Effects of organic selenium on metabolic responses and disease resistance in rose plants

Selenium (Se) has been widely studied for its ability to effectively induce disease resistance in crops. However, the effects of organic Se on plant immunity and flowering remain poorly understood. In this study, we employed physiological, transcriptomic, and metabolomic approaches to investigate the impact of organic Se on rose plants. Our findings revealed that organic Se inhibited bud production and corolla unfolding. Individual metabolites, including jasmonic acid (JA) and glutathione (GSH), were found to significantly influence flowering. As Se concentrations increased, the levels of ABA and JA in flowers also elevated. Furthermore, Se upregulated genes involved in the pentose phosphate cycle (e.g., galm and idnk), and metabolites such as D-gluconate and glucose, which are early signals for flower induction. Phytohormones were observed to regulate sugar metabolism, linking Se-induced changes to flowering processes. Se application also altered linoleic acid and α-linolenic acid metabolism, affecting JA synthesis. Key genes encoding LOX2S (Rru01G000760, Rru05G070200, Rru05G070220) and AOS (Rru06G051490) were significantly upregulated. Interestingly, metabolites that increase disease resistance were found to inhibit flowering, suggesting that abnormal flowering may be a plant response to stress resistance. Moreover, low concentrations of Se promoted photosynthesis, with the upregulation of genes encoding NADH dehydrogenase, petA, Ppa, petC, petH, and ATPF1G. Se also modulates antioxidant enzymes, phytohormones, and key metabolites, which are critical signaling molecules in the regulation of disease resistance. These findings provide a scientific basis for the application of organic Se in green agriculture and crop health improvement.