Genetic distribution of the avirulence gene AVRPiz-t in Thai rice blast isolates and their pathogenicity to the broad-spectrum resistant rice variety Toride 1     

Katanyutita Damchuay  Tanakorn Srirat  Thanyaluk Sirisathaworn  Apinya Longya  Wattanaporn Teerasan  Piyama Tasanasuwan  Siripar Korinsak  Chatchawan Jantasuriyarat  Theerayut Toojinda 《Plant pathology》2022,71(2):334-343

Rice blast disease, caused by the filamentous fungus Pyricularia oryzae, is one of the most destructive diseases in rice worldwide. Breeding of resistant rice cultivars remains a cost-effective and environment-friendly means for controlling blast disease, but the resistance tends to break down over time because of the pathogen's rapid adaptation. In this study, AVRPiz-t gene sequences of 46 rice blast isolates were evaluated using a Southern blot analysis. The AVRPiz-t gene was present in 24 of 46 (52.2%) rice blast isolates. The pathogenicity assay showed that all blast isolates were avirulent against Japanese rice cv. Toride 1, which carries several rice blast resistance genes including Piz-t, Pii, Pi37, and Pi-ta. Screening for the Piz-t gene in Thai rice germplasm revealed that less than 20% of rice varieties harbour the Piz-t gene. Therefore, the Toride 1 rice variety could serve as an effective donor of rice blast resistance to be used in rice breeding programmes in Thailand. This study provides evidence for co-evolution between the rice blast resistance gene Piz-t and the rice blast fungal avirulence gene AVRPiz-t. Understanding this relationship will facilitate the sustainable development of breeding for rice blast resistance in the future.  相似文献