Chilling stress is one of the limiting factors for late sowing of winter rapeseed (Brassica napus L.) and early sowing of spring
rapeseed. Seed priming can efectively alleviate chilling stress during germination, but the potential mechanism with regard
to how rapeseed responds to chilling stress is unclear based on metabolomics. Therefore, in this study, seeds were soaked in
hydrogen peroxide or water for 8 h. They were then germinated together with untreated seeds under low temperature (8 °C).
After priming treatment, liquid chromatography coupled with mass spectrometry was used to investigate the key metabolites and metabolic pathways involved in the germination of rapeseed under low temperature. A ... More
Chilling stress is one of the limiting factors for late sowing of winter rapeseed (Brassica napus L.) and early sowing of spring
rapeseed. Seed priming can efectively alleviate chilling stress during germination, but the potential mechanism with regard
to how rapeseed responds to chilling stress is unclear based on metabolomics. Therefore, in this study, seeds were soaked in
hydrogen peroxide or water for 8 h. They were then germinated together with untreated seeds under low temperature (8 °C).
After priming treatment, liquid chromatography coupled with mass spectrometry was used to investigate the key metabolites and metabolic pathways involved in the germination of rapeseed under low temperature. A total of 6176 metabolites
were detected. We summarized 19 diferent metabolites in response to priming treatment, identifed four key diferential
metabolites (l-γ-glutamylcysteine, l-argininosuccinate, l-glutamate, and glutathione), and established a metabolic pathway
centered on glutathione metabolism and amino acid metabolism (including arginine biosynthesis and alanine, aspartate
and glutamate metabolism). The results showed that hydrogen peroxide-primed seeds preferentially increased glutathione
metabolism after priming, enhanced antioxidant capacity and alleviated chilling stress during germination. An increase in
the metabolites involved in cell energy supply and amino acid metabolism was found during germination, resulting in a
shorter average germination time and better germination percentage. This experiment revealed the metabolic pathway of the
germination of hydrogen peroxide-primed seeds under chilling stress, which provides a theoretical basis for future studies
on the chilling resistance of rapeseed.
