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Sistemi a punto fisso per la difesa del melo dalla ticchiolatura (Venturia inaequalis): primi risultati
No full textIn areas characterized by steep slopes and fragmentation of plots, such as hilly and mountainous zones, crop protection treatments are particularly burdensome. Alternatives to traditional equipment for the application of PPP are currently being evaluated, both in orchards and vineyards. Among these, fixed spray delivery systems (FSDS) have recently demonstrated that they can apply adequate quantities of PPP to the foliage and therefore guarantee the biological efficacy of treatments, while reducing spray drift. Based on these premises, two FSDS prototypes were tested in an apple orchard to evaluate their performance in the management of apple scab. The FSDS prototypes were compared to evaluate the differences in terms of biological efficacy of the treatments, also in comparison to a conventional air-assisted sprayer, as well as an untreated control. All plots were treated according to the same application program and dosage. The deposition of the spray in the foliage was also evaluated, using a mixture of water and tracer (Tartrazine E102). Tracer deposits were found to be generally lower for the FSDS prototypes compared to the sprayer. Despite this, the FSDS were able to guarantee the biological efficacy against apple sca
A DNA-free editing approach for viticulture sustainability: dual editing of DMR6-1 and DMR6-2 enhances resistance to downy mildew
Get PDFThe sustainability of viticulture hinges on maintaining quality and yield while reducing pesticide use. Promising strides in this direction involve the development of clones with enhanced disease tolerance, particularly through the knockout of plant susceptibility genes. Knocking out of Downy Mildew Resistant 6 (DMR6) led to increased levels of endogenous salicylic acid (SA), a regulator of immunity, resulting in enhanced tolerance to Downy Mildew (DM) and other diseases in various crops. Mutations in both DMR6-1 and DMR6-2 genes were introduced into two grapevine cultivars using CRISPR-Cas9 using two methods. In the first case, transgene delivery mediated by A. tumefaciens was employed, while in the second case, we developed a 'single-cell technology' for gene editing, creating non-transgenic grapevine mutants through the regeneration of protoplasts previously edited with the CRISPR/Cas9 ribonucleoprotein. We tested the susceptibility of single and double mutants to DM through artificial inoculation assays on detached leaves and whole plants. Our findings indicate that a simultaneous mutation in both DMR6-1 and DMR6-2 is needed to significantly enhance resistance to DM, with the double mutant (dmr6-1-dmr6-2) outperforming either single mutant in both cultivars. Elevated levels of endogenous SA were only observed in the double mutant, while single mutation in DMR6-1 or DMR6-2 proved ineffective. Collectively, our data highlight the need for a double knockout to achieve appreciable results against DM-susceptibility. Currenlty, we are adapting the 'single-cell technology' to generate edited vines from various agronomically relevant cultivars. In parallel, we are assessing the performance of plants edited in different susceptibility genes
Predizione della freschezza dei vegetali percepita dai consumatori mediante analisi sensoriale e strumentale
No full textThe global distribution and drivers of wood density and their impact on forest carbon stocks
Get PDFThe density of wood is a key indicator of the carbon investment strategies of trees, impacting productivity and carbon storage. Despite its importance, the global variation in wood density and its environmental controls remain poorly understood, preventing accurate predictions of global forest carbon stocks. Here we analyse information from 1.1 million forest inventory plots alongside wood density data from 10,703 tree species to create a spatially explicit understanding of the global wood density distribution and its drivers. Our findings reveal a pronounced latitudinal gradient, with wood in tropical forests being up to 30% denser than that in boreal forests. In both angiosperms and gymnosperms, hydrothermal conditions represented by annual mean temperature and soil moisture emerged as the primary factors influencing the variation in wood density globally. This indicates similar environmental filters and evolutionary adaptations among distinct plant groups, underscoring the essential role of abiotic factors in determining wood density in forest ecosystems. Additionally, our study highlights the prominent role of disturbance, such as human modification and fire risk, in influencing wood density at more local scales. Factoring in the spatial variation of wood density notably changes the estimates of forest carbon stocks, leading to differences of up to 21% within biomes. Therefore, our research contributes to a deeper understanding of terrestrial biomass distribution and how environmental changes and disturbances impact forest ecosystems
More than meets the eye: unraveling the interactions between skin microbiota and habitat in an opportunistic amphibian
Get PDFWith amphibians still holding the record as the most threatened class of terrestrial vertebrates, their skin microbiota has been shown to play a relevant role in their survival in a fast-changing world. Yet little is known about how abiotic factors associated with different aquatic habitats impact these skin microorganisms. Here we chose the yellow-bellied toad (Bombina variegata), a small anuran that colonizes a wide range of wetland habitats, to investigate how the diversity and composition of both its bacterial and fungal skin communities vary across different habitats and with water characteristics (temperature, pH, and dissolved oxygen) of these habitats. Skin microbiota was sampled from 14 sites in the Province of Trento (Italy), including natural pools, ephemeral ponds, irrigation tanks, and farm ponds. Interestingly, the diversity of the two microbial components was also highly correlated. Close associations between both the diversity and composition of water and skin communities were noted for each habitat and sampling site, suggesting that water bodies actively contribute to the skin microbiota assemblage. In addition, water pH, temperature, and dissolved oxygen affected both bacterial and fungal diversity of skin. We confirmed the presence of Batrachochytrium dendrobatidis in skin samples of animals collected from eight waterbodies, as well as more than 60 microbial taxa previously associated with resistance to this pathogen. We concluded that both skin bacterial and fungal communities appear to be influenced by each other as well as by environmental communities and conditions, and these relationships connecting the whole ecosystem should be considered in future research concerning amphibian conservation
Taxonomic and functional analysis of bacterial metagenomes and metagenome-assembled genomes from an Alpine Biosphere Reserve
No full textAlpine lakes, small water bodies, ponds and peat bogs are unique and ecologically significant freshwater habitats. These habitats play crucial roles in supporting regional biodiversity and biogeochemical cycles and provide essential ecosystem services, including carbon storage, decomposition of organic matter, and water filtration. Importantly, they support diverse microbial communities and often harbor rare and endangered species. Understanding the composition and functional potential of the bacterial communities residing in freshwater and sediment habitats of highly biodiverse areas is central for assessing and benchmarking ecosystem health and resilience, especially under ongoing climate change. The microbial biodiversity of the freshwater habitats in the ‘Alpi Ledrensi and Judicaria’ Biosphere Reserve has been previously described by Vettorazzo et al. (2024) utilizing metabarcoding analysis based on the V3-V4 regions of the 16S rRNA gene. Here, we employ full-shotgun metagenomics sequencing to i) gain increased taxonomic resolution of the bacterial communities of these habitats, ii) describe their ecological role by looking at their genomic functional potential and iii) compile a catalog of metagenome-assembled genomes (MAGs) to characterize rare bacterial species further. We confirm the high variability of the microbial communities along the physiographic gradient of the water bodies, with a marked difference in bacterial richness and composition between freshwater and sediment habitats. Moreover, by investigating the presence of genes related to the main biogeochemical metabolic pathways, we link community structure to ecosystem functions. A total of 485 high-quality bacterial MAGs were assembled from the sampled sites, of which 72% of species are novel (currently absent in curated bacterial databases such as GTDB, RS220). Most unknown species belonged to the Phyla Cyanobacteria (10 MAGs), Patescibacteria (23 MAGs), Verrucomicrobiota (25 MAGs), Bacteroidota (57 MAGs), Actinomycetota (75 MAGs) and Pseudomonadota (121 MAGs). Amongst the isolated MAGs, 76% were reconstructed from water habitats, while only 23% were from sediment habitats, reflecting the technical difficulties still present when assembling genomes de novo from highly biodiverse soil samples. The MAGs uncovered from these understudied environments contribute to widening the set of environmental reference genomes, thereby increasing the mappability of environmental metagenomes in future studies
A pond of knowledge: a multi-disciplinary perspective on amphibian conservation
Get PDFMentre il drammatico declino globale delle popolazioni di anfibi diviene sempre più allarmante, sorge la domanda se sia effettivamente possibile una convivenza sostenibile tra gli esseri umani e queste “bestie immonde e ripugnanti”. Nel tentativo di affrontare questa questione, questa tesi di dottorato si concentra sulla Provincia di Trento come caso di studio per indagare la presenza e il benessere delle comunità di anfibi all’interno di aree protette e siti artificiali e soggetti a impatto antropico, applicando diversi approcci molecolari e statistici, incluso un innovativo workflow multidisciplinare basato su metodi di pianificazione del paesaggio. Innanzitutto, ho sviluppato un nuovo protocollo non invasivo basato su campioni di DNA ambientale, testandolo sulla specie modello Rana temporaria. Da questo studio è emerso che il protocollo può essere utilizzato per ottenere informazioni sia sulla presenza delle specie che sulla loro diversità genetica, poiché ho dimostrato che gli indici standard di diversità genetica calcolati con questo approccio e con i metodi tradizionali sono fortemente correlati. In secondo luogo, ho quindi esteso questo protocollo a tutte le specie di anfibi nell'area di studio, testando il nuovo workflow sia sul campo, in una varietà di habitat naturali e artificiali, sia durante l'analisi bioinformatica, ottenendo con successo dati sugli aplotipi mitocondriali di dieci specie di anfibi. In terzo luogo, ho incluso questi dati di presenza di anfibi, insieme ad una serie di indici ecologici e paesaggistici che caratterizzano i siti considerati, in un approccio di analisi multidimensionale utilizzato in pianificazione del paesaggio. I primi risultati hanno evidenziato l’importante ruolo delle zone umide protette per la conservazione delle comunità di anfibi e hanno anche indicato le pozze d’alpeggio come potenziali ulteriori siti di riproduzione per gli anfibi. Infine, ho caratterizzato la composizione delle comunità cutanee sia batteriche che fungine nelle popolazioni di Bombina variegata da habitat con vari gradi di impatto antropico, dimostrando che queste comunità microbiche sono in effetti influenzate dalla presenza e dalle attività umane, seppur presentando pattern discordanti tra diversi indici di diversità (cioè, diversità alfa e beta). In conclusione, pur confermando l'influenza delle pressioni antropiche sulla presenza e sul benessere degli anfibi, questa tesi ha anche evidenziato l'esistenza di possibili habitat 'intermedi' dove la convivenza uomo-anfibi è possibile (ad esempio, le pozze d’alpeggio), nonché la necessità di integrare approcci provenienti da diverse discipline per ottenere un quadro di conservazione unificato mirato a uno sviluppo veramente sostenibile.As the dramatic decline of amphibian populations worldwide is becoming increasingly alarming, the question arises of whether a sustainable coexistence between humans and these ‘foul and loathsome beasts’ is possible at all. To address this issue, this doctoral thesis focuses on the Province of Trento as a case study to investigate the presence and wellbeing of amphibian communities in protected areas as well as artificial and human-impacted sites applying different molecular and statistical approaches, including an innovative multidisciplinary workflow based on landscape planning methods. First, I developed a new, non-invasive protocol based on environmental DNA samples, testing it on the model species Rana temporaria. This study proved that the new protocol can be used to obtain information on both species presence and genetic diversity, as I found that standard genetic diversity indices calculated with this approach strongly correlated with that estimated with traditional methods. Secondly, I therefore extended this innovative protocol to all amphibian species living in the study area, testing the new workflow both in the field, across a variety of natural and artificial habitats, and during bioinformatic analysis, successfully retrieving mitochondrial haplotype data of ten amphibian species. Thirdly, I included these amphibian presence data, along with a series of ecological and landscape indices characterizing the considered sites, into a multidimensional analysis approach derived from landscape planning theory. The first results of this study highlighted the important role of protected wetlands for amphibian communities’ conservation, and also indicated farm ponds as potential additional breeding sites for amphibians. Lastly, I characterized the composition of both bacterial and fungal skin communities in Bombina variegata populations from habitats with varying degrees of anthropogenic impact, showing that these microbial communities are indeed affected by human presence and activities, but showing discording patterns between different diversity indices (i.e., alpha and beta diversity). In conclusion, despite confirming the influence of anthropogenic pressures on presence and wellbeing of amphibians, this thesis also highlighted the existence of possible ‘intermediate’ habitats where human-amphibian cohabitation is possible (i.e., farm ponds), as well as the necessity of integrating approaches from different disciplines to achieve a unified conservation framework aimed at a truly sustainable developmen
