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- Host plant‐specific volatiles of Beauveria bassiana‐colonized plants initiate trophic plant–aphid–predator cascadesPublication . Cuenca‐Medina, María; Rodríguez Solana, Raquel; Moreno‐Rojas, José Manuel; Alcalá‐Herrera, Rafael; Quesada‐Moraga, Enrique; González‐Mas, NataliaBACKGROUND: Entomopathogenic ascomycetes (EAs) have efficacy in insect pest control through direct contact and indirectly as plant endophytes. As endophytes, they lead indirectly to pest mortality, enhance plant resilience to stresses, promote plant growth and alter plant volatile emissions. These changes can influence plant interactions with beneficial fauna, such as predators, parasitoids and pollinators. However, variation in endophytic colonization across plant species and EA strains raises questions about cultivar-specific responses within the same crop species. Here we evaluated the impact of endophytic colonization by the EA Beauveria bassiana on the volatile organic compounds (VOCs) of three melon cultivars: ‘Galia’, ‘Futuro’ and ‘Rinconete’. RESULTS: Beauveria bassiana colonization rates ranged from 73% (Rinconete) to 85% (Galia) and were associated with melon crop-specific VOCs such as cis-3-hexenal and N,N-dimethyldodecanamine. The B. bassiana colonization also triggered cultivar-specific VOCs including allomones and synomones that play a key role in melon–insect pest interactions which are relevant to crop protection. These included cis-3-hexenol and ⊎-phellandrene in Galia, cinnamaldehyde and cinnamyl alcohol in Futuro, and styrene and acetophenone in Rinconete. Differences in VOCs were evaluated in a multitrophic system involving cv. Galia, the aphid Aphis gossypii and the predator Chrysoperla carnea. Olfactometer bioassays revealed a lacewing preference for B. bassiana and aphid-infested plants. Significant differences in emissions of lacewing attractant VOCs were recorded between B. bassiana-colonized plants and controls, independent of aphid infestation. CONCLUSION: These results reinforce the potential of endophytic B. bassiana-related VOCs to be managed within integrated melon protection and production strategies tailored to specific melon varieties.
- Heat hardening in grey mullets: physiological responses of juvenile chelon labrosus and chelon aurata under simulated short-term marine heatwavesPublication . Amaral, Inês; Costa, Rita; Zamora-López, Antonio; Zimmermann, Wim; Guerrero-Gómez, Adrián; Gregorio, Silvia; Guerreiro, Pedro MiguelIntroduction: Marine heatwaves are increasing in frequency and intensity, posing major challenges for fishes inhabiting shallow coastal ecosystems. Short-term exposure to extreme warming can alter metabolic performance and thermal tolerance, with potential consequences for species persistence and school composition in thermally variable habitats. Understanding the capacity of coastal fishes to withstand acute warming events is therefore essential for predicting ecological responses to climate change. Objective: We aimed to determine the effects of simulated marine heatwaves on thermal tolerance and metabolic performance in juvenile grey mullets, Chelon labrosus and Chelon aurata, two abundant sympatric species inhabiting the Ria Formosa lagoon (southern Portugal). Methodology: Juvenile mullets acclimated at 17 °C were exposed to simulated heatwave treatments of 23, 27, or 33 °C and sampled either at peak temperature or after 48 h and 1-week recovery at 17 °C. Critical thermal maximum (CTmax, using a 1 °C/min thermal ramp), static oxygen consumption (MO2), and intermittent respirometry parameters were measured. Standard metabolic rate (SMR), maximum metabolic rate (MMR), and aerobic scope (AS) were derived from intermittent respirometry. A complementary temperature-ramp (>3 h at each temperature step 17, 23, 27 and 33 °C) was performed to evaluate routine metabolic rate and estimate Q10 values across increasing temperatures. Additional plasma and tissue analyses are being conducted to assess energetic substrate mobilization and cellular responses to thermal and oxidative stress. Results: CTmax increased significantly with warming in both treatment modes, demonstrating rapid heat hardening in juvenile mullets. Fish exposed to 27 and 33 °C exhibited higher CTmax than control fish, and this elevated tolerance persisted after recovery. Chelon labrosus showed slightly higher CTmax values than C. aurata. Oxygen consumption increased with temperature, with the strongest responses occurring at 33 °C. SMR increased markedly with warming, particularly in heatwave-exposed fish, while MMR increased mainly at the highest temperature treatment. In contrast, AS showed no clear thermal optimum or decline across treatments. Routine metabolic rate increased non-linearly with temperature in the complementary ramp experiment, with a mean Q10 of 2.28, confirming strong thermal dependence of metabolism. Conclusions: Juvenile mullets possess substantial short-term thermal plasticity and can rapidly increase heat tolerance during marine heatwaves but this enhanced tolerance is accompanied by elevated metabolic costs under extreme warming, indicating potential energetic trade-offs near upper thermal limits. Differential physiological responses between species may influence school composition and ecological performance across thermal landscapes. Ongoing plasma and tissue analyses will further clarify the energetic and cellular mechanisms underlying thermal and oxidative stress resilience in coastal fishes.
- ESG variations across banking loan types: evidence from european listed banksPublication . Francisco, Paulo Morais; Couto, EduardoBuilding on social‐capital theory and transaction‐cost theory, we examine whether European banks' rated ESG performance varies systematically with the composition of their loan portfolios. Merging Refinitiv ESG scores with Orbis Bank Focus loan‐ book data for 51 EU‐listed banks over 2005–2022, we estimate pooled OLS, random‐effects, fixed‐effects, lagged‐variable, and dynamic System‐GMM specifications. The evidence points to one robust regularity and two more qualified patterns. First, banks with higher mortgage‐loan shares tend to have lower ESG ratings: a one‐standard‐deviation increase in mortgage intensity is associated with an approximately three‐point lower composite ESG score and up to five points lower environmental pillar score, and the negative mortgage association remains visible in the dynamic System‐GMM models. Second, consumer‐loan intensity is positively associated with ESG ratings in random‐effects, fixed‐effects, and lagged fixed‐effects specifications, particularly for the environmental and social pillars, but this association is not statistically significant in the dynamic System‐GMM models. Third, corporate‐loan exposure shows no stable relationship with overall ESG ratings. We interpret these patterns as consistent with a trust‐intensity mechanism: ESG commitments and lending technologies appear to align differently across collateral‐rich, standardised lending and softer‐information retail activities.
- Transitional waters: Critical habitats for coastal fish species and fisheriesPublication . Erzini, KarimTransitional waters—such as estuaries, lagoons, deltas, and coastal wetlands—are dynamic environments where freshwater and seawater interact, forming highly productive and biologically diverse ecosystems. Shaped by temperature and salinity gradients, tidal influence, sediment transport, and nutrient-rich conditions, these habitats support diverse ecological functions. Their structural complexity—including seagrass beds, salt marshes, mudflats, and mangroves—provides essential habitats for many fish species. These areas are crucial for fish life cycles, serving as nurseries, spawning grounds, feeding zones, and refuges from predators. Many commercially important species depend on them during early life stages before moving offshore, making them vital for both commercial and recreational fisheries. Beyond food provision, they deliver key ecosystem services, including water purification, coastal protection, and carbon storage. Research on the fish community of the Ria Formosa lagoon in Portugal since the 1980s highlights long-term changes in the fish community and the dominant role of habitat structure and temporal dynamics. Subtidal seagrass beds support higher fish abundance and diversity than unvegetated areas, acting as key nursery habitats and provide important fish provisioning services. Seasonal variation is also central, driven by recruitment pulses of marine migrants in late winter–spring. Recent pressures on this system have been driven by human activity and environmental change. Seagrass loss reduces nursery and feeding areas, while pollution degrades water quality. Overfishing (including illegal fishing), recreational activities, and aquaculture expansion add stress. Climate warming and invasive species such as Caulerpa prolifera, further disrupt ecosystem balance and threaten biodiversity. Sustainable management—such as habitat restoration, protected areas, and integrated policies—is essential to preserve the ecological and economic value of this unique lagoon. Ongoing research, monitoring, habitat restoration, and stakeholder engagement remain critical for ensuring resilience.
- Marine recreational fishing in Portugal: Social and biological perspectives for improved managementPublication . Nuñez Velazquez, Samira; Guerreiro, Pedro Miguel; Gonçalo Jacinto; Veiga, Pedro; Rangel, MafaldaMarine recreational fishing (MRF) is a socially, economically, and ecologically important activity. However, the absence of systematic monitoring and research in Portugal has limited a comprehensive understanding of the sector and its broader implications. Addressing these gaps is essential to support evidence-based and adaptive recreational fisheries management.