Influence of GA3 and boric acid foliar application on bioactive compounds and quality of pomegranate fruit (Punica granatum L.)

Abstract

Purpose: The effect of foliar application of gibberellic acid and boric acid on bioactive compounds and quality of pomegranate fruit cv. Shishe-Kab was investigated. Research Method: This was accomplished through the field and laboratory experiments at the Faculty of Agriculture, University of Birjand, Iran, during 2017 and 2018 seasons. Gibberellic acid (50 and 150 mg L-1) and Boric acid (200 and 600 mg L-1) were applied three times at one-month interval; late in May, June, and July during growth and developmental stages of fruits. The experiment was set in a completely randomized block design. Fruits were harvested at full maturity stage late in October, and physicochemical properties were evaluated. Findings: Results showed that anthocyanin content and antioxidant activity significantly decreased while fruit firmness, ascorbic acid content, and fruit cracking increased in gibberellic acid treatments. Application of 50 mg L-1 gibberellic acid significantly increased total soluble solids content and maturity index, but decreased titratable acidity in the fruits. However, foliar application of gibberellic acid and boric acid did not have significant effects on the pH and phenolic compounds of the fruit. Research limitations: Inability to examine different pomegranate cultivars in the investigation was a limitation. Originality/Value: Pre-harvest foliar use of gibberellic acid and boric acid showed positive and negative effects on postharvest quality attributes of Shishe-Kab pomegranate. Thus, further studies need for practical application.