Transcriptomic and physiological analyses reveal that jasmonic acid and abscisic acid coordinately regulate cold stress response in Myriophyllum aquaticum

Myriophyllum aquaticum, renowned for its ability to purify aquaculture wastewater, faces a significant challenge due to its susceptibility to cold stress. However, the molecular mechanisms underlying M. aquaticum's response to cold stress remain poorly understood. In this study, we unraveled the molecular mechanisms governing M. aquaticum's response to cold stress through transcriptome sequencing and physiological analyses. Our investigation revealed 12,684 differentially expressed genes during cold stress. Gene ontology and KEGG analyses demonstrated the involvement of plant hormone signaling and transcriptional reprogramming related genes in M. aquaticum's response to cold stress. Further investigations highlighted the role of jasmonic acid (JA) and abscisic acid (ABA) in M. aquaticum's cold acclimation. Firstly, cold stress significantly increased endogenous levels of JA and ABA in M. aquaticum plants. Secondly, the transcript levels of several crucial JA and ABA signaling genes were prominently elevated, as shown by expression profiling and qRT-PCR analyses. Thirdly, the application of exogenous JA or ABA effectively mitigated foliar damage and improved cold tolerance in M. aquaticum plants. Furthermore, the expression of JA and ABA biosynthesis and signaling genes was significantly upregulated in JA- or ABA-pretreated plants when exposed to cold stress. Collectively, our findings provide evidence that JA and ABA contribute to the cold acclimation of M. aquaticum plants. Our research provides insights into the molecular mechanisms underlying cold acclimation of M. Aquaticum plants and presents a novel strategy to improve their cold tolerance, thereby expanding their potential application in phytoremediation efforts in high latitude areas.