Fungal and plant secondary metabolites modulate host-pathogen interactions. However, the participation of fumonisin B1 (FB1) in the Fusarium verticillioides-maize pathosystem is unclear. In this work, cell death and the reactive oxygen species-phytohormone imbalance interplay as well as their correlation with the FB1 phytotoxicity in two maize genotypes with contrasting resistance to Fusarium ear rot were studied. Resistant (RH) and susceptible hybrid (SH) maize seedlings, grown from uninoculated seeds irrigated with FB1 (1 and 20 μg/mL), were harvested at 7, 14 and 21 days after planting, and were examined for electrolyte leakage (aerial parts) and for oxidative stress biomarkers (aerial parts and roots). The salicylic/jasmonic acid levels associated with cytotoxicity were further explored in seedlings exposed 24 h to FB1 (1 μg/mL) in hydroponics, with and without pre-treatment with the antioxidant ascorbic acid (AA). Cell death increased in RH and SH watered with 1 and 20 μg/mL of mycotoxin, respectively. Both toxin concentrations were pro-oxidant, and the major perturbations were found in roots. The overall plant stress, estimated by an Integrated Biomarker Response index, was higher in plants treated with 20 μg/mL of FB1, while treatment with 1 μg/mL caused more stress in RH at 21 days. Different phytohormone changes were found in both hybrids: salicylic acid increases (prevented by AA) in RH, and jasmonic acid decreases in both germplasms (although prevented by AA pre-treatment only in SH). Cell death induced by FB1 was associated with different phytohormonal regulatory mechanisms in both maize genotypes, some of which were mediated by the redox status.

真菌和植物次生代谢物调节宿主-病原体相互作用。然而，伏马菌素 B1 (FB1) 在轮枝镰刀菌- 玉米病理系统中的作用尚不清楚。在这项工作中，细胞死亡和活性氧物质-植物激素失衡相互作用，以及它们与两种对镰刀菌具有不同抗性的玉米基因型中的 FB1 植物毒性的相关性耳腐进行了研究。在种植后 7、14 和 21 天收获抗性 (RH) 和易感性 (SH) 玉米幼苗，由未接种的种子用 FB1（1 和 20 μg/mL）灌溉，并检查电解质泄漏（地上部分) 和氧化应激生物标志物（地上部分和根）。在水培中暴露于 FB1 (1 μg/mL) 的幼苗 24 小时后，进一步探索了与细胞毒性相关的水杨酸/茉莉酸水平，有和没有用抗氧化剂抗坏血酸 (AA) 预处理。在分别用 1 和 20 μg/mL 霉菌毒素浇水的 RH 和 SH 中，细胞死亡增加。两种毒素浓度都是促氧化剂，并且在根中发现了主要的扰动。通过综合生物标志物反应指数估计的整体植物胁迫在用 20 μg/mL FB1 处理的植物中更高，而 1 μg/mL 的处理在 21 天时会在 RH 中引起更大的压力。在两种杂交种中发现了不同的植物激素变化：RH 中水杨酸增加（AA 阻止），两种种质中茉莉酸减少（尽管仅在 SH 中通过 AA 预处理阻止）。FB1 诱导的细胞死亡与两种玉米基因型中不同的植物激素调节机制有关，其中一些是由氧化还原状态介导的。