Effect of foliar nutrition with calcium, boron, and potassium on amelioration of aril browning in pomegranate (Punica granatum cv. ‘Rabab’)

Aril browning is a serious physiological disorder and major fruit quality anomaly in red-coloured pomegranates, under environmental stress such as temperature extremes. In this study, the single and combined effect of foliar nutrition with calcium, boron, and potassium on aril browning in ‘Rabab’ cultivar pomegranate (Punica granatumL.), were evaluated. Experimental factors were foliar nutrition with boric acid (0 and 2 gL−1), – calcium chelate (0 and 20 gL−1) and potassium chloride (0 and 20 gL−1). Results showed that the effect of foliar nutrition with potassium chloride, boric acid, and calcium chelate significantly reduced the browning index by 92.6%. Increment of fruit potassium content had a positive and significant correlation with fruit juice percentage (r = 0.96**), total soluble solids (r = 0.93**), and total acid (r = 0.83**), which had a significant and positive correlation with fruit juice total anthocyanin, phenolic and flavonoid content and negative correlation with the browning index. Foliar application of boric acid and calcium chelates a week before full bloom and four weeks after full bloom and their application along with potassium chloride before fruit ripening can be a new strategy to improve this complication. This recommended strategy could increase export profits by up to 75%.