Abscisic Acid Impacts Tomato Carotenoids, Soluble Sugars, and Organic Acids

Abstract

<jats:p>Plant growth regulators (PGRs) are chemicals used on a wide range of horticultural crops. These exogenous chemicals, similar to endogenous plant hormones, regulate plant development and stimulate a desired growth response, such as control of plant height. One such PGR is abscisic acid (ABA), which has been used effectively to improve fruit quality, specifically sugars and phytonutrients. The purpose of this study was to examine the effects of exogenous applications of ABA on tomato (<jats:italic>Solanum lycopersicum</jats:italic>) fruit quality, such as carotenoids, soluble sugars and organic acids, and ABA on tomato leaf chlorophylls and carotenoids. Furthermore, this study compared how ABA and calcium (Ca) treatments together affect fruit quality and whether there are added benefits to treating plants with both simultaneously. ABA treatments proved effective in increasing tomato fruit soluble sugars and decreasing organic acid concentrations. This study demonstrated that ABA is a viable PGR to significantly improve tomato fruit quality, specifically pertaining to carotenoids, soluble sugar, and organic acid concentrations.</jats:p>

Applications of Abscisic Acid and Increasing Concentrations of Calcium Affect the Partitioning of Mineral Nutrients between Tomato Leaf and Fruit Tissue

“…A study conducted by Pérez-Jiménez et al [31] demonstrated the effect of ABA on mineral nutrient concentrations, soluble sugars, and yield of sweet pepper fruit. Previous research by de Freitas et al [52,53] and 48,51] on how ABA affects Ca concentrations, soluble sugar content, and yield in tomato plants presented opposing conclusions. For example, the work by Pérez-Jiménez et al [31] did not find differences in Ca and soluble sugar concentrations in sweet pepper fruit tissue.…”

“…In recent years, research has demonstrated how ABA influences plant metabolites, such as carotenoids [48,49], flavonoids [50], soluble sugars [49,51], and Ca uptake and distribution [12][13][14]52,53]. A study conducted by Pérez-Jiménez et al [31] demonstrated the effect of ABA on mineral nutrient concentrations, soluble sugars, and yield of sweet pepper fruit.…”

“…For example, Barickman et al [13,14] indicated that applying ABA as a foliar treatment significantly increased Ca concentration in the distal tissue of tomato fruit and decreased the incidence of BER compared to the non-treated control and root tissue applications. In addition, Barickman et al [48,51] demonstrated that foliar ABA increased soluble sugars such as glucose and fructose in tomato fruit tissue. Thus, even though there may have been decreases in mineral nutrient concentrations in tomato leaf tissue, previous research demonstrated that there were no significant reductions in yield [12][13][14].…”

Effects of Exogenous Abscisic Acid (ABA) on Carotenoids and Petal Color in Osmanthus fragrans ‘Yanhonggui’

“…In a previous study, it was reported that ABA treatment mainly increased the β-carotene and lutein content in the leaves of tomato [20]. In the fruit tissue of tomato, the β-carotene content was also increased by ABA treatment [19]. Lutein and β-carotene contents were also higher in ABA-treated plants than in control plants in Chinese cabbage and turnip [29,30].…”

“…In addition, the application of exogenous ABA has been shown to affect carotenoid content in Lycopersicon esculentum, as ABA treatment decreased the content of lutein but significantly increased the content of β-carotene. In two additional species of tomato, the application of ABA increased lutein, β-carotene and zeaxanthin in their leaves [19,20]. Correlated with the change in carotenoids, the expression of genes involved in the metabolic pathways of carotenoids was also influenced by ABA treatment.…”