Papaya seed germination and growth improvement linked to cold plasma–induced transcriptomic shifts

Cold plasma has been widely reported to enhance seed germination and plant growth, as demonstrated in both previous research and our earlier studies. However, the molecular mechanisms underlying these physiological improvements remain poorly understood. To address this gap, we investigated the transcriptomic responses of papaya seeds (Carica papaya) following a 10-second argon plasma treatment. Optical emission spectroscopy (OES) identified argon and oxygen species as the predominant reactive components during plasma discharge, suggesting their involvement in regulating cellular functions. RNA sequencing indicated significant upregulation of genes involved in sucrose metabolism, redox homeostasis, and hormone regulation. Notably, PHYB expression increased 8.5-fold, suggesting plasma-mediated modulation of ABA signaling, while RGL homolog expression decreased 7.8-fold, releasing inhibition on TCP14 to promote seedling growth. Significant increases were also observed in key metabolic enzymes, including alkaline/neutral invertase and purple acid phosphatase. This comprehensive analysis provides insights into the molecular pathways influenced by cold plasma, underscoring its potential for agricultural applications. Key metabolic enzymes, including alkaline/neutral invertase and purple acid phosphatase, were also significantly elevated. These results provide molecular evidence that cold plasma treatment enhances seed readiness for germination through coordinated regulation of metabolism, hormonal pathways, and cell growth, highlighting its potential for agricultural applications.