Fusarium graminearum is considered the main cause of Fusarium head blight (FHB) in Argentina. The development of this pathogen is dependent on weather conditions, and its occurrence results in economic losses associated with yield reduction, lower quality of grains, and frequent contamination with mycotoxins. The main inoculum source for FHB is F. graminearum perithecia in crop debris where the pathogen survives saprophytically. The adoption of conservationist tillage practices, which leave crop residues on the soil surface, impacts on the volume of inocula available which, in combination with the lack of FHB resistant wheat cultivars, increases the risk of disease development. Our objective was to analyze the long-term dynamics of F. graminearum inocula on different winter and summer crop residues. To do so, five winter cereal species (soft and durum wheat, barley, rye and tritordeum) were cultivated and harvested, and soybean was sown under no-till on the crop debris. The presence and viability of Fusarium graminearum propagules were later evaluated on the residues of the six crops in the 14 months following the harvest of soybean. A qPCR fungal quantification method was developed using previously available primers. The results obtained confirmed the presence and viability of the inoculum in all substrates throughout the time considered. Furthermore, a direct relationship was found between the amount of inoculum in the residues of the soybean sown under a zero-tillage system and the inoculum in the residues of the winter cereals previously sown. This research provides information that could help reduce the sources of F. graminearum inoculum and establish pre-harvest management strategies aimed at preventing mycotoxin contamination in the food chain.

禾谷镰刀菌被认为是阿根廷赤霉病（FHB）的主要原因。该病原体的生长取决于天气条件，其发生会导致与减产、谷物品质下降和频繁受到霉菌毒素污染相关的经济损失。 FHB 的主要接种源是作物残骸中的禾谷镰刀菌子囊壳，病原体在其中腐生生存。采用保护性耕作方法会将农作物残留物留在土壤表面，影响了可用接种量，再加上缺乏抗 FHB 小麦品种，增加了疾病发生的风险。我们的目的是分析禾谷镰刀菌接种物对不同冬季和夏季作物残留物的长期动态。为此，种植和收获了五种冬季谷物（软质小麦和硬质小麦、大麦、黑麦和黑麦），并在作物残骸上免耕播种了大豆。随后在大豆收获后 14 个月内对六种作物残留物中的禾谷镰刀菌繁殖体的存在和活力进行了评估。使用先前可用的引物开发了 qPCR 真菌定量方法。获得的结果证实了在整个考虑的时间内所有基质中接种物的存在和活力。此外，还发现零耕系统下播种的大豆残留物中的接种量与先前播种的冬季谷物残留物中的接种量之间存在直接关系。这项研究提供的信息有助于减少禾谷镰刀菌接种物的来源，并制定旨在防止食物链中霉菌毒素污染的收获前管理策略。