Submergence stress does severe harm to rice production. Evaluation of rice submergence tolerance at tillering stage was set up in the paper, submergence tolerance of 19 varieties at tillering stage was evaluated. At one time, physiologic and biochemical changes between hybrid and inbred rice after different submergence stress was compared in the paper. Then , Differential Display Reverse Transcript Polymerase Chain Reaction (DDRT—PCR)was applied to study the differences of gene expression profile between th...