The plant peptide hormone phytosulfokine promotes somatic embryogenesis by maintaining redox homeostasis in Cunninghamia lanceolata

Somatic embryogenesis (SE) are widely used for studying the mechanisms of embryo development. However, little is known about the underlying mechanisms especially in woody plants. Previous studies have revealed a SE system has been well-established for Cunninghamia lanceolata, but in a genotype-dependent manner which limits its application in practice. Here, we found that phytosulfokine (PSK), a plant peptide hormone, can not only increase SE efficiency, but also establish SE in those recalcitrant genotypes of C. lanceolata. PEM browning and determination of hydrogen peroxide (H