Mitigation effects of exogenous acetic acid on drought stress in Cunninghamia lanceolata

Aim As an environment friendly regulating factor, acetic acid (AA) plays an important role in linking basic physiological progresses and hormone signaling. Methods In this study, seedlings of Cunninghamia lanceolate collected from two different rainfall regions were used to explore the effects of exogenous AA. Results The results indicated that exogenous AA (200 mM) could eliminate drought-induced damages. The application of AA to soils could induce needle abscisic acid accumulation to decrease stomatal conductance and transpiration rate and further lead to the maintenance of needle water content and water use efficiency. Meanwhile, AA promotes the photosynthetic activity and photo-protection by increasing the contents of chlorophyll pigments and the activity of PSII reaction center. The alleviation of electrolyte leakage and malondialdehyde induced by drought, accompanied by the enhancement of the ROS scavenging system and osmotic regulation indicated that AA could protect cell membrane and eliminate oxidative toxicity. Additionally, this work further showed the provenance-specific responses to exogenous AA and demonstrated the feasibility of exogenous AA in larger pot experiments for woody plants. Conclusion Overall, our study provides evidence that exogenous AA can strengthen the ability of C. lanceolate seedlings against drought as a positive regulator. Therefore, the irrigation of appropriate doses of AA into soils can be an effective practice against drought for Chinese fir forests.

Automated summary

In this study, the effects of exogenous acetic acid (AA) on Cunninghamia lanceolate seedlings were investigated. The results showed that AA could alleviate drought-induced damages by regulating physiological processes and protection mechanisms.