Effect of Surround WP®, a kaolin-based particle film on sunburn, fruit cracking and postharvest quality of 'Kandhari' pomegranates

Pomegranate (Punica granatum L.) can suffer from sunburn and fruit cracking, and biotic stresses such as bacterial blight (Xanthomonas axonopodis pv. Punicae) (Hingorani and Singh) Dye and fruit borer (Deuodorix isocrates Fabr.). Because particle film technology has emerged as a promising technology, many kaolin-based films such as Surround WP®, Parasol® and Anti-stress-500®, have been developed. Hence, a study was conducted to observe the effects of Surround WP® on 'Kandhari' pomegranate. For this, five sprays of Surround WP® (3%) were made during the fruiting season of 2015 and 2016 in randomly selected 'Kandhari' pomegranate bushes, starting from June 15, at fortnightly interval every year, in addition to non-sprayed control pomegranate bushes. Observations on biotic, abiotic stresses and quality attributes were recorded after harvesting fruit. The results revealed that pre-harvest sprays of Surround WP® reduced the sunburn and fruit cracking in 'Kandhari' pomegranates by 47% and 46%, respectively, and the incidence of both fruit borer and bacterial blight by 50.3 and 40.2%, respectively. The Surround WP®-treated pomegranates exhibited 46.4% higher cosmetic appeal, developed 19.5% higher red colour, and contained 17.4% higher levels of total anthocyanin content than untreated (control) fruit. Similarly, Surround WP®- treated fruit had significantly higher total phenolic content, antioxidant activity, higher juice recovery (18.2%) and soluble solid content (5.6%) but exhibited nearly 35.9% lower lipoxygenase activity than untreated pomegranates. Thus, this technology has potential to be adopted in pomegranate production.