Morpho-Physiological and Stress-Related Gene Expression of Rice Varieties in Response to Salinity Stress at Early Vegetative Stage

This study focuses on the growth and morpho-physiological responses of Malaysian commercial variety MR219 rice to salinity stress during early vegetative stages, specifically germination five-leaf stage. For responses, seeds were grown for 10 days in different salt concentrations. Low significantly improves seed increases total number germinated seeds. However, higher (160 mM NaCl) inhibits reduces by 93.3%. The effects stage also determined compared salinity-tolerant (Pokkali) susceptible (IR64) varieties. There significant reductions photosynthesis rate, transpiration stomatal conductance, leaf chlorophyll content 28.1%, 58.6%, 81.1%, 3.7%, respectively. These could contribute decrease parameters measured throughout treatment period. Based principal component analysis (PCA) result, is more tolerant than IR64, but less Pokkali. Further investigation stress-related gene expression suggests that changes transcript level genes involved gamma-aminobutyric acid (GABA) shunt, ion transport, reactive oxygen species detoxification be attributed adaptation tolerance each stress.