VviWRKY50‐Mediated Repression of VviPME39 Underpins Gibberellin‐Induced Resistance to Fruit Cracking in Grape

Berry cracking is a severe physiological disorder that compromises quality and causes economic losses in grapes. Despite recent research progress, current knowledge offers limited insight into the molecular pathways. This study shows that gibberellin (GA 3 ) effectively mitigates berry cracking in the susceptible cultivar ‘White Munake’ by modulating cell wall remodeling processes. Multi‐omics analysis revealed that GA 3 treatment significantly alters key pectin‐modifying enzymes and cell wall related pathways. Results showed that VviPME39 , which encodes a pectin methylesterase, facilitates the maintenance of cell wall structure. Functional validation through heterologous overexpression in tomato confirmed that VviPME39 enhances fruit cracking susceptibility and reduces firmness. Furthermore, we identified VviWRKY50 as a transcriptional repressor that directly binds to the VviPME39 promoter and inhibits its expression, proposing a potential novel GA 3 ‐VviWRKY50‐ VviPME39 regulatory module. This pathway operates independently of ethylene‐mediated softening mechanisms reported in other species, revealing a unique hormonal regulatory strategy in grape. Our study showed fundamental insights into the molecular mechanism of berry cracking and identified possible targets for breeding crack‐resistant grape varieties through manipulation of the VviWRKY50‐VviPME39 regulatory mechanism.