FaNAC29: a novel gene positively regulating strawberry powdery mildew resistance

Powdery mildew (PM) of strawberry (Fragaria × ananassa) is a prevalent fungal disease affecting all aboveground tissues, especially leaves. Currently, there are few germplasm resources of strawberry resistant to PM, and the resistance mechanism remains unclear. This study constructed a BC₁F₁ segregating population by crossing the highly resistant 'Parajatan' with the susceptible 'Benihoppe'. Using multi-omics approaches, including RNA-seq, QTL-seq, and metabolomics analysis, a key gene FaNAC29 was identified. Subcellular localization revealed FaNAC29 nuclear expression, and transcriptional activation assays confirmed its activation activity. Notably, functional assays revealed that FaNAC29 confers enhanced PM resistance in strawberry seedlings. We further identified the downstream target gene FaPR4 and the interacting protein FaZHD11, using DAP-seq and Y2H assays, respectively. We characterized FaPR4 as a direct downstream target of FaNAC29, which enhances strawberry PM resistance via the modulation of chitinase activity. These findings provide a theoretical basis for breeding strawberry varieties with both excellent commercial traits and PM resistance.