VvARF19 represses VvLBD13-mediated cell wall degradation to delay softening of grape berries.

Fruit softening directly impacts its storage life, transportability, and customer acceptance. Auxin plays a key role during fruit ripening, but the underlying mechanisms of how auxin regulates fruit softening remain unclear. In this study, we investigated the regulatory roles of auxin on berry cell wall degradation during grape ( L.