Figure 1.

Schematic representation of rice (Oryza sativa L.) seed structure, depicting how salinity stress inactivates endogenous GA3, leading to the inhibition of both rice seed germination and seedling growth. Figure adapted from (Koning, 1994; Ma et al., 2017). Exogenous GA3 application reactivates endogenous GA3, enhancing rice seed germination and seedling growth. GA3 activation also upregulates the α-amylase genes (OsAmy1A, OsAmy1C, and OsAmy3C) that may help to degrade starch contents and convert them into sugar. Later, this sugar serves as food for young plants (embryos) in which seed germination and seedling growth is restored. In the diagram, the red color letter indicates the suppression of seed germination and inactivation of GA3, whereas the green color represents the stimulation of seed germination and activation of GA3. The pink color indicates the activation of the α-amylase genes, which prevented seed germination due to the saline effect.