Silencing a Grapevine Gene Boosts Natural Defense Against Powdery Mildew

Powdery mildew hurts grape yields all over the world. Researchers know that silencing a PLL gene in a model plant can create resistance, but they didn’t know if the same gene works in grapes.

To test this, they introduced an artificial microRNA that shut down the grape version of the gene, VvPLL3, in Chardonnay vines. After two days, the vines showed stronger leaf defenses and the fungus made far fewer side branches, which reduced its overall success.

RNA‑seq analysis revealed that 41 genes were turned on or off. The altered genes were linked to pathways that produce defense chemicals, stress‑related transcription factors, specific amino acids, and carbohydrate metabolism. The vines also showed a different mix of neutral sugars in their cell walls.

This means that when VvPLL3 is quiet, other defense routes step in to protect the plant. The findings give breeders new targets to improve natural resistance to powdery mildew.