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This study was conducted to analyze the variation of yield and grain quality-related traits after inoculation of two Korean bacterial blight races, K1 and K3a in early maturing japonica rice varieties. Odaebyeo that don’t have any resistance gene to bacterial blight showed susceptible reaction to K1 and K3a. Unkwang, carrying Xa3, showed resistance reaction to K1and susceptible reaction to K3a. HR28021-AC16 was indentified to have the Xa21 gene, which confers resistance to K2, K3,and K3a, while shows susceptible reaction to K1, predominant race in Korea. According to the degree of virulence and the second infection, K3a was more virulent than K1. In yield trial test after inoculation of K1 and K3a, ratio of ripened grain, brown/rough rice ratio, brown rice yield, and milling recovery of head rice were positively correlated with each other and showed negative correlation with protein content of brown and milled rice. Dead kernel of brown rice showed negative correlation with ratio of ripened grain and milling recovery of head rice. In the principal component analysis, ratio of ripened grain, brown/rough rice ratio, brown rice yield and milling recovery of head rice showed opposite direction with dead kernel of brown rice and protein content of brown and milled rice by first principal component. HR28021-AC16, carrying Xa21, showed the susceptible reaction to K1 such as the reduction of ratio of ripened grain, brown/rough rice ratio, brown rice yield, and milling recovery of head rice and the increase of opaque kernel of brown rice, while showed the resistant reaction to K3a. Although Xa21 can improve the resistance to K3a, it would be desirable to breed pyramided varieties with Xa21 and other genes, which can complement the resistance to K1.