Abscisic Acid: Role in Fruit Development and Ripening

Abstract

Abscisic acid (ABA) is a plant growth regulator known for its functions, especially in seed maturation, seed dormancy, adaptive responses to biotic and abiotic stresses, and leaf and bud abscission. ABA activity is governed by multiple regulatory pathways that control ABA biosynthesis, signal transduction, and transport. The transport of the ABA signaling molecule occurs from the shoot (site of synthesis) to the fruit (site of action), where ABA receptors decode information as fruit maturation begins and is significantly promoted. The maximum amount of ABA is exported by the phloem from developing fruits during seed formation and initiation of fruit expansion. In the later stages of fruit ripening, ABA export from the phloem decreases significantly, leading to an accumulation of ABA in ripening fruit. Fruit growth, ripening, and senescence are under the control of ABA, and the mechanisms governing these processes are still unfolding. During the fruit ripening phase, interactions between ABA and ethylene are found in both climacteric and non-climacteric fruits. It is clear that ABA regulates ethylene biosynthesis and signaling during fruit ripening, but the molecular mechanism controlling the interaction between ABA and ethylene has not yet been discovered. The effects of ABA and ethylene on fruit ripening are synergistic, and the interaction of ABA with other plant hormones is an essential determinant of fruit growth and ripening. Reaction and biosynthetic mechanisms, signal transduction, and recognition of ABA receptors in fruits need to be elucidated by a more thorough study to understand the role of ABA in fruit ripening. Genetic modifications of ABA signaling can be used in commercial applications to increase fruit yield and quality. This review discusses the mechanism of ABA biosynthesis, its translocation, and signaling pathways, as well as the recent findings on ABA function in fruit development and ripening.

Characterization of Highbush Blueberry (Vaccinium corymbosum L.) Anthocyanin Biosynthesis Related MYBs and Functional Analysis of VcMYB Gene

“…In addition, MeJA treatment could induce the expression of MdMYB9 and MdMYB11, whose overexpression in apple callus could improve anthocyanin and proanthocyanin accumulation, and this promotion effect could be further enhanced by MeJA [82]. ABA is considered to be one of the most important positive regulators of the ripening of non-climacteric fruits and anthocyanin biosynthesis [32,83,84]. Karppinen et al [85] found that exogenous ABA treatment could promote the accumulation of anthocyanins in V. myrtillus.…”

Effects of Date Palm Waste Compost Application on Root Proteome Changes of Barley (Hordeum vulgare L.)

“…The upregulation of this gene is related to the increase of ABA activity, correlated to an increase in stress tolerance [ 30 ]. Some ASR proteins function as transcription factors involved in plant response to abiotic and biotic stresses and in several physiological processes such as fruit development and ripening [ 31 ]. Similarly, the expression of ABA related genes such as WRKY transcription factor, trehalose 6-phosphate phosphatase (T6PP), ABA 8′-hydroxylase and protein phosphatase 2C was increased in the root tissue of a tomato due to the application of a tannin-based biostimulant [ 32 ].…”

Plant Development and Crop Yield: The Role of Gibberellins

“…The modulation of fruit traits by the application of phytohormones and plant growth regulators has the utmost relevance in agronomy and a significant economic impact. The molecular mechanisms by which GA influences such traits along with fruit formation are beginning to be understood, showing that the cross-talk of GA with other hormones such as ABA is key in fruit development [ 161 ] and ripening in species such as strawberry [ 162 ]. GA activates ALCATRAZ ( ALC ) genes which govern the fructification process in Arabidopsis [ 163 ].…”