Climate change (CC) is a complex phenomenon that has the potential to significantly alter marine, terrestrial, and freshwater ecosystems worldwide. Global warming of 2°C is expected to be exceeded during the 21st century, and the frequency of extreme weather events, including floods, storms, droughts, extreme temperatures, and wildfires, has intensified globally over recent decades, differently affecting areas of the world. How CC may impact multiple food safety hazards is increasingly evident, with mycotoxin contamination in particular gaining in prominence. Research focusing on CC effects on mycotoxin contamination in edible crops has developed considerably throughout the years. Therefore, we conducted a comprehensive literature search to collect available studies in the scientific literature published between 2000 and 2023. The selected papers highlighted how warmer temperatures are enabling the migration, introduction, and mounting abundance of thermophilic and thermotolerant fungal species, including those producing mycotoxins. Certain mycotoxigenic fungal species, such as Aspergillus flavus and Fusarium graminearum , are expected to readily acclimatize to new conditions and could become more aggressive pathogens. Furthermore, abiotic stress factors resulting from CC are expected to weaken the resistance of host crops, rendering them more vulnerable to fungal disease outbreaks. Changed interactions of mycotoxigenic fungi are likewise expected, with the effect of influencing the prevalence and co‐occurrence of mycotoxins in the future. Looking ahead, future research should focus on improving predictive modeling, expanding research into different pathosystems, and facilitating the application of effective strategies to mitigate the impact of CC.

Hazelnut (Corylus avellana L.) is a major crop in the Caucasus region, but its safety is often threatened by Aspergillus flavus colonization and aflatoxin contamination. Although aflatoxins (AFs) are strictly regulated in the EU, the influence of post-harvest practices on fungal persistence and AF accumulation remains poorly defined. A three-year study was conducted to evaluate the effects of drying protocols, storage temperature, and conservation practices on fungal growth and AF occurrence in hazelnuts from three producing regions of Azerbaijan. Freshly harvested nuts were subjected to two drying regimes: good drying (sun-exposed, mixed, protected from rewetting) and bad drying (shaded, piled, rewetted). After drying, samples were stored at cold (8–10 °C) or room temperature (18–22 °C). Fungal prevalence was determined by CFU counts with morphological and qPCR identification of Aspergillus section Flavi. AFs were quantified by HPLC, and water activity (a_w) was monitored during storage. Drying emerged as the decisive factor: bad drying consistently resulted in markedly higher fungal loads for A. section Flavi, with mean counts up to 1.3 log10 (CFU/g), compared with 0.8 log10 (CFU/g) under good drying, representing a 7-fold increase. In contrast, storage temperature and shell condition had negligible effects when nuts were properly dried. Aflatoxins were consistently below the 5 µg/kg EU limit for AFB₁ in traced and well-dried samples, whereas market samples occasionally exhibited AFB₁ concentrations >450 µg/kg. These findings highlight drying efficiency as the key determinant of fungal persistence and AF risk in hazelnut post-harvest management.

Aflatoxin contamination in hazelnuts, primarily caused by Aspergillus flavus, poses significant risks to food safety and public health, requiring highly sensitive and robust toxin detection strategies. While conventional culturing techniques remain relevant, they are time-consuming and prone to misidentifications. A molecular workflow for early detection of aflatoxigenic A. flavus in hazelnuts was developed and validated, combining an optimized DNA extraction protocol with quantitative PCR (qPCR) and droplet digital PCR (ddPCR) assays. Four DNA extraction methods were compared for their DNA yields and purity. DNA extraction protocol was optimized introducing a Tween-80 separation step, and was tested on hazelnuts artificially inoculated with aflatoxigenic A. flavus conidia. The optimized protocol was then validated for naturally contaminated hazelnut samples to assess its practical applicability, and to benchmark the performance of qPCR and ddPCR on real samples. The optimized protocol gave yield, purity and amplifiability, and appeared more appropriate for detecting aflatoxigenic A. flavus DNA in complex food matrices such as hazelnuts. The qPCR and ddPCR protocols detected target DNA, with ddPCR offering enhanced sensitivity and superior analytical performance. The developed protocol showed an increased sensitivity and quantification precision compared with previously developed methods. This research provides a validated molecular workflow for the early and sensitive detection of A. flavus in hazelnuts, offering a tool for preventive food safety monitoring and supporting aflatoxin risk assessment strategies for the hazelnut value chain.

Aflatoxin contamination is a growing concern in hazelnut production across the Caucasus, particularly due to its health risks and the economic impact in markets with strict safety standards, such as the European Union. This study examined the genetic diversity and population structure of Aspergillus flavus, the main source of aflatoxin, in three key hazelnut regions of Azerbaijan: Zaqatala, Qabala, and Khachmaz. It also assessed the presence of genotypes genetically similar to known non-aflatoxigenic biocontrol strains using simple sequence repeat (SSR) markers. A total of 710 A. flavus isolates were analyzed using 17 SSR markers, revealing 377 distinct haplotypes and high genetic diversity across regions, seasons, and production stages. Linkage disequilibrium analysis indicated a primarily clonal reproduction pattern, suggesting that dominant genotypes may persist over time and that introduced non-aflatoxigenic strains could remain stable in the population. Among 477 clone-corrected isolates, several haplotypes closely matched the non-aflatoxigenic biocontrol strains MUCL54911 and AF36, which are the active ingredients of the commercial products AF-X1 and AF36 Prevail, suggesting that genotypes potentially suitable for aflatoxin biocontrol may already be present and adapted to the Azerbaijani hazelnut agroecosystem. These findings establish a genetic baseline for A. flavus in Azerbaijani hazelnut systems and support the potential use of MUCL54911 or AF36 for local biocontrol efforts aimed at reducing aflatoxin contamination.