1. Diversity of phytophthora species involved in new diseases of mountain vegetation in Europe with the description of phytophthora pseudogregata sp. nov.Carlo Bregant, Giovanni Rossetto, Letizia Meli, Nicolò Sasso, Lucio Montecchio, Ana Brglez, Barbara Piškur, Nikica Ogris, Lucia Maddau, Benedetto Teodoro Linaldeddu, 2023, izvirni znanstveni članek Povzetek: New and emerging Phytophthora-related diseases in small trees, shrubs and herbaceous plants typical of subalpine vegetation have recently been observed in Italy and Slovenia. Diseased plants showed a complex symptomatology including foliar necrosis, fruit rot, shoot blight and branch bleeding cankers. Since little information is available about the aetiology of these aerial Phytophthora diseases, from 2019 to 2022, field surveys were conducted in 54 sites to define the occurrence, distribution and impact of the Phytophthora species on mountain vegetation. A total of 360 Phytophthora isolates were obtained from 397 samples collected from 33 herbaceous and woody host species. Based on phylogenetic analysis and morphometric data, 17 Phytophthora species were identified: P. pseudosyringae (201 isolates), P. plurivora (54), P. gonapodyides (21), P. ilicis (20), P. alpina (17), P. acerina (11), P. cactorum (7), P. pseudocryptogea (6), P. cambivora (5), P. idaei (4), P. psychrophila (3), P. bilorbang (2), P. chlamydospora (2), P. hedraiandra (1), P. kelmanii (1), P. rosacearum (1) and P. syringae (1). In addition, three isolates of a new putative Phytophthora species obtained from Alnus viridis, Juniperus communis and Rhododendron ferrugineum are described here as Phytophthora pseudogregata sp. nov. Overall, the results highlighted an unexpectedly high diversity of Phytophthora species in mountain areas, with many species able to cause aerial infections due to the production of caducous sporangia. Ključne besede: alpine regions, emerging disease, oomycetes, foliar necrosis, ITS clade 6, phylogeny Objavljeno v DiRROS: 01.08.2023; Ogledov: 498; Prenosov: 371
Celotno besedilo (6,74 MB) Gradivo ima več datotek! Več... |
2. First report of Diplodia fraxini and Diplodia subglobosa causing canker and dieback of Fraxinus excelsior in SloveniaBenedetto Teodoro Linaldeddu, Carlo Bregant, Lucio Montecchio, Ana Brglez, Barbara Piškur, Nikica Ogris, 2022, drugi znanstveni članki Povzetek: 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. Ključne besede: emerging disease, invasive species, Botryosphaeriaceae, pathogenicity Objavljeno v DiRROS: 15.09.2022; Ogledov: 615; Prenosov: 297
Celotno besedilo (851,52 KB) Gradivo ima več datotek! Več... |