Role of environmental and stand factors on forest dieback: An approach using structural equation modelling and machine learning

Forest Ecology and Management, Journal Year: 2024, Volume and Issue: 562, P. 121927 - 121927

Published: April 30, 2024

Language: Английский

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Diversity and Distribution of Phytophthora Species Along an Elevation Gradient in Natural and Semi-Natural Forest Ecosystems in Portugal

Pathogens, Journal Year: 2025, Volume and Issue: 14(1), P. 103 - 103

Published: Jan. 20, 2025

Globally, forests are constantly threatened by a plethora of disturbances natural and anthropogenic origin, such as climate change, forest fires, urbanization, pollution. Besides the most common stressors, during last few years, Portuguese have been impacted severe decline phenomena caused invasive pathogens, many which belong to genus Phytophthora. The Phytophthora includes large number species that invading ecosystems worldwide, chiefly consequence global trade human activities. This paper reports results survey diversity in semi-natural Portugal along an elevation gradient. Isolations performed from 138 symptomatic plant tissues rhizosphere samples collected 26 yielded total 19 belonging 6 phylogenetic clades, including P. cinnamomi (36 isolates), multivora (20), plurivora (9), cactorum (8), lacustris pseudocryptogea amnicola (6), hedraiandra pseudosyringae (5), thermophila bilorbang (4), inundata asparagi (3), citricola gonapodyides rosacearum chlamydospora (2), pachypleura syringae (1). Overall, data obtained highlight widespread occurrence sea level mountain habitats. pathogenicity tests carried out on 2-year-old chestnut plants confirmed key role recrudescence ink disease additional risk posed pachypleura, plurivora, forests. Finally, three species, citricola, hedraiandra, reported for first time Portugal.

Language: Английский

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Did ash (Fraxinus) become extinct on Cyprus?

Review of Palaeobotany and Palynology, Journal Year: 2025, Volume and Issue: unknown, P. 105286 - 105286

Published: Jan. 1, 2025

Language: Английский

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Morphological, Molecular and Pathological Characterization of Phytophthora pseudocryptogea Associated with Rosmarinus officinalis Dieback in Tuscany, Central Italy

Microorganisms, Journal Year: 2025, Volume and Issue: 13(3), P. 567 - 567

Published: March 3, 2025

A severe dieback of rosemary (Rosmarinus officinalis L.) plants was observed in a medicinal/culinary herb plantation Casole d’Elsa, Siena, central Italy. Symptoms included stunted growth, crown desiccation, root rot, collar rot and internal tissue necrosis, strongly indicative Phytophthora syndrome. Morphological molecular identification (ITS Cox1 sequencing) strains isolated from symptomatic stems, roots soil revealed the occurrence two species: pseudocryptogea, which constituted 94% isolates obtained stem, apparatus rhizosphere; megasperma, not recovered plant organs or tissue, being exclusively rhizosphere samples at low isolation rate (6%). The pathogenicity assessed by inoculating eighteen-month-old R. infestation trial. Plants inoculated with P. pseudocryptogea died 10 days after artificial inoculation. subsequently re-isolated inoculated, plants, thus fulfilling Koch’s postulates. megasperma were good vegetative condition did show any visible symptoms, suggesting to be nonpathogenic. Artificial inoculation tests confirmed aetiological agent responsible for death under study. This is first report root, caused on There evidence that poorly drained soils climate constraints facilitate spread this oomycete. These findings highlight critical role nursery trade introduction species agroecosystems emphasize need more stringent control measures.

Language: Английский

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Detection of Paecilomyces formosus associated with declining urban forests and beetles in Iran

Physiological and Molecular Plant Pathology, Journal Year: 2024, Volume and Issue: 133, P. 102384 - 102384

Published: Aug. 26, 2024

Language: Английский

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Morphological, physiological, molecular, and pathogenic insights into the characterization of Phytophthora polonica from a novel host, hazelnut (Corylus avellana)

Physiological and Molecular Plant Pathology, Journal Year: 2024, Volume and Issue: 131, P. 102292 - 102292

Published: April 25, 2024

Language: Английский

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RNAi-biofungicides: a quantum leap for tree fungal pathogen management

Critical Reviews in Biotechnology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 28

Published: Dec. 8, 2024

Fungal diseases threaten the forest ecosystem, impacting tree health, productivity, and biodiversity. Conventional approaches to combating diseases, such as biological control or fungicides, often reach limits regarding efficacy, resistance, non-target organisms, environmental impact, enforcing alternative approaches. From an ecological standpoint, RNA interference (RNAi) mediated double-stranded (dsRNA)-based strategy can effectively manage fungal pathogens. The RNAi approach explicitly targets suppresses gene expression through a conserved regulatory mechanism. Recently, it has evolved be effective tool in promoting sustainable management bio-fungicides provide efficient eco-friendly disease alternatives using species-specific targeting, minimizing off-target effects. With accessible data on outbreaks, genomic resources, delivery systems, RNAi-based biofungicides promising for managing pathogens forests. However, concerns fate of molecules their potential impact organisms require extensive investigation case-to-case basis. current review critically evaluates feasibility against by delving into methods, persistence, aspects, cost-effectiveness, community acceptance, plausible future protection products.

Language: Английский

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Pathogenicity of Botryosphaeriaceae and Phytophthora species associated with Paulownia dieback, canker and root rot in Italy

Phytopathologia Mediterranea, Journal Year: 2023, Volume and Issue: 62(3), P. 481 - 488

Published: Dec. 30, 2023

In recent years, an unusual decline and mortality has been observed in Paulownia plantations throughout the Marche region (Central Italy). Given economic importance of this emerging forest crop, a study was conducted to determine which pathogens are directly involved syndrome. Field surveys performed two revealed widespread occurrence severe disease symptoms such as leaf chlorosis, crown thinning, shoot branch dieback, sunken cankers, epicormic shoots root rot. Disease incidence also assessed by aerial remote sensing (RS) technologies using drones. Symptomatic samples collected from both stem tissues yielded fungal fungal-like colonies representing distinct families: Botryosphaeriaceae Peronosporaceae. Morphological DNA sequence data five species, identified Macrophomina phaseolina Botryosphaeria dothidea (Botryosphaeriaceae), Phytophthora pseudocryptogea, P. citrophthora erythroseptica (Peronosporaceae). that all species reported here for first time on Paulownia, Koch’s postulates were satisfied inoculating three at collar potted 1-year-old rooted cuttings June 2023. Thirty days after inoculation, plants showed same those field.

Language: Английский

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The Importance of Stand Structure in Narrow-Leaved Ash (Fraxinus angustifolia Vahl) Dieback—Insights from an Extensively Managed Stand on a Humogley Soil in Serbia

Forests, Journal Year: 2024, Volume and Issue: 16(1), P. 36 - 36

Published: Dec. 28, 2024

Ash dieback is a major issue affecting European ash populations, including narrow-leaved (Fraxinus angustifolia Vahl). An important factor contributing to the decline of fungal disease caused by Hymenoscyphus fraxineus. However, mortality trees also depends on stand structure that may influence dynamics. In 2020, we analysed middle-aged, extensively managed, stands growing Humogley soil (Cariceto remotae-Fraxinetum angustifoliae, Jov., et Tom. 1979). This permanent sample plot located in Posavina (Serbia), where observed reduced tree vitality and mortality. The originates from natural regeneration after succession marsh habitats. At ages 20–25 years (1996) 30–35 (2006), selective thinning was carried out. Until age 45–50 (2020), left unthinned, presence fungus recorded Serbia. measured diameter at breast height (DBH) each assessed their crown class degree isolation. These parameters were evaluated relation defoliation trees. results indicate manifest conditions strongly expressed intraspecific competition stand, particularly during stem exclusion stage. Healthy primarily within predominant/dominant exhibited highest mean DBH. Trees classified as dead or dying (81%–100% defoliation) had lower DBH compared both healthy (<25% significantly defoliated (26%–80%). level trees, suggesting linked poor growth.

Language: Английский

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Botryosphaeriaceae Species Associated with Stem Canker, Shoot Blight and Dieback of Fraxinus ornus in Italy

Forests, Journal Year: 2023, Volume and Issue: 15(1), P. 51 - 51

Published: Dec. 26, 2023

A severe dieback of flowering ash (Fraxinus ornus L.) has been observed in north-central Italy the last decades. Symptoms include typical sunken, light-brown cankers on stem and branches; vascular discoloration; tip shoot dieback; foliage necroses. The disease was more evident at beginning growing season, young regeneration. Six Botryosphaeriaceae species were consistently isolated from symptomatic plant tissues: Botryosphaeria dothidea, Diplodia fraxini, subglobosa, Dothiorella iberica, omnivora Neofusicoccum parvum. B. dothidea D. fraxini expressed higher aggressiveness showed a widespread incidence, being most frequently associated with cankers; other four less virulent erratic, occurring mainly succulent branch tips foliage. Isolates characterized using morphological molecular approaches (colony/conidial phenotyping rDNA-ITS genotyping). Phylogenetic analysis provided congruent phylogenies depicting relationships six taxa closely related conspecifics. Pathogenicity tests 2-year-old seedlings confirmed virulence fraxini. Extensive, multi-year field surveys different sites supported hypothesis that climatic vagaries, heat, water drought stresses, impaired tree health vigor, facilitating infection pervasive colonization by these species. Environmental stressors are thus key factor bringing fungal pathogens together multitrophic interaction F. novel, lethal fashion.

Language: Английский

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