The survival of Quercus species in the Mediterranean region is challenged by root diseases caused by Phytophthora cinnamomi Rands and Pythium spiculum Paul, as well as by drought. This study aimed to examine the interaction between both pathogens under varying soil moisture levels. Seedlings were inoculated with P. cinnamomi, Py. spiculum, or both, and exposed to soil moisture conditions ranging from saturation to drought. Results showed that P. cinnamomi caused high levels of root necrosis in saturated-to-moderately dry soils, but it was unable to cause infection under drought conditions. Conversely, Py. spiculum infected roots under drought but not under saturation conditions and was less virulent in wet soils compared to P. cinnamomi. In seedlings inoculated with both pathogens, symptoms were similar to those induced by P. cinnamomi alone, without any synergistic effect. This study highlights that P. cinnamomi and Py. spiculum infect oak roots across a range of soil moistures, with P. cinnamomi being the predominant pathogen in wet-to-moderately dry soils, and Py. spiculum being the predominant pathogen in droughted soils. Under current and projected future water deficit conditions, oak woodlands infected by both pathogens face a significant threat to their survival.
The common fig (Ficus carica L.) is susceptible to mycotoxin contamination, raising food safety concerns given the strict maximum levels for aflatoxins (AF) and ochratoxin A (OTA) established by Regulation (EU) 2023/915 for dried figs. We characterized the susceptibility of three commercially relevant cultivars from the Jerte Valley (‘Calabacita’, ‘Cuello Dama Blanco’, and ‘Granito’) to Aspergillus section Flavi colonization under controlled and orchard conditions. These findings were integrated with an industry surveillance dataset (2014–2023; 326 batches), with cultivar comparisons restricted to the comparable period 2020–2023 (184 batches), from a local fig-processing cooperative. Under controlled inoculation, ‘Calabacita’ consistently showed the highest internal colonization and proportion of figs colonized, whereas ‘Granito’ showed the lowest values. Sealing the ostiole reduced colonization across cultivars and abolished cultivar differences, thereby supporting the ostiole as the primary entry route. Fruit susceptibility increased with fruit size across all three cultivars. Dry conidial inoculation, emulating natural airborne spread, resulted in substantially higher colonization than inoculation with an aqueous conidial suspension, both in severity (100% vs. 3.7%) and incidence (100% vs. 7.3%). Orchard assays were consistent with the controlled inoculation results: ‘Calabacita’ showed higher section Flavi colonization than ‘Cuello Dama Blanco’ and ‘Granito’, which did not differ from each other. Fruit position did not affect colonization by section Flavi, but it significantly affected colonization by section Nigri, which was higher in dropped fruits across cultivars. AF-OTA co-occurrence was restricted to ‘Granito’ (3 batches; 2.6%) and was absent in ‘Calabacita’. Surveillance data (2020–2023) were consistent with the experimental findings. ‘Calabacita’ showed predominantly AF-related non-compliance (with AFB1 and AFTA exceedances reaching 25.7%), whereas ‘Granito’ showed higher OTA exceedance (10.5% vs. 1.4%), reflecting distinct contamination profiles between cultivars. This study informs AF and OTA management strategies in dried figs based on cultivar susceptibility profiling, prescreening systems prior to commercialization, and reduction in fruit–soil contact during drying.