Organic acids combined with Fe-chelate improves ferric nutrition in tomato grown in calcisol soil

Abstract

Plants developed in calcisol soils have limitations in iron nutrition, so exogenous applications of organic acids plus iron chelate can be an alternative. With the objective of knowing the answer of adding organic acids in the fertilizer solution plus a ferric chelate on the characteristics of the ferric nutrition of tomato plants developed in the calcisol soil the present experiment was established. We conducted the experiment in two stages, in the first stage studied different concentration of some organic acids: citric acid (CA), oxalic acid (OA), salicylic acid (SA), and humic complexes (HCs) combined with a FeEDDHA iron chelate, we included treatment control FeEDTA and FeEDDHA and treatment without iron in the fertilizer solution. In the second stage, we compared the best concentrations of organic acids in combination with FeEDTA iron chelate; we used to treatment control FeEDTA and FeEDDHA, and a control treatment without iron in the fertilizer solution. The best concentrations were CA 10 −4 M, OA 10 −4 M, SA 10 −5 M, and HC 0.4 ml l −1. In the second stage, the addition of CA+FeEDTA and HC+FeEDTA increased SPAD units, chlorophyll and vitamin C contents and fruit quality improved. An increase content of Fe, Zn, and Mn in leaves was presented with treatment CA+FeEDTA and HC+FeEDTA. Addition of CA+FeEDTA improved the oxidation-reduction potential, pH and electrical conductivity (EC) of plant leachates, followed by HC+FeEDTA. Applications of CA and HC in the nutrient solution in combination with EDTA-type chelate improved the characteristics of the ferric nutrition of tomato plants developed in calcisol soil.

Iron Supplement-Enhanced Growth and Development of Hydrangea macrophylla In Vitro under Normal and High pH

“…In order to prevent Fe deficiency and assist in coloration, the suggested substrate pH range is 5.2 to 5.6 for greenhouse cultivation of H. macrophylla [47]. For Calcisol soil, only adjusting pH is not a good way to reduce the chlorosis, organic acids such as citric acid (CA), oxalic acid (OA), salicylic acid (SA), or humic complexes (HCs) combined with Fe chelate improved the quality of tomato [48]. In this study, the Fe accumulation in plantlets was promoted by a lower pH.…”

Effects of Citric Acid and Humic-like Substances on Yield, Enzyme Activities, and Expression of Genes Involved in Iron Uptake in Tomato Plants

“…The exogenous application of citric acid in nutrient solution was found to increase leaf tissue Fe content in tomatoes potted in calcareous soils [21]. Citric acid improves Fe bioavailability by converting Fe to its plant-available form [22].…”

“…However, these products can be lost by leaching or adsorbing on the soil particles because of the high pH values and high carbonate content of the soil and because of their high affinity with calcium or magnesium [19]. In this sense, citric acid (2-hydroxy-propane-1,2,3-tricarboxylic acid) and leonardite-derived substances (humic, fulvic acid, and humin) improve Fe nutrition in calcareous soils by increasing Fe availability and optimizing synthetic chelate efficiency [20,21].…”

Iron fortification of food crops through nanofertilisation

“…Plant Fe contents range from 100-500 mg kg −1 of dry weight and is present in two distinct oxidation states such as Fe 2+ (ferrous) and Fe 3+ (ferric). Iron deficiency is a common issue in various crops due to its poor transformation into insoluble Fe(III) oxides and oxyhydroxides, making it inaccessible to plants (Cantera et al 2002;Pérez-Labrada et al 2020). Furthermore, nutrient bioavailability in plants relies on their relocation into edible parts and nutrient retention during downstream postharvest processing.…”