In tryptophan metabolism, the important regulatory genes that were induced after pathogen infection in indica rice were CYP505, HAAO, and MAO, and the genes that were upregulated after infecting japonica rice were CYP505 and DDC. In the lysine synthesis pathway, the regulatory genes LYS2, LYS4, and LYS20 were upregulated after infection in japonica rice but were inhibited or reduced after infection in indica rice. The gene discussed is DDC; the disease is infection.