Evaluation of Some Pomological and Biochemical Characteristics in Malas Torsh and Yosef-Khani Pomegranate Cultivars in Response to Foliar Application of Kaolin

Sunburn is one of the important factors, limiting pomegranate production, especially in regions with hot summers. Since exogenous application of kaolin can increase tolerance to some environmental stresses by improving metabolic pathways and increasing net photosynthesis, this paper studies the effect of kaolin spraying on some pomological and biochemical characteristics of commercial pomegranate cultivars in Rijab region (Kermanshah province). Accordingly, it carries out a factorial experiment, based on a RCBD, which is consisted of three concentrations of kaolin (i.e., 0 (distilled water), 3%, and 6%) as well as two pomegranate cultivars (Malas Torsh & Yosef-Khani) with three replications. Results show that in both cultivars, kaolin treatment at 6% concentration improves fruit weight, the length and width of aril and fruit, aril weight, and the yield. In addition, fruits of both pomegranate trees with kaolin treatment at both concentrations, especially at 6% concentration, show increased soluble solids, fruit juice, and total phenol content. Despite the different morphological and biochemical reactions in the two cultivars, one of the cultivars could be used in accordance to different purposes and conditions. In addition, a high concentration of kaolin reduces sunburn and cracking of pomegranate fruits in both cultivars, increasing yield per hectare. This treatment can serve as a suitable method to reduce physiological disorders in pomegranate growing areas such as Rijab region.