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Salt-stress always leads to growth inhibition of plants. For plant stress response process is mostly associated with endogenous hormone-related signal transduction, Study on the mechanism how hormones adapt plant to the environment is very important to improve the salt tolerance of plants. Hitherto, the effect of exogenous salicylic acid （SA）, Abscisic Acid （ABA）, methyl jasmonate （Me-JA） on salt-stressed rice （Oryza sativa L. Nipponbare） seed germination is uncertain. Though studies have shown that exogenous gibberellic acid （GA3） can alleviate salt stress on rice growth inhibition, the internal mechanism of this process yet need to be well studied.In this paper, we studied the inhibition effect of salt stress on seed germination, and the effect of exogenous SA, ABA, Me-JA and GA3 on the inhibition of salt stress. We also traced the effect of salt-stress and GA3 on rice seedlings from the perspective of proteomics, and then found out proteins which relate to the mechanism GA3 promote salt tolerance of rice. Rice shoots of 5-day-old seedlings grown on H2O, 5 g/L NaCl, 5 g/L NaCl + 100μmol/L GA3, and 100μmol/L GA3 for 48 h were used for protein extraction. The differential expressed proteins revealed by two-dimensional polyacrylamide gel electrophoresis （2-DE） were digested and then analyzed and identified by Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry （MALDI-TOF MS）. This paper also preliminary studied on the application of protein phosphorylation research technology based on the Pro-Q Diamond fluorescent staining as well as fluorescence two dimensional difference gel electrophoresis （2-D DIGE） technology on the proteomics analysis affected by salt and GA3 in rice.The main results of this experiment are as follows:1. Salt stress can significantly inhibit seed germination Nipponbare; Exogenous Salicylic Acid, Abscisic Acid and Methyl Jasmonate can not relieve the inhibition of 5 g/L NaCl stress. While high concentrations of these hormones lead to more significant of the inhibition effect induced by salt; Exogenous GA3 can significantly relieve the inhibitory effect of 5 g/L NaCl.2. After separated and analyzed by 2-DE, twelve salt regulated and 1 GA3 regulated protein were obtained. Eleven of these proteins were identified as Glutamyl-tRNA reductase （GluTR）, Enolase, Salt stress-induced protein （Salt protein）, Os09g0249700, Hypothetical protein OsJ014066, Putative chaperonin 21 precursor, Os04g0659300, Hypothetical protein OsJ025258, RuBisCO activase small isoform precursor, Isoflavone reductase-like protein and phosphoglucomutase. Isoflavone reductase-like protein and phosphoglucomutase may play important role in the mechanism, through which exogenous GA3 relieved the salt induced inhibition of rice seedlings.3. By using Pro-Q Diamond fluorescent dye, an average of 602, 566, 649 and 697 phosphorylated proteins were detected from 2-DE gels from the four treatment groups （H2O, 5 g/L NaCl, 5 g/L NaCl + 100μmol/L GA3 and 100μmol/L GA3）; In 2-D DIGE images, an average of 2 703 protein spots were detected.
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