Characterizing the mode of resistance conferred against Asian Soybean Rust by CcRpp1, a novel R gene from Cajanus cajan (L.) Millsap.

ABSTRACT: Asian soybean rust (ASR), is one of the most significant biotic threats that impacts global soybean production each year. This aggressive soybean disease, caused by the fungal pathogen, Phakopsora pachyrhizi Syd & P. Syd, has resulted in major losses to the soybean crop in Brazil since its first introduction in 2001. Agronomic and chemical strategies are extensively employed to control this disease. Commercial soybean lines that provide broad, durable resistance to ASR are not currently available. The disease resistance (R) gene, CcRpp1 (C. cajan Resistance against P. pachyrhizi 1) has been demonstrated to provide strong resistance against ASR when expressed in soybean. In order to understand better the mechanism or mode-of-action of this gene, we carried out a multi-disciplinary study of transgenic soybean plants containing CcRpp1. Using a combination of cytology, transcriptomics and metabolomics, we show that resistance is expressed rapidly and fungal infection is arrested early, within 24-36 hours after inoculation with the pathogen. At least 2 layers of resistance responses are operational. These responses either serve to suppress normal hyphal growth and differentiation thus blocking eventual haustorial initiation or these fungal feeding structures are sequestered within the host cells and fail to mature. Together these effectively provide immune-level resistance against ASR. The work described here provides novel insight into efficacy of the CcRpp1 gene and lays the groundwork for additional in-depth studies that will lead to the development of sustainable and effective strategies for deployment of durable resistance against ASR.

ORGANISM(S): Glycine max

PROVIDER: GSE217280 | GEO | 2025/01/01

REPOSITORIES: GEO