This study investigated the stress responses of cinnamic acid (CA) in pea plants and explored the protective role of spermidine (SPD) against CA-induced adverse effects. Pea seedlings exposed to CA had reduced length, biomass, moisture, chlorophyll, sugar, and protein contents and reduced nitrate reductase activity. These parameters increased when SPD was applied alone and in combination with CA. Electrolyte leakage and malondialdehyde content were high in seedlings treated with CA but decreased when the SPD + CA treatment was applied. Foliar exposure to SPD partially mitigated CA-induced stress effects by strengthening the antioxidant defense system, which helped preserve the integrity of biochemical processes. These results indicate that SPD (1 mM) could mitigate the adverse effects of CA and enhance plant defense system. Hence, SPD can be used as a growth regulator for the maintenance of physiological functions in pea plants in response to the pernicious consequences of CA stress.

这项研究调查了豌豆植物中肉桂酸（CA）的胁迫反应，并探讨了亚精胺（SPD）对CA诱导的不良反应的保护作用。暴露于CA的豌豆幼苗的长度，生物量，水分，叶绿素，糖和蛋白质含量减少，硝酸盐还原酶活性降低。当单独使用SPD并与CA结合使用时，这些参数会增加。用CA处理的幼苗的电解质渗漏和丙二醛含量高，但当采用SPD + CA处理时降低。叶面暴露于SPD可以通过增强抗氧化防御系统来部分缓解CA诱导的应激效应，这有助于保持生化过程的完整性。这些结果表明，SPD（1 mM）可以减轻CA的不利影响并增强植物防御系统。因此，