Abscisic acid and fruit ripening. Its role in grapevine acclimation to the environment: a case of study

BERLI, F.J.; PICCOLI, P.; BOTTINI, R.

Hormones and Plant Response

Springer

Año: 2021; p. 191 - 209

The phytohormone abscisic acid (ABA) is a sesquiterpene (C15) produced not only in plants, but also by algae, fungi and bacteria. In higher plants, ABA is produced in plastids via the methyl erythritol phosphate that leads to carotene biosynthesis. ABA levels in plant tissues are regulated by biosynthesis, catabolism and reversible conjugation with glucose. Cell site of ABA synthesis is associated with its role in the control of stomata movement. ABA alleviates plant tissues from water stress by inducing stomata closure that hampers water restriction, although CO2 diffusion is also lessened and therefore photosynthesis limited. However, ABA is also critical for growth and yield under non-stressful conditions, and even it promotes growth and cropping under stressful situations and in different species by improving water use efficiency and dry matter accumulation. In fruits ABA participates in their growth, development and ripening, interplaying with other phytohormones and regulating a complex network of transcriptional factors. The control by ABA of grape berry ripening and its role in grapevines acclimation to solar ultraviolet-B and moderate water restriction is analyzed as a case of study. The results obtained involve crop increases as a result of fruit set stimulation, along with modulation in carbohydrate transport, enhancement of membrane stability via sterol biosynthesis, increase of antioxidant enzymes, and promotion of phloem tissue. ABA also induces production of metabolites with antioxidant properties, like phenolic and volatile organic compounds, in berry skins, so anticipating berry ripening and improving the fruit characteristics for high-quality winemaking.