Severity of panicle blast on Sasanishiki near-isogenic lines after inoculation with avirulent isolates of rice blast fungus and disease suppression by pre-inoculation

Abstract

To evaluate the efficacy of multilines in rice blast control, panicle blast severity was evaluated for Sasanishiki near-isogenic lines after inoculation with a virulent isolate with or without pre-inoculation with an avirulent blast isolate. Disease severity generally differed among lines, high for Sasanishiki BL No.6, moderate for No.3 and low for No.4. The disease on Sasanishiki BL No.4 was suppressed when panicles were pre-inoculated with a high concentration of an avirulent spore suspension (2.5×10⁶spores/ml). However, this suppression was not observed on Sasanishiki BL No.3 or No.6.