Giorgia Fedele

BACKGROUND: A multilevel meta‐analysis was conducted to provide further evidence on the benefits of decision tools (DTs) in crop protection for grapevines, potato, and wheat. Published data on disease severity, the Treatment Frequency Index (TFI; an index combining the number and dose of fungicide sprays), and crop yield (for potato and wheat only) in standard farmer‐ (ST) and DT‐based fungicide scheduling, compared with untreated controls (UTC), were collected through a systematic literature review. Experience‐based (EX) interventions were also included for grapevines, with treatments scheduled according to monitoring or crop phenology. The data set (516 comparisons) comprised substantial among‐study variability in disease severity. RESULT: In grapevine, DT and ST showed similar disease control, with >75% efficacy compared with UTC; DT significantly reduced TFI by 40% in both organic and integrated pest management systems compared with ST. Despite reduced TFI, EX provided significantly lower disease control than both ST and DT. In potato, ST showed significantly lower disease severity than DT (9.2% and 10.2% severity, respectively), corresponding to 52.4% and 45.8% efficacy. DT reduced TFI by 31% compared with ST, while maintaining a similar yield. In wheat, ST provided a slightly lower but significant disease severity than DT (18.0% and 19.8%, respectively), corresponding to 64.2% and 51.8% efficacy, respectively, compared with UTC. DT reduced TFI by 42% and yield by 3%. CONCLUSION: Our results showed that DTs can contribute to reducing fungicide dependence, although their performance can vary among crops. Farmers should be supported in the appropriate use of DTs to achieve more sustainable crop protection. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Certain agricultural practices may influence the susceptibility of the plant tissue to pathogens, including practices that influence the canopy density, which in turn may favor disease development through changes in the canopy microclimate. This relationship has previously been demonstrated for downy mildew (DM), caused by Plasmopara viticola , through comparisons of different trellising systems. In this work, we investigated the extent to which grapevine canopy density affects the susceptibility of leaves to P. viticola and the development of DM epidemics during the season in a single VSP system subjected to different canopy densities through modulating agronomic interventions, including variations in bud load, fertilization, and irrigation. Leaf susceptibility was investigated through artificial inoculation of P. viticola sporangia on leaf discs excised from the leaves of plants with different canopies. DM progress in the vineyard was periodically assessed as disease severity and then expressed as AUDPC. Infection on leaves from plants with denser canopies was more severe than that in leaves from plants with sparser canopies; however, neither changes in leaf predisposition to infection nor differences in microclimatic conditions (with higher moisture levels at nighttime in denser canopies) significantly affected DM progress in field. These findings confirm that DM epidemics are driven by complex interactions among host plant components, pathogen infection cycle, and microclimate factors. Although denser grapevine canopies increase the predisposition of leaves to P. viticola and enhance the moistness of the within-canopy microclimate, canopy density alone does not necessarily favor more severe epidemic development within uniform VSP systems.

Volatile organic compounds (VOCs) produced by Medicinal Aromatic Plants (MAPs) are bioactive signaling molecules that play key roles in plant defense, acting against pathogens and triggering resistance responses. Intercropping with VOC-emitting MAPs can therefore enhance disease resistance. This study investigated VOCs emitted by sage (Salvia officinalis) as potential resistance inducers in grapevine (Vitis vinifera) against Plasmopara viticola, the causal agent of downy mildew, under consociated growth conditions. Sage and grapevine plants were co-grown in an airtight box system for 24 or 48 h, after which grape leaves were inoculated with P. viticola. Disease assessments were integrated with grapevine leaf metabolic profiling to evaluate responses to VOC exposure and pathogen infection. Untargeted and targeted metabolomic analysis revealed that sage VOCs consistently reprogrammed grapevine secondary metabolism, without substantial differences between 24 and 48 h exposures. Lipids, phenylpropanoids, and terpenoids were markedly accumulated following VOC exposure and persisted following inoculation. Correspondingly, leaves pre-exposed to sage VOCs exhibited a significant reduction in disease susceptibility. Overall, our results suggest that exposure to sage VOCs induces signaling and metabolic reprogramming in grapevine. Further research should elucidate how grapevines perceive and integrate these signals, as well as the broader processes underlying MAP VOC-induced defense, and evaluate their translation into sustainable viticultural practices.

Walnut blight, caused by Xanthomonas arboricola pv. juglandis (Xaj), occurs worldwide in almost all areas where the Persian walnut (Juglans regia) is grown, causing significant reductions in nut yield via defoliation and fruit drop. The disease control relies on the calendar-based, repeated use of chemical bactericides, negatively impacting economic and environmental sustainability and potentially inducing Xaj resistance to chemicals. This study developed and validated a mechanistic model incorporating the main stages of the pathogen’s life cycle and the influence of weather under orchard conditions to improve the scheduling of disease control interventions. The model can simulate (i) the mobilization of primary inoculum; (ii) the infection caused by bacteria; and (iii) the lesion formation and production of secondary inoculum. We evaluated the model against 21 independent walnut blight epidemics in Italy (9 epidemics on leaves in five orchards) and the United States (12 epidemics on fruit in six orchards). Overall, the model provided accurate predictions for both the occurrence and nonoccurrence of infection, with a precision and F1-score of 0.866 and 0.844, respectively. The model could accurately predict disease progression across the season, with a concordance correlation coefficient between observed and predicted disease severities of 0.951, a root mean square error of 0.069, and a coefficient of residual mass of 0.024. After further validation, the model can serve as a decision-making tool for the risk-based timing of chemical sprays in walnut blight management.

Sour rot (SR) is a late‐season non‐Botrytis rot affecting grapevines, resulting from a complex interplay of microorganisms, including non‐ Saccharomyces yeasts and acetic acid bacteria. Nonmicrobial factors contributing to disease development encompass vectors (e.g., Drosophila spp.), the presence of wounds or microcracks on grape berry surfaces, and environmental conditions during berry ripening. The microbial complexes within SR‐affected grapes exhibit variability among different bioclimates and seasons, with certain microorganisms predominating under specific conditions. This study examined the influence of environmental conditions on the microbiome composition associated with SR‐affected grape bunches, utilising data from 41 locations across three distinct Italian bioclimates. We selected nine yeast and two bacterial species frequently isolated from sour‐rotted grapes for analysis. The growth responses of these microorganisms to temperature were assessed by categorising them into four ecophysiological clusters. Furthermore, we analysed the distribution of these microorganisms and their respective ecophysiological clusters across the three bioclimates. The results indicate that the microbiomes involved in SR can vary according to the bioclimatic conditions of the grape‐growing area. Further research is required to comprehend the ecological requirements of these microorganisms, define their ecological niches to understand their geographical distribution and epidemiology, and enhance SR management strategies.

Background: Mating disruption (MD) is a worthwhile technique for the control of Lobesia botrana and Eupoecilia ambiguella in central Europe and Mediterranean areas. MD efficacy is affected by the pheromone release (PR), which in turn is influenced by environmental conditions. Methods: The effect of weather conditions on PR was evaluated under four different fields in northern Italy. The PR of two commercial types of MD passive dispensers was correlated with different variables. Results: For both dispensers, the temperature and vapor pressure deficit explained PR in vineyards with diverse weather conditions better than time. The effect of temperature was not linear, and any temperature increase at high temperatures accelerated the PRR more than proportionally. One dispenser type showed a non-linear release trend of the pheromone emission in field conditions with respect to the considered variables; further, the stepwise regression pointed out the importance of the dichotomous variable associated with the vineyard for increasing the goodness-of-fit. Conclusions: The equations developed in this work are dispenser-dependent and can provide information on the PR during the season for each dispenser type, as influenced by weather conditions. These equations could serve as an input for a pheromone concentration model to predict concentrations based on meteorological conditions.

Sour rot (SR) is a grapevine disease complex that is not completely understood in its etiology and epidemiology. Recently, SR has received special attention due to its increasing economic importance due to crop losses and reduced wine quality. In this study, the fungal and bacterial microbiota of healthy (i.e., without rot symptoms) and rotten (i.e., exhibiting visual and olfactory SR symptoms) ripe bunches were characterized across 47 epidemics (39 vineyards in six Italian grape-growing areas) over three years. The 16S rRNA gene, ITS high-throughput amplicon sequencing, and quantitative PCR were used to assess the relative abundance and dynamic changes of microorganisms associated with SR. The estimators of genera richness of fungal communities within samples indicated a significantly different diversity between healthy and rotten bunches. For bacterial communities, the healthy and rotten bunches significantly differed in the total number of species, but not in abundance distribution across species. The bunch status (i.e., healthy and rotten) was a significant source of diversity (p < 0.01) when the community composition between samples was evaluated, indicating that microbiome composition varied between healthy and rotten bunches. In particular, healthy and rotten bunches shared 43.1 and 54.8% of fungal and bacterial genera, respectively; 31.3% (fungal) and 26.2% (bacterial) genera were associated with rotten bunches only. The yeast genera Zygosaccharomyces, Zygoascus, Saccharomycopsis, Issatchenkia, and Pichia and the bacterial genera Orbus, Gluconobacter, Komagataeibacter, Gluconacetobacter, and Wolbachia were strongly associated with bunches showing SR symptoms based on a linear discriminant analysis. These microorganisms have been associated with Drosophila insects in literature. The relationships between the microflora associated with SR-affected bunches and the roles of Drosophila in SR development need further investigation, which may open perspectives for more effective disease control.

Sour rot (SR) is a disease complex that affects grape berries during ripening and can cause severe yield losses and deterioration of wine quality. The etiology and epidemiology of the disease remain uncertain, which has severely limited the development of specific, targeted management strategies. In this study, a network meta-analysis was applied to data collected through a previous systematic literature review for statistically comparing the efficacy of different methods for the control of SR and some filamentous fungi isolated from rotten berries. Use of either synthetic fungicides (CHEM) and natural compounds or biocontrol microorganisms (BIO) provided partial and variable control of SR; however, the efficacy of BIO was similar to, or higher than, that provided by CHEM. Agronomic practices (AGRO) had a significant but lower effect on SR. The integration of different control methods (IPM) provided better and less variable disease control than any single method. Natural compounds, such as zeolites and bicarbonates, and microorganisms (e.g., yeasts Candida and Aureobasidium) are also promising alternatives to synthetic fungicides in SR control.

Sour rot (SR) is one of the major diseases affecting grapevine berries, causing severe yield losses and deterioration of wine quality. SR is caused by an etiologic complex of microorganisms, including yeasts, bacteria, and filamentous fungi. This systematic review focuses on the etiology, epidemiology, and control of SR. A total of 74 papers published between 1986 and 2023 were assessed in this review. Description of disease symptoms was quite consistent across the papers, including oxidation of the grape skin, disaggregation of the internal tissues, and detachment of the rotten berries from the pedicel. The affected bunches are characterized by the smell of acetic acid and ethyl acetate that attracts fruit flies (Drosophila spp.). However, several knowledge gaps and/or inconsistencies were identified with respect to SR etiology, epidemiology, and control. Overall, 146 microorganisms were isolated from the affected berries (44.5% yeasts, 34.3% bacteria, and 21.2% filamentous fungi); however, the selected papers could not definitively clarify which species are primarily involved in the etiology of the disease. A general inconsistency was also observed in the methods used to assess the incidence and severity of SR in vineyards, making inter-study comparisons extremely challenging. Inconsistencies were also found in the methods used for pathogenicity assessment in artificial inoculation studies. Furthermore, gaps were detected in terms of SR epidemiology, with a focus on environmental conditions affecting the disease development. The SR management options are limited, and efficacy trials often result in poor, variable, and inconsistent levels of control, which might be attributed to the lack of knowledge on disease epidemiology. These knowledge gaps and inconsistencies were analyzed in this review to inform future research activities.

BACKGROUND: Biocontrol agents (BCAs) are alternatives to synthetic fungicides with low risk to the environment and human health. Although several studies on the biocontrol of gray mold in vineyards have been performed, it is necessary to improve the usage of BCAs in fields conditions. Therefore, in the present study, BCAs were used both in calendar‐based [based on four growth stages (GSs), i.e., flowering, pre‐bunch closure, veraison, and before harvest] and predictive model‐based strategies (only when Botrytis cinerea infection risk was predicted by the model). The BCAs applied during the seasons were selected considering the grapevine GSs. Treatments performed with BCAs were compared with synthetic fungicide treatments and an untreated control. The trials were conducted in three experimental vineyards with four epidemics. To evaluate the level of gray mold control of each treatment, disease severity was assessed at harvest and the presence of latent infection was evaluated.RESULTS: The integrative use of the predictive model and BCAs provided satisfactory levels of gray mold control, with gray mold severity levels significantly lower (P < 0.001) than those of the untreated control, which had severity values (< 7%) similar to those observed with synthetic fungicides following both calendar and model‐based strategies.CONCLUSIONS: The integrative use of the predictive model and BCAs represents a valid alternative to conventional methods of gray mold control in vineyards, with more than 75% reduction in fungicide usage. © 2024 Society of Chemical Industry.