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Seed germination is critical to agricultural productivity because low germination rates and/or asynchronous germination negatively affect stand establishment and subsequent yields. Exposure to high temperatures during seed imbibition can decrease both germination synchrony and rates through an ABA-mediated process called thermoinhibition. Methods to reduce thermoinhibition would be agriculturally valuable, particularly with increasing global mean temperatures. Lettuce seed germination is particularly sensitive to high temperatures and is a classic system for studying thermoinhibition. Extensive evidence using mutants and carotenoid biosynthetic inhibitors (e.g. fluridone) has demonstrated that endogenous abscisic acid (ABA) biosynthesis is required for thermoinhibition in lettuce and Arabidopsis. Although fluridone and related carotenoid biosynthetic inhibitors block thermoinhibition, they are not well-suited for this application due to their herbicidal effects. Here we explore the potential of ABA receptor antagonism to disrupt thermoinhibition using antabactin (ANT), a broad-spectrum high-affinity receptor antagonist. We show low μM ANT treatments (10 μM) during lettuce seed imbibition reduces thermoinhibition at temperatures of up to 40°C, demonstrating that ABA signaling is required for thermoinhibition and that receptor antagonists are well-suited anti-thermoinhibition agents. We further explored interactions between ANT and seed priming, which is used commercially to improve seed germination and reduce thermoinhibition and is achieved by partial hydration and subsequent desiccation of seeds. We show that co-priming with ANT improves germination at elevated temperatures better than priming alone, and thus, the two treatments can be combined to improve germination. Our data demonstrate that ABA antagonists are potentially useful agrochemical leads for mitigating the effects of high temperatures on seed germination and stand establishment that may be of increasing importance due to climate change. More generally, ABA antagonists should be useful in physiological processes where ABA’s effects are counterproductive to yield.种子萌发对农业生产至关重要，因为萌发率低下和/或萌发不同步会对苗床建植及后续产量产生负面影响。种子吸胀（seed imbibition）期间遭遇高温，可通过脱落酸(abscisic acid, ABA)介导的热抑制（thermoinhibition）过程，同时降低种子萌发的同步性与萌发率。降低热抑制的方法具备农业应用价值，在全球平均气温持续升高的背景下尤为如此。生菜种子萌发对高温尤为敏感，是研究热抑制的经典模式系统。借助突变体与类胡萝卜素生物合成抑制剂（如氟啶酮(fluridone)）开展的大量研究证据表明，内源脱落酸(ABA)的生物合成是生菜与拟南芥(Arabidopsis)发生热抑制的必要条件。尽管氟啶酮及相关类胡萝卜素生物合成抑制剂可阻断热抑制，但由于其具有除草活性，并不适合该应用场景。本研究借助广谱高亲和性受体拮抗剂安塔巴汀(antabactin, ANT)，探究ABA受体拮抗作用干扰热抑制的潜力。我们发现，在生菜种子吸胀阶段施加低浓度μM级别的ANT处理（10 μM），可在最高40℃的温度下缓解热抑制，这证明ABA信号通路是热抑制过程的必需条件，同时也表明受体拮抗剂是适配性良好的抗热抑制试剂。我们进一步探究了ANT与种子引发（seed priming）的相互作用：种子引发是一项商业化种子处理技术，通过对种子进行部分水合后再干燥，可提升种子萌发能力并缓解热抑制。实验结果表明，与单独使用种子引发相比，将ANT与种子引发联合使用可更有效地提升高温环境下的种子萌发率，因此两种处理手段可结合使用以优化萌发效果。本研究数据表明，ABA拮抗剂有望成为极具应用潜力的农用化合物先导物，用于缓解高温对种子萌发与苗床建植的负面影响——在气候变化加剧的背景下，该需求的重要性将日益凸显。从更广泛的层面而言，在脱落酸的作用对作物产量产生反效益的生理过程中，ABA拮抗剂均可发挥应用价值。