveys conducted in 2018–2022 in forest formations of Central-Northern Italy revealed that the enhanced warming trend and irregular distribution of precipitations are strongly impacting the health of Fraxinus species, with some pathogenic fungi and oomycetes being important contributing factors to the decline of the three main ash species growing there: common ash (Fraxinus excelsior), flowering ash (Fraxinus ornus), and narrow-leaved ash (Fraxinus angustifolia). Isolation from symptomatic plant material collected countrywide under different site conditions and pathogenicity tests revealed a complex phytopathological framework, with several pathogenic species in addition to Hymenoscyphus fraxineus involved with a prominent role in the ash dieback etiology. Key microbial taxa included the fungal and oomycete pathogens Botryosphaeria dothidea, Diplodia fraxini, Diplodia subglobosa, Phytophthora acerina, and Phytophthora plurivora. The disease impact was higher on sites where ash trees grew under environmental stress (i.e., areas characterized by mild dry winters, hot summers with intense and prolonged drought) and exhibited reduced vigor, also as a consequence of anthropogenic interference (i.e., silvicultural management and fires). The identified causative agents are emerging pathogens that thrive under warmer conditions, their impact in the investigated areas being prevalent compared to H. fraxineus, which appears to be restricted on the Italian peninsula to the cooler and wetter valleys of the Alps and Central-Northern Apennines

Coniella granati and Phytophthora palmivora the main pathogens involved in pomegranate dieback and mortality in north-eastern Italy

Severe branch dieback, root rot and sudden death symptoms have recently been observed on pomegranate in several orchards in Veneto (north-eastern Italy). Since there is little information about the aetiology of these diseases and given the growing economic interest in this crop, an in-depth study was conducted. From winter 2017 to autumn 2018, forty-five symptomatic plants in two orchards were monitored and sampled to isolate the associated pathogens. Based on morphology, colony appearance and DNA sequence data, eight species belonging to seven genera and five families were isolated and identified. These included Botryosphaeria dothidea and Neofusicoccum parvum (Botryosphaeriaceae), Diaporthe eres (Diaporthaceae), Coniella granati (Schizoparmaceae), Cytospora punicae (Valsaceae), Phytophthrora palmivora, P. pseudocryptogea and Phytopythium vexans (Peronosporaceae). Pathogenicity trials conducted on 3-year-old pomegranate seedlings showed that three species, C. granati, N. parvum and P. palmivora are aggressive pathogens on pomegranate. Results obtained have allowed us to establish that the number of pathogens associated with emerging diseases of pomegranate is greater than previously recognised. Further studies are necessary to determine a possible synergistic interactionNel corso degli ultimi anni sono stati osservati gravi fenomeni di deperimento e morie di piante di melograno in vari impianti del Veneto. Vista l’assenza di informazioni sull’eziologia di queste fitopatie, è stata svolta un’indagine diagnostica con l’intento di isolare, identificare e caratterizzare i patogeni coinvolti. Dagli isolamenti effettuati su campioni di branche e rizosfera prelevati da 45 piante sintomatiche sono state ottenute complessivamente 88 colonie di specie fungine e di oomiceti, che sulla base dei caratteri morfologici e genetici (sequenze nucleotidiche dell’intera regione degli spaziatori interni trascritti ITS1 e ITS2) sono state suddivise in 8 gruppi appartenenti rispettivamente alle specie: Botryosphaeria dothidea e Neofusicoccum parvum (Botryosphaeriaceae), Diaporthe eres (Diaporthaceae), Coniella granati (Schizoparmaceae), Cytospora punicae (Valsaceae), Phytophthrora palmivora, P. pseudocryptogea e Phytopythium vexans (Peronosporaceae). Nei saggi di patogenicità, tutte le specie, ad eccezione di C. punicae, hanno riprodotto i sintomi della malattia osservati in campo, sebbene con un diverso grado di virulenza. I risultati ottenuti evidenziano la complessità eziologica dei fenomeni di disseccamento e moria di piante osservati nei melograneti dell’Italia nord-orientale. Ulteriori studi sono attualmente in corso per determinare eventuali interazioni sinergiche tra i patogeni riscontrati sulla chioma delle piante di melograno e quelli ad habitus radical