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Spatio-temporal variability of isotopic and chemical tracers in high-elevation water sources, Eastern European Alps
No full textIn high-mountain areas, the ratios of stable water isotopes (δ18O, δ2H) and solute concentrations are often used to infer the relative contribution from snow, ice, and rain waters to runoff. Yet, the strong spatial and temporal tracer variability of these hydrological resources is often overlooked. We characterised the water isotopes and chemistry of hydrological resources in two headwater catchments of South Tyrol (Eastern Italian Alps). During the melt season of 2022 and 2023, we collected bi-weekly water samples from precipitation, snow, snowmelt, as well as ice and runoff on the surface of a small glacier and within the debris of two rock glaciers. We found a sharp isotopic seasonality in snowmelt and precipitation, and a tendency of depletion and fractionation with increasing elevation in both resources. End-member mixing models identified permafrost and glacial ice as the dominant components (over rainwater and snowmelt) of the rock glacier and glacier runoff, respectively. Both runoff types had elevated concentrations of sulphate and trace elements (Sr, Ba, Al, Mn, Ni, Co, Fe, Zn, Li, Y). This is attributed to the intense chemical weathering occurring on abundant freshly ground rock particles on the glacier, and to the melt of solute-enriched perennial ice in rock glaciers. While deep water pathways are generally considered as major locations of chemical reactions, we highlight that even the surface runoff of glaciers and rock glaciers can strongly contribute to the export of toxic elements – e.g. Ni – to aquatic ecosystems. This has important implications for drinking water and environmental qualit
Valutazione del potenziale impatto subletale di insetticidi sui principali tratti comportamentali e fisiologici di Aphidius colemani Viereck (Hymenoptera: Braconidae)
Get PDFFirst complete mitogenome assembly of Castanea sativa: structure, comparative genomics, and phylogeny
No full textThe sweet chestnut (Castanea sativa Mill.) is one of the most widespread cultivated temperate trees in Europe, valued both for its edible nuts and high-quality timber. Due to its ecological, economic, and cultural importance, it has been the focus of extensive genetic studies. However, its mitochondrial genome has remained largely unexplored. Here, we present the first complete mitochondrial genome of C. sativa (cultivar ‘Marrone di Chiusa Pesio’), assembled using high-throughput sequencing and characterised through comparative analyses with closely related species. The final assembly consists of six contigs with a total length of 402,729 bp, comprising 35 protein-coding genes, 33 tRNA genes, and 3 rRNA genes. Compared to the congeneric C. mollissima, C. sativa shows a relatively low repeat content in terms of both number and length. Codon usage patterns were found to be highly similar among C. sativa, C. mollissima, and C. henryi. Additionally, homologous fragments between the plastid and mitochondrial genomes were identified, totaling 4,671 bp (1.16% of the mitogenome), and including several tRNA genes. A phylogenetic analysis based on mitochondrial coding sequences from C. sativa and 11 other Fagaceae species confirmed its close relationship with C. mollissima, C. henryi, and Castanopsis carlesii. Discrepancies observed among mitochondrial, plastid, and nuclear gene trees likely reflect either inherent genomic characteristics or extensive hybridisation, particularly within the genus Quercus
Mycorrhizal symbioses and tree diversity in global forest communities
Get PDFUnraveling the mechanisms underlying the maintenance of species diversity is a central pursuit in ecology. It has been hypothesized that ectomycorrhizal (EcM) in contrast to arbuscular mycorrhizal fungi can reduce tree species diversity in local communities, which remains to be tested at the global scale. To address this gap, we analyzed global forest inventory data and revealed that the relationship between tree species richness and EcM tree proportion varied along environmental gradients. Specifically, the relationship is more negative at low latitudes and in moist conditions but is unimodal at high latitudes and in arid conditions. The negative association of EcM tree proportion on species diversity at low latitudes and in humid conditions is likely due to more negative plant-soil microbial interactions in these regions. These findings extend our knowledge on the mechanisms shaping global patterns in plant species diversity from a belowground vie
Impact of post-harvest apple scab on peel microbiota, fermentation dynamics, and the volatile/non-volatile composition of cider
Get PDFApple scab is a disease caused by Venturia inaequalis; it alters the vegetative cycle of apple trees and affects the fruits in orchards or during post-harvest storage. Utilizing rotten apples in cidermaking is a promising technique to mitigate crop losses; nonetheless, uncertainties persist regarding the beneficial effects of damaged fruits. This study involves a thorough chemical analysis of cider produced from both healthy and scab-infected fruits to identify compositional changes caused by microbial proliferation and to assess their impact on cider quality. Apples infected by post-harvest apple scab, as opposed to uninfected apples, were employed in cidermaking. The peel microbiota was described by plate count, and next-generation sequencing-based metabarcoding methods were used to describe the peel microbiota, while HPLC and GC MS-MS were used to characterize the cider compositions. Apples infected with post-harvest scab host a specific fungal consortium with higher biodiversity, as evidenced by the Shannon evenness index, especially in the fungi kingdom. The presence of apple scab slows fermentation by up to 23%, lowers ethanol accumulation by up to 0.4%, and affects certain cider constituents: sugars, alcohols, amino acids, fatty acids, and esters. The statistical treatment of data relative to the chemical profile (PLS and PCA on the 31 compounds with VIP > 1) distinguishes ciders made from altered or safe fruits. Scab-infected apples can be valorized in the agri-food industry; however, microbiota alterations must not be underestimated. It is necessary to implement adequate mitigation strategie
Coupling of temporal-check-all-that-apply and nose-space analysis to investigate the in vivo flavor perception of extra virgin olive oil and carriers’ impact
Get PDFThe perceived quality of extra virgin olive oil (EVOO) arises from the multisensory integration of multimodal stimuli, primarily driven by non-volatile and volatile organic compounds (VOCs). Given that EVOO is frequently consumed in combination with other foods, cross-modal interactions, encompassing both internal and external elements, play a crucial role in shaping its sensory perception. A more realistic representation of EVOO perception can be achieved by considering these cross-modal effects and their temporal dynamics. This study employed dynamic sensory and instrumental techniques to investigate the product-related mechanisms that influence EVOO flavor perception. Ten trained panelists (mean age = 41.5 years; 50% female) evaluated two EVOO samples under two consumption conditions: alone and accompanied by a solid carrier (bread or chickpeas). Temporal Check-All-That-Apply (TCATA) and nose-space analysis using Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) were conducted simultaneously. Sensory descriptors and mass spectral peaks were analyzed through temporal curve indices (Area Under the Curve, Maximum Citation/Concentration, Time to Maximum), which were then used to construct multi-dimensional sensory and VOC release maps. Findings revealed that the composition and texture of the food carriers had a greater influence on temporal flavor perception than the variability in VOCs released by the different EVOO samples. These results underscore the importance of considering cross-modal sensory interactions when predicting EVOO flavor perception. The carriers modulated both the perception and VOC release, with effects dependent on their specific composition and texture. This methodological approach enabled a deeper understanding of the dynamic relationship between VOC release and EVOO sensory experienc
Advanced LC-IMS-MS protocol for holistic metabolite analysis in wine and grape samples
No full textThe final aim of metabolomics is the comprehensive and holistic study of the metabolome in biological samples. Therefore, the use of instruments that enable the analysis of metabolites belonging to various chemical classes in a wide range of concentrations is essential, without compromising on robustness, resolution, sensitivity, specificity, and metabolite annotation. These characteristics are crucial for the analysis of very complex samples, such as wine, whose metabolome is the result of the sum of metabolites derived from grapes, yeast(s), bacteria(s), and chemical or physical modification during winemaking. In recent years, a big advantage, in this direction, was the hardware developments on hyphenated instruments that enable the integration of liquid chromatography (LC), ion mobility spectrometry (IMS), and mass spectrometry (MS). This chapter describes an LC-IMS-MS protocol for the analysis of wine and grape samples as well as the use of IMS data in metabolite annotatio
Temporal changes in tick-borne pathogens prevalence observed in questing Ixodes ricinus (Linnaeus, 1758) across different habitat types in north-eastern Italian Alps
No full textChanges in land use, climate, and host community lead to increased complexity in ecoepidemiological relationships and zoonotic emergence. This study investigates the changes in the prevalence of Ixodes ricinus-transmitted pathogens in questing ticks over a 10-year interval in natural and agricultural habitats of the Autonomous Province of Trento (North-eastern Alps). We investigated three study sites classified as natural and agricultural by collecting questing ticks in 2011-2013, 2020 by tick-dragging along 100 m transects. The collected ticks were morphologically identified, while bacteria and protozoa were detected using PCR-based methods combined with sequencing. We investigated the effect of habitat type, tick stage and year on the proportion of infected ticks by using Generalized Linear Models (GLMs) and Two Proportion Z-test. In total 2652 ticks belonging to I. ricinus were collected and analysed. We found an overall prevalence of 27.1% in the study area, referred to Borrelia spp. (21.1%), Rickettsia spp. (8.4%) Anaplasma phagocytophilum (1.6%) and Babesia spp. (0.4%). We reported the circulation of 11 different zoonotic pathogen species, with varying infection rates across different years and habitats. In 2020, A. phagocytophilum, associated with agricultural habitats decreased, while Babesia spp. was found in all habitats. Among Borrelia burgdorferi s.l. complex, only B. burgdorferi s.s. and B. lusitaniae showed significant relationships in natural habitats, increasing in 2020. Rickettsia spp. did not show any significant habitat preference. Co-infections were identified in 8% of positivetested ticks with different spatio-temporal associations, primarily in natural settings. Our results provide new evidences that the risk of infection with tick-borne pathogens in the Alpine region varies over time and in different environments, broadening the current information on coinfection rates and circulation of zoonotic pathogens, previously not reported in this area
Towards the geographical traceability of the Italian walnut: a case study based on stable isotopes signatures (δ2 H, δ18O, δ13C, δ15N, δ34S) and elemental fingerprinting
No full textJuglans regia (L.) is cultivated worldwide for its nutrient-rich nuts. Italy is among the top five importing countries of walnuts in shell due to the strong decline in the Italian walnuts production in the early seventies, combined to a constantly growing demand. The current context is therefore favourable to promote the development of a local high-quality Italian walnut production. In this respect, tools capable of tracing the origin of walnut can support the process of valorisation and promotion of this product. The main aim of this study was to investigate to what extent stable isotope data (H, O, C determined in the lipid and defatted fractions, N and S of the defatted fraction) coupled with 56-element profiles could be used to differentiate Italian walnuts on a regional and global level. A total of 122 walnut samples from six countries and two years of harvest were analysed. Multivariate data analysis (JIVE) suggested a strong effect of the geographical origin, particularly at the regional level. However, it was not possible to completely exclude the effect of the harvest year on the overall variability of the samples. A preliminary analysis focussing on a regional scale (Italian samples only) and on a few samples of international origin, confirmed that the proposed approach could be potentially applied for the discrimination of Italian walnuts. Overall, the results presented support the effectiveness of stable isotopes and multi-element analyses in walnut traceability and local origin protection
The arthropod’s guide to European vineyards: invasive pests as hitchhikers of globalization
Get PDFInsects and mites are among the most widespread and economically significant invasive species worldwide due to their rapid reproduction, high dispersal ability, and capability to survive and quickly adapt to different environmental conditions and food sources. Increased globalization, i.e., increased human transportation and trade, is the main driver behind arthropod invasions. Globally, the spread of invasive arthropods represents a growing problem for agriculture, as many of these species are devastating pests, including vectors of plant pathogens. This is particularly relevant for perennial crops such as grapevine. Grapevine is a global crop that is susceptible to a range of aggressive pathogens and pests and, accordingly, one of the crops most frequently treated with pesticides in Europe. This review focuses on invasive insect and mite pests damaging European grapevine through feeding or vectoring pathogens. A comprehensive overview of present and potential future invasive arthropods threatening European viticulture is provided. Primary entry pathways of invasive grapevine pests into the EU, as well as their spread are discussed. The pest geographic origin and current distribution within the EU revealed particularly vulnerable regions. In the final section, lessons learned and future challenges are highlighted, along with sustainable monitoring and management options aimed to minimize the risk of introductions, and in turn pesticide application