Department for Safety in the Food Chain, German Federal Institute for Risk Assessment (BfR), Max‑Dohrn‑Str. 8‑10, 10589, Berlin, Germany.
Leibniz Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany.
Mycotoxin Res. 2023 May;39(2):109-126. doi: 10.1007/s12550-023-00477-3. Epub 2023 Mar 16.
Fungi of the genus Alternaria are ubiquitous in the environment. Their mycotoxins can leach out of contaminated plants or crop debris into the soil entering the plant via the roots. We aim to evaluate the importance of this entry pathway and its contribution to the overall content of Alternaria toxins (ATs) in wheat plants to better understand the soil-plant-phytopathogen system. A hydroponic cultivation system was established and wheat plants were cultivated for up to two weeks under optimal climate conditions. One half of the plants was treated with a nutrient solution spiked with alternariol (AOH), alternariol monomethyl ether (AME), and tenuazonic acid (TeA), whereas the other half of the plants was cultivated without mycotoxins. Plants were harvested after 1 and 2 weeks and analyzed using a QuEChERS-based extraction and an in-house validated LC-MS/MS method for quantification of the ATs in roots, crowns, and leaves separately. ATs were taken up by the roots and transported throughout the plant up to the leaves after 1 as well as 2 weeks of cultivation with the roots showing the highest ATs levels followed by the crowns and the leaves. In addition, numerous AOH and AME conjugates like glucosides, malonyl glucosides, sulfates, and di/trihexosides were detected in different plant compartments and identified by high-resolution mass spectrometry. This is the first study demonstrating the uptake of ATs in vivo using a hydroponic system and whole wheat plants examining both the distribution of ATs within the plant compartments and the modification of ATs by the wheat plants.
交链格孢属真菌在环境中无处不在。它们的真菌毒素可以从受污染的植物或作物残渣中浸出到土壤中，通过根部进入植物。我们旨在评估这种进入途径的重要性及其对小麦植物中交链格孢毒素（ATs）总含量的贡献，以更好地了解土壤-植物-植物病原菌系统。建立了水培培养系统，并在最佳气候条件下对小麦植物进行了长达两周的培养。一半的植物用含有交链孢酚（AOH）、交链孢酚单甲醚（AME）和 tenuazonic 酸（TeA）的营养液处理，而另一半植物则在没有真菌毒素的情况下培养。在 1 周和 2 周后收获植物，并使用基于 QuEChERS 的提取和内部验证的 LC-MS/MS 方法分别分析根、冠和叶中的 ATs。ATs 通过根部吸收并在培养 1 周和 2 周后运输到整个植物中，直到叶片，根部的 ATs 水平最高，其次是冠部和叶片。此外，在不同的植物部位检测到大量的 AOH 和 AME 缀合物，如葡萄糖苷、丙二酰葡萄糖苷、硫酸盐和二/三己糖苷，并通过高分辨率质谱法进行了鉴定。这是第一项使用水培系统和全小麦植物研究体内 ATs 摄取的研究，同时研究了 ATs 在植物部位内的分布以及 ATs 被小麦植物修饰的情况。
