Hormesis is a dose–response phenomenon that is characterized by stimulation at low doses and inhibition at high doses. Extensive evidence has accumulated showing the occurrence of hormesis in numerous plant species independent of physicochemical agents, and this phenomenon has become a target for achieving greater crop productivity. Biostimulants (i.e., elicitors) are agents that activate adaptive responses, moderately stimulate biological performance and aid plants in tolerating stress when applied at low doses that fall within the stimulatory zone of a dose–response curve. Biostimulants based on seaweed liquid extracts (SLEs) are widely known to exert great benefits in plants at very low doses. However, the consequences to plants when SLEs are applied at high doses remain underexplored. A dose–response study was performed on mung bean (Vigna radiata) seedlings by applying a wide range of SLE doses to evaluate growth stimulation patterns. While the application of SLEs at high concentrations mostly caused a decrease in various morphological parameters, the application of SLEs at low concentrations stimulated some of these. Nevertheless, common features of SLE stimulation were present. Mung bean shoot length, root length, and dry weight responded to the SLE concentrations in a hormetic manner. A biphasic dose–response confirmed the relationships between SLE dose and mung bean plant growth parameters, which were due to the properties of the constituents of the SLE of each seaweed species. The SLE growth stimulation pattern found in this study will contribute to the establishment of safe application doses. This paper provides a strong foundation for enhancing the research protocols of studies on the effects of SLEs on plant growth and supports incorporating hormesis into risk assessment practices in agriculture.

兴奋剂是一种剂量反应现象，其特征在于低剂量刺激和高剂量抑制。积累的大量证据表明，许多植物物种中都存在激素效应，而与理化因子无关，这种现象已成为实现更高农作物生产率的目标。生物刺激剂（激发子）是在剂量-反应曲线的刺激区域内以低剂量施用时，能够激活适应性反应，适度刺激生物性能并帮助植物耐受胁迫的药剂。众所周知，基于海藻液体提取物（SLEs）的生物刺激剂可在极低剂量的植物中发挥巨大作用。但是，仍未充分探讨高剂量SLE对植物的危害。对绿豆进行了剂量-反应研究（豆），通过应用各种剂量的SLE来评估生长刺激模式。虽然高浓度SLE的应用主要导致各种形态学参数的降低，但低浓度SLE的应用刺激了其中一些。然而，存在SLE刺激的共同特征。绿豆芽长，根长和干重对SLE的浓度起反响。双相剂量反应证实了SLE剂量与绿豆植物生长参数之间的关系，这是由于每种海藻物种的SLE成分的特性所致。在这项研究中发现的SLE生长刺激模式将有助于确定安全的应用剂量。