مرکز منطقه ای اطلاع رساني علوم و فناوري - The Efficacy of Precooling with Air and Ozone Treatments Against Postharvest Diseases of Pomegranate

Abstract :

The efficacy of gaseous ozone on postharvest diseases of precooled pomegranates cv. Hicaznar was investigated in this study. Harvested fruit were divided into two groups and a group was precooled (PR+) with air for 20 hours, while other group was not precooled (PR-). Fruit were treated with ozone in an airtight chamber made from a polyethylene bag. Fruit treated with ozone were stored in commercially available modified atmosphere bags at 6 C and 90 to 95 % relative humidity for 60 and 120 days. The experiments were repeated in two consecutive growing seasons (2015 and 2016 years).The data obtained from the evaluations performed on 60th and 120th days of the first experiment (2015) and 60th days evaluation of the second experiment (2016) showed that ozone treatments at doses of 4200,5000 and 8100 C x T (concentration as ppm x time as sec.) reduced decay incidence of fruit although caused phytotoxicity on fruit at ranges classified as week (1), moderate 82) and severe (3), respectively. The ozone treatment at a dose of 3500 C x T on precooled fruit significantly reduced the decay incidence without any visible phytotoxicity in both growing seasons in 120th days. The data obtained from the fruit harvest in both growing seasons and evaluated in two storage periods (60 and 120 days) showed that lower ozone concentrations were able reduce the decay incidence significantly on precooled fruit compared to that of none-precooled fruit. These results showed us that precooling increased the efficacy of ozone treatments. All ozone treatments reduced the microorganism population significantly in fruit calyx.