This study examines the effects of the extreme drought and heatwaves that occurred in Romania during the summer of 2024 on the microbiological and mycotoxicological quality of wheat (Triticum aestivum) stored until April 2025, as well as on the quality of wholemeal flour and bread derived from it. Comparative analyses were conducted against the contamination in wheat harvested in 2024. The hot and dry conditions significantly influenced the microbial and mycotoxicological contamination of both freshly harvested and stored wheat, as well as the derived flour and bread, due to their notably reduced moisture content and water activity. Although levels of total fungi, Fusarium-damaged kernels, and mycotoxins deoxynivalenol, aflatoxin B1, and ochratoxin A remained well below regulatory thresholds, higher contamination was observed in Transylvania and Moldavia—particularly in the Curvature Carpathians, likely due to their cooler and wetter microclimates. The observed quality changes were strongly associated with alterations in physico-chemical, rheological, and colorimetric parameters, posing potential economic challenges for the milling and baking industries. The study recommends implementing integrated regional strategies to enhance wheat resilience, optimize production systems, and improve contamination control in response to increasing climate stress across Southeastern Europe.

This article assesses the occurrence of Fusarium-damaged kernels (FDKs) in common wheat (Triticum aestivum) under the influence of environmental factors and extreme weather events in Romania (exceptionally high air temperatures and extreme pedological drought produced by a dipole block in summer 2015, and extreme precipitation and floods produced by an omega block in spring 2016). Wheat samples (N = 272) were analyzed for FDKs via visual estimation and manual weighing according to ISO 7970 and are statistically evaluated using SPSS. The dipole block in 2015 reduced the effects of environmental factors to non-significant correlations with FDKs, while the omega block in 2016 was non-significantly to very significantly correlated with FDKs in the northwestern and western regions. The occurrence of FDKs was favored for wheat cultivation in acidic soils and inhibited in alkaline soils. Wheat samples with FDKs ≥ 1% were sampled from crops grown in river meadows with high and very high risks of flooding. Knowing the contaminants’ geographical and spatial distributions under the influence of regular and extreme weather events is important for establishing measures to mitigate the effects of climate change and to ensure human and animal health.

This study examines the microbiological and mycotoxicological quality of common wheat in Romania in the extremely dry 2023–2024 agricultural year. Common wheat grown in the West Plain, Southern Hilly Area, Transylvania, and northern Moldavia (45–48° N, 21–27° E) had higher moisture content, water activity, Fusarium-damaged kernels, and deoxynivalenol levels. This was due to moderate temperatures, abundant precipitation, and soil water reserves in May, followed by moderate drought from June to August. Conversely, common wheat from the Oltenia Plain, the Southern Plain, and southern Moldavia (43–46° N, 23–28° E) had the lowest contamination levels, attributed to extreme temperatures and drought during June–August. Common wheat from Dobrogea (45° N, 28° E) showed the highest total fungi contamination, which was influenced by precipitation at harvest. Although microbiological and mycotoxicological contamination was low, it negatively affected the physico-chemical and sensory–colorimetric parameters of common wheat, particularly in the West Plain, Oltenia Plain, and Dobrogea. Consequently, there could be significant economic losses for farmers, storekeepers, millers, and bakers, as well as a decline in the quality of finished foods. Moreover, the coexistence of deoxynivalenol and total aflatoxins in common wheat grown in the northwest of the country indicates the spread of contamination due to dry conditions and climate change.