GA₃ and CPPU synergistically inhibit seed development and promote fruit enlargement in blueberries

Rabbiteye blueberry exhibited merits in environmental adaptation and high yield, but its fresh food quality is relatively poor compared with highbush blueberry because of the numerous seeds contained in the fruits.
In order to obtain large and seedless fruits of rabbiteye blueberry, flowers of rabbiteye blueberry cultivar ‘Baldwin’ were treated with exogenous growth regulators Gibberellic acid (GA₃) and Forchlorfenuron (CPPU), therefore, the pattern of GA₃ processing flowers, the concentration of GA₃ and CPPU, treatment time for flowers by GA₃ and CPPU were studied.
The results showed that the seedless fruit rate by soaking induced with GA₃ was significantly higher than those induced by spraying.
The optimal treatment time for GA₃ is 7 d after full bloom, while that of CPPU is 15 days.
The optimal concentration of GA₃ and CPPU was 100 and 10 mg L^‑1, respectively.
Treating with GA₃ alone can obtain seedless fruits, but the ripened fruit weight decreased by 10.57%. Application of CPPU alone can increase fruit weight, but the fruit contains plump seeds.
After synergistic treatment with GA₃ and CPPU, seedless fruits were obtained and the fruit weight increased by 20.86%. Moreover, there was no significant difference in the soluble solids content and total acid content between the treated and untreated fruits.
It implies that there was no significant change in the taste of blueberry fruit after the synergistic treatment of GA₃ and CPPU. Therefore, the synergistic induction of GA₃ and CPPU had useful effects on obtaining seedless fruits for improvement of the fruit quality of rabbiteye blueberry.

XIII International Vaccinium Symposium

X.M. Wang, X.Y. Ping, L.C. Hu, C.H. Zhang, Y.Q. Wu, W.L. Wu, W.L. Li

rabbiteye blueberry, flowers, gibberellic acid, forchlorfenuron, seedless fruits

https://doi.org/10.17660/ActaHortic.2025.1440.41