The Influence of Biostimulants on Tomato Plants Cultivated under Hydroponic Systems

Abstract

Two biostimulants, RutfarmMaxifol (Ascophyllum nodosum extract 17.5%, amino acids, macro- and microelements, Agromaster, Russia) and Radifarm (polysaccharides, glycosides, amino acids, and micro-elements; Valagro, Italy), were applied at different concentrations on tomato plants of the hybrid cultivar ‘Merlice’, grown under a hydroponic system. Biostimulants were applied in the form of seed soaking and twice as foliar sprayings at flowering and at the initial fruit development stages. Biostimulants were applied as water solutions at concentrations of 2.5, 5.0, and 7.5 mg·L−1. Plant growth, productivity, and fruit quality parameters were determined at three points: 35, 70, and 105 days after seeding. All biostimulant treatments resulted in higher values of growth parameters and yield productivity in relation to the control. The application of biostimulants improved the parameters of the fruits’ quality by increasing the total soluble solids and antioxidants, ascorbic acid, and carotenoid contents but it did not affect tomato fruit acidity; therefore, tomato fruits from the treated plants were tastier than those from control.

Innovative Protein Gel Treatments to Improve the Quality of Tomato Fruit

“…The research carried out in this study regarding titratable acidity showed that although there are no significant differences between the experimental variants (Figure 4), the acidity is lower (between 1.13 ± 0.30 and 1.19 ± 0.19 g% citric acid) in the tomato fruit from treated plants than in the control variant (1.38 ± 0.18 g% citric acid). Also, according to Abdelkader et al [33], the acidity rate of the tomato fruit tended to decrease under biostimulant treatment. The low acidity of tomato fruit is involved not only in defining the taste and flavor, but also has an important contribution to food safety by destroying spoilage microorganisms [35].…”

“…The same trend was noted regarding total soluble sugars, which registered an increase of 22% in the V2 sample and 39% in the V3 sample, compared to the untreated sample (Figure 4). Also, Abdelkader et al [33] reported enhanced dry matter of tomato fruit by 14% over control (from 6.35% to 6.85%) under biostimulant treatment. On the contrary, investigating the effect of three biostimulants applied on a tomato crop, Grabowska et al [34] found that there was no clear effect of biostimulants on the dry substance and soluble sugar amount in the tomato fruit.…”

“…Numerous studies on this topic have concluded that the treatments with biostimulants positively impacts plant development by increasing metabolism and inducing changes in biochemical processes, so that fruit with improved quality are obtained. For instance, the research conducted by Abdelkader et al [33] noted an increase in the total soluble solids and antioxidants, ascorbic acid, and carotenoid contents after biostimulant treatment, but it did not influence tomato fruit acidity, so tomato fruit obtained from the treated plants were tastier than those from the untreated variant.…”

Boosting Resilience and Efficiency of Tomato Fields to Heat Stress Tolerance Using Cytokinin (6-Benzylaminopurine)

“…The following parameters were measured at 90 DAT: chlorophyll content (chlorometer), acidity, total soluble solids (refractometer), and ascorbic acid content (vitamin C). Ascorbic acid was measured via methods described by the Association of Analytical Communities, particularly the 2,6-dichlorophenol indophenol titration method, and expressed as mg•100 g −1 FW [37]. To measure titratable acidity (TA), tomato fruits were homogenized with distilled water and then titrated with 0.1 N NaOH.…”

Amino Acids Biostimulants and Protein Hydrolysates in Agricultural Sciences

“…Biostimulants are considered bioactive substances that are either inorganic or organic microorganisms that can increase crop performance when utilized in small quantities [ 1 ] as they can enhance both performance and growth as well as improve nutrient- and water-use efficiencies of different crops [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. Amino acids have a dual function as building blocks for proteins and as providers of organic nitrogen, which can alleviate the negative impacts of drought and salt stress [ 9 ], and promote cell growth. They are vital in metabolite synthesis, growth, and development, and appropriate in plants because of their structure as protein units [ 10 , 11 , 12 , 13 , 14 ].…”