Background: Banana Fusarium wilt inflicts enormous economic losses on global banana production; however, effective control strategies remain elusive. We previously demonstrated that overexpression of plantain (Musa paradisiaca) ICE1 (MpICE1) significantly enhances banana resistance to Fusarium wilt. This study aimed to screen and identify key resistance genes associated with banana Fusarium wilt resistance and further explore their molecular functions and regulatory mechanisms, so as to provide a solid theoretical basis for the genetic breeding and disease resistance improvement of banana. Methods: Based on our previous transcriptomic dataset and the current metabolomic analysis, we identified a key gene encoding 12-oxo-phytodienoic acid reductase, MaOPR1, involved in the linoleic acid metabolism pathway, and functionally validated its role via dsRNA-mediated gene silencing. Results: Silencing of MaOPR1 alleviated banana leaf-lesion response after Fusarium wilt. Conclusions: Integrating metabolomic and dsRNA-silencing evidence, MaOPR1 acts as a negative regulator of banana Fusarium wilt resistance, associated with alpha-linolenic acid metabolic reprogramming in the MpICE1-overexpressing background.

Isodon serra is a medicinal plant distributed in the Lingnan region of China. However, I. serra seeds are sensitive to heat, limiting germination in Lingnan’s climate. Seed priming technology provides an effective means to address this problem. Meanwhile, karrikin (KAR) enhances plant growth and stress tolerance, but its mechanism in I. serra remains unclear. Therefore, in this study, different KAR concentrations were selected for priming to examine the phenotypic and physiological responses, and multi-omics analysis was used to explore the molecular mechanism of promoted germination under heat stress. The optimal concentration of 0.05 µmol/L KAR raised the seed germination rate under heat stress. This priming treatment reduced membrane damage, indicated by lower malondialdehyde (MDA) levels and relative electrical conductivity (REC) and oxidative stress, by regulating antioxidant enzymes and increasing glutathione (GSH) content. Multispectral phenotyping revealed distinct spectral features at 880 nm and 970 nm in primed seeds, correlating with enhanced vigor. Integrated multi-omics analysis demonstrated that the alleviation of heat stress was primarily mediated through the glutathione metabolism pathway, with key roles played by genes such as cluster-23509.3, cluster-15076.0, and cluster-22471.0. In summary, KAR priming enhances osmotic adjustment, improves reactive oxygen species (ROS)-scavenging enzyme activities, and regulates glutathione metabolism to mitigate heat stress in I. serra. These findings provide valuable insights for optimizing the cultivation and management of I. serra under heat stress conditions.