Ning Xiao, Yunyu Wu, Xiaoxiang Zhang, Zeyun Hao, Zichun Chen, Zefeng Yang, Yue Cai, Ruyi Wang, Ling Yu, Zhiping Wang, Yue Lu, Wei Shi, Cunhong Pan, Yuhong Li, Changhai Zhou, Jianju Liu, Niansheng Huang, Guangqing Liu, Hongjuan Ji, Shuhao Zhu, Shuai Fang, Yuese Ning*, Aihong Li*. Pijx confers broad-spectrum seedling and panicle blast resistance by promoting the degradation of ATP β subunit and OsRbohC-mediated ROS burst in rice. Molecular Plant, 2023, https://doi.org/10.1016/j.molp.2023.10.001

Abstract

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most important diseases of rice. Utilization of blast resistance genes is the most economical, effective, and environmentally friendly way to control the disease. However, genetic resources with broad-spectrum resistance (BSR) that is effective throughout the rice growth period are rare. In this work, using a genome-wide association study, we identified a new blast resistance gene, Pijx, which encodes a typical CC-NBS-LRR protein. Pijx is derived from a wild rice and confers BSR to M. oryzae at both seedling and panicle stages. The resistance haplotypes of Pijx are determined by gene knocking out and overexpression approaches. Mechanistically, the LRR domain in Pijx interacts with and promotes the degradation of the ATP synthase β subunit (ATPb) via the 26S proteasome pathway, resulting in OsRbohC could not be degraded due to the absence of ATPb interaction, which cause an increase in NAPDH content and ROS burst. Remarkably, when Pijx is introgressed into two japonica rice varieties, the introgression lines confer BSR and yield increases approximately 51.59% and 79.31% compared with the parents in a natural blast disease nursery, individually. In addition, we generated PPL^{Pijx Pigm} and PPL^{Pijx Piz-t} pyramided lines and these lines also confer BSR to panicle blast compared with Pigm or Piz-t-containing rice plants. Collectively, this study demonstrates that Pijx not only confers BSR to M. oryzae but also maintains high and stable rice yield, which provide researchers with new genetic resources and molecular pathways for breeding rice varieties with broad-spectrum blast resistance.

 Molecular Plant, IF=27.5

https://www.sciencedirect.com/science/article/pii/S1674205223003155