Changes in Antioxidant Content of Tomato Fruits in Response to Cultivar and Nutrient Solution Composition

Abstract

The aim of this study was to investigate the effect of cationic proportions (K/Ca/Mg) in the nutrient solution on fruit quality (quality attributes and antioxidant content) using a high-pigment, 'Lunarossa', tomato cultivar and a standard tomato cultivar ('Corfù') grown in soilless culture. Treatments were defined by a factorial combination of three nutrient solutions having different cationic proportions and two indeterminately growing round tomato cultivars. A high proportion of K in the nutrient solution increased the quality attributes (fruit dry matter, total soluble solids content) and the lycopene content of tomato fruit, whereas a high proportion of Ca improved tomato fruit yield and reduced the incidence of blossom-end rot (BER). The highest total antioxidant activity was observed in the treatment with a high proportion of Mg in the Lunarossa cultivar. The high-pigment hybrid has provided a higher antioxidant content (lycopene and alpha-tocopherol content) than the commercial hybrid, but it was more susceptible to BER and consequently less productive.

Effects of Nitrogen Fertilization on the Phenolic Composition and Antioxidant Properties of Basil (Ocimum basilicumL.)

“…Though nitrogen, phosphorus, potassium, and calcium fertilization levels have been shown to affect the production of secondary metabolites in some plants (20)(21)(22)(23)(24), mineral nutrition has little or no effect on polyphenolic production in others (25)(26)(27).…”

<b>Growth and production of tomato fertilized with ash and castor cake and under varying water depths, cultivated in organic potponics

“…According to Jones Júnior (2005), excess K fertilizers in the nutrient solution reduce the absorption of Ca because K is preferentially absorbed and transported in the plant. Fanasca et al (2006) observed increases in the mass of fruits with blossom-end rot from 0.34 to 0.98 kg per plant with variation of 0.23 to 4.4 in the K:Ca ratio.…”

Nutrient Solutions for Hydroponic Systems

“…Conversely, there are evidences of positive effects of high concentrations of nutrient solution. In salvia, the increase of Hoagland concentration at 200% caused that plants flowered 8 days previous to the plants at low concentrations, increasing total dry weight and leaf area (Kang & van Iersel, 2004 (Fanasca et al, 2006).…”