The effects of pre-harvest and post-harvest parka applications on fruit cracking and storage performance in narince and Italia grape varieties

This study was aimed to determine the effect of pre and post-harvest Parka treatments on the quality change of Narince and Italia grape berries during storage. The experiment was planned according to the complete randomized block design with three replicates and three vines per replicate. The experiment consisted of four treatments: control, Parka application only before harvest, Parka application only after harvest, and Parka application both before and after harvest. The parka applications were made by spraying the vines at a concentration of 1 %30 days before the predicted harvest date in both cultivars. After being exposed to pre-cooling at 5°C for 24 hours, the bunches were stored in a cold storage room for 21 days at 0°C and 85±5% relative humidity. In the samples taken on the 7th, 14th and 21st days of storage, weight loss, decay rate, cracking rate, color values, berry firmness, total acidity, pH, water-soluble solid content, total phenolic compounds, and total antioxidant capacity of grapes were determined. As a result of the data obtained, it was determined that the storable of Italia cultivars was better in terms of criteria such as post-harvest weight loss, decay rate and cracking rate, and Narince cultivars came to the fore in terms of phytochemical content. It has been determined that Parka applications are effective in reducing the cracking rate, but generally do not have a positive effect on the postharvest performance of grape cultivars used in this study.