*Review* **Interplay between Abscisic Acid and Gibberellins, as Related to Ethylene and Sugars, in Regulating Maturation of Non-Climacteric Fruit**

**Fernando Alferez 1,\*, Deived Uilian de Carvalho 1,2 and Daniel Boakye <sup>1</sup>**


**Abstract:** In this review, we address the interaction between abscisic acid (ABA) and gibberellins (GAs) in regulating non-climacteric fruit development and maturation at the molecular level. We review the interplay of both plant growth regulators in regulating these processes in several fruit of economic importance such as grape berries, strawberry, and citrus, and show how understanding this interaction has resulted in useful agronomic management techniques. We then relate the interplay of both hormones with ethylene and other endogenous factors, such as sugar signaling. We finally review the growing knowledge related to abscisic acid, gibberellins, and the genus Citrus. We illustrate why this woody genus can be considered as an emerging model plant for understanding hormonal circuits in regulating different processes, as most of the finest work on this matter in recent years has been performed by using different Citrus species.


**Citation:** Alferez, F.; de Carvalho, D.U.; Boakye, D. Interplay between Abscisic Acid and Gibberellins, as Related to Ethylene and Sugars, in Regulating Maturation of Non-Climacteric Fruit. *Int. J. Mol. Sci.* **2021**, *22*, 669. https://doi.org/ 10.3390/ijms22020669

Received: 17 December 2020 Accepted: 10 January 2021 Published: 12 January 2021

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**Keywords:** abscisic acid; citrus; ethylene; fruit maturation; gibberellins; hormonal interplay; sugars
