Abscisic acid application enhances cadmium accumulation in Sedum plumbizincicola by controlling photosynthesis, hormone signaling and antioxidant defense

Meng Na; Daokun Liu; Shangqi Xu; Xiaoping Li; Xianqing Zheng; Jihai Zhou

doi:10.1016/j.plantsci.2025.112633

Abscisic acid application enhances cadmium accumulation in Sedum plumbizincicola by controlling photosynthesis, hormone signaling and antioxidant defense

Plant Sci. 2025 Jun 25:359:112633. doi: 10.1016/j.plantsci.2025.112633. Online ahead of print.

Authors

Meng Na¹, Daokun Liu², Shangqi Xu¹, Xiaoping Li³, Xianqing Zheng⁴, Jihai Zhou⁵

Affiliations

¹ Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China.
² Forestry Technology Center of Wuhu City, Wuhu 241001, China.
³ Collaborative Innovation Center of Southern Modern Forestry, Nanjing Forestry University, Nanjing 210037, China.
⁴ Institute of Eco-Environment and Plant Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China. Electronic address: zhengxq@163.com.
⁵ Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China; Collaborative Innovation Center of Southern Modern Forestry, Nanjing Forestry University, Nanjing 210037, China. Electronic address: zhoujihai2006@163.com.

PMID: 40578566
DOI: 10.1016/j.plantsci.2025.112633

Abstract

Sedum plumbizincicola (S. plumbizincicola) is a hyperaccumulator species with high potential for the remediation of cadmium (Cd)-contaminated lands. The importance of abscisic acid (ABA) in regulating phytoremediation processes has been widely recognized, but the physiological and molecular mechanisms underlying ABA-mediated Cd uptake and detoxification in hyperaccumulators remain unclear. Here, we investigated how ABA application at low and high rates influenced Cd accumulation and tolerance in S. plumbizincicola, and explored the causal mechanisms. We found that at the late stage of Cd stress, ABA application (≤20 mg·kg^-1 soil) resulted in a more pronounced increase in Cd uptake by ca. 250 % in roots and ca. 50 % in leaves. Exogenous ABA also promoted Cd translocation factor from stems to leaves, which was associated with up-regulated genes related to photosynthesis, ABCB1 transporter, and copper transporter. Under Cd stress, ABA application increased superoxide dismutase activity, as well as contents of glutathione, ascorbic acid, and soluble sugar throughout the growth period. Transcriptome analysis revealed that ABA application under Cd stress significantly upregulated differentially expressed genes (DEGs) involved in hormone signaling related to auxin, cytokinin, and ABA, as well as DEGs involved in small molecule metabolic process. These results indicate that exogenous ABA may alleviate Cd toxicity in S. plumbizincicola by regulating endogenous hormone signal transduction and activating antioxidant defense systems. Overall, our findings provide valuable insights into the role of ABA in enhancing Cd phytoremediation efficiency by hyperaccumulators, advancing strategies for mitigating soil heavy metal contamination.

Keywords: Abscisic acid; Antioxidant; Cadmium contamination; Hyperaccumulator; Transcriptome.