Effect of foliar iron application on anthocyanin genes expression during of developmental stages in strawberry fruit

Anthocyanins are important compounds in strawberry fruit quality. There are different genes involved in the production and accumulation of these metabolites. The aim of this study was to investigate the effect of foliar application of iron, determine the optimal concentration and study its effect on the expression pattern of genes involved in the biosynthesis of anthocyanins of strawberry fruit of Camarossa cultivar during developmental stages. The experiment was factorial based on a randomized complete block design with three replications. So that, first in a preliminary experiment strawberry plants were sprayed with 14% iron chelate at concentrations of 0, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, and 2000 µmol/L. Then properties were evaluated after foliar application. According to the results, fruits sprayed with iron at a concentration of 1400 μmol/L showed the highest level of total anthocyanin. Also, the application of selective concentrations of iron accelerated the ripening of fruits, which in the end, a concentration of 1400 μmol/L was considered as the optimal concentration. Increased expression of FaSUT1, FaMYB1, FaPAL, FaCHS genes and decreased expression of FaMYC1 gene in fruits treated with iron chelate 14% at a concentration of 1400 μmol/L can be a reason for increased accumulation of anthocyanins. Therefore, in order to produce strawberry greenhouses and cultivate them in a soilless environment, according to the results of this study, in order to increase anthocyanins contents, a concentration of 1400 μmol/L of iron can be suggested by foliar application.