Cao Yang, Du Peihua, Zhang Jiran, Ji Jiahao, Xu Jizhong, Liang Bowen
College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China.
Hortic Res. 2023 May 22;10(7):uhad112. doi: 10.1093/hr/uhad112. eCollection 2023 Jul.
Dopamine has demonstrated promise as a stress-relief substance. However, the function of dopamine in Cd tolerance and its mechanism remains largely unknown. The current study was performed to investigate the mechanism of dopamine on alleviating apple Cd stress through regular application of CdCl and dopamine solution to potting soil. The results indicated that dopamine significantly reduced reactive oxygen species (ROS) and Cd accumulation and alleviated the inhibitory effect of Cd stress on the growth of apple plants through activation of the antioxidant system, enhancement of photosynthetic capacity, and regulation of gene expression related to Cd absorption and detoxification. The richness of the rhizosphere microbial community increased, and community composition and assembly were affected by dopamine treatment. Network analysis of microbial communities showed that the numbers of nodes and total links increased significantly after dopamine treatment, while the keystone species shifted. Linear discriminant analysis effect size indicated that some biomarkers were significantly enriched after dopamine treatment, suggesting that dopamine induced plants to recruit potentially beneficial microorganisms (, , , , , , and ) to resist Cd stress. The co-occurrence network showed several metabolites that were positively correlated with relative growth rate and negatively correlated with Cd accumulation, suggesting that potentially beneficial microorganisms may be attracted by several metabolites (L-threonic acid, profenamine, juniperic acid and (3β,5ξ,9ξ)-3,6,19-trihydroxyurs-12-en-28-oic acid). Our results demonstrate that dopamine alleviates Cd stress in apple trees by recruiting beneficial microorganisms to enhance the physiological resilience revealed. This study provides an effective means to reduce the harm to agricultural production caused by heavy metals.
多巴胺已被证明有望成为一种缓解压力的物质。然而，多巴胺在镉耐受性方面的功能及其机制仍 largely unknown。本研究旨在通过向盆栽土壤中定期施用CdCl和多巴胺溶液，研究多巴胺缓解苹果镉胁迫的机制。结果表明，多巴胺通过激活抗氧化系统、增强光合能力以及调节与镉吸收和解毒相关的基因表达，显著降低了活性氧（ROS）和镉的积累，并减轻了镉胁迫对苹果植株生长的抑制作用。根际微生物群落的丰富度增加，群落组成和组装受到多巴胺处理的影响。微生物群落的网络分析表明，多巴胺处理后节点数量和总连接数显著增加，而关键物种发生了变化。线性判别分析效应大小表明，多巴胺处理后一些生物标志物显著富集，这表明多巴胺诱导植物招募潜在有益微生物（、、、、、和）来抵抗镉胁迫。共现网络显示，有几种代谢物与相对生长速率呈正相关，与镉积累呈负相关，这表明潜在有益微生物可能被几种代谢物（L-苏糖酸、普罗非明、杜松酸和(3β,5ξ,9ξ)-3,6,19-三羟基乌苏-12-烯-28-酸）所吸引。我们的结果表明，多巴胺通过招募有益微生物来增强生理恢复力，从而缓解苹果树的镉胁迫。本研究为减少重金属对农业生产造成的危害提供了一种有效手段。
