Transcription factor AcNAC056 and AcMADS1 regulate gibberellin 2-oxidase gene AcGA2ox1 induced parthenocarpy in Actinidia eriantha

Kiwifruit, as a functionally dioecious fruit crop, necessitates pollination for female plants to achieve fruit set. In this study, exogenous application of the plant growth regulator 2,4-D successfully induced parthenocarpy, resulting in significantly higher fruit set rates compared to natural pollination while producing seedless fruits containing only empty seed coats. Through transcriptome analysis of the flower and young fruit, 10 key candidate genes were identified. We demonstrated that AcNAC056 and AcMADS1 transcriptionally activate AcGA2ox1 expression by binding to its promoter region, thereby elucidating the molecular mechanism underlying 2,4-D-induced seedless fruit formation. Cross-species validation in Arabidopsis revealed conserved expression patterns of AcGA2ox1, AcNAC056 and AcMADS1 following 2,4-D treatment, suggesting conservation of this regulatory mechanism. The study demonstrated that the application of 2,4-D-induced parthenocarpy technology in kiwifruit not only effectively addresses the fruit drop problem caused by insufficient pollination, but also enhances fruit yield. It provided effective technical support for kiwifruit cultivation, demonstrating broad application prospects and significant value in kiwifruit industry. The study contributed valuable insights into the molecular mechanism regulating parthenocarpy in kiwifruit.