Abstract: Luhui 602 is a heat resistant and highpower recovery line， but has less resistance to the rice blast. Rice blast resistance gene Pi9(t) showed a broad spectrum of strong resistance. In order to improve the resistance of Luhui 602， Oryza minuta which has Pi9(t) gene was carried as the antisource， and Luhui 602 as the recipient and transmigrate parent through hybridization and resumption of diplomatic relations， and made it selfhybrid until BC3F1. The marker PB8 tightly linked to Pi9(t) was used to select in the separate groups combined with plant type， grain type， maturity and other agronomic traits similar to strains with Luhui 602. In BC3F4， 15 plants were obtained with homozygous Pi9(t) gene and similar agricultural features to Luhui 602. Background selection was carried out with 120 pairs SSR primers， and six plants were screened out as the improved line of Luhui 602. Resistance of these 6 improved line were identified use 32 blast isolates collected in Sichuan Province， and the resistance frequency were 75.00%-87.50%， which identified that the resistance gene had been imported in Luhui 602 successfully and expressed．

Key words: rice blast resistance gene Pi9(t), molecular markerassisted selection(MAS), identification of resistance, Luhui 602