Document Type : Research Paper

Authors

1 Citrus and Subtropical Fruits Research Center, Horticulture Science Research Institute, Agricultural Research Education and Extension Organization (AREEO), Ramsar, Iran.

2 Citrus and Subtropical Fruits Research Center, Horticultural Science Research Institute, Agricultural Research Education and Extension Organization (AREEO), Ramsar, Iran.

Abstract

Preharvest citrus fruit splitting is a physiological disorder that causes significant damage to producers of susceptible cultivars by reducing the amount of crop available on the market. Proper management of tree nutrition and special attention to the three key elements of potassium, calcium and boron, which are involved in the strength of cell walls and fruit peel flexibility, can be effective in reducing the fruit splitting severity. Therefore, an experiment was carried out in the Ramsar (Citrus and Subtropical Fruits Research Center) during 2018 and 2019 to investigate the effects of foliar application of 1.0% potassium nitrate, 1.0% calcium nitrate and 0.5% boric acid at the end of June drop on reducing the severity of splitting and some fruit traits of Page mandarin. This study was performed according to a combined analysis in time with two factors including years of experimentation and different treatments of foliar application of nutrients, based on randomized complete block design with three replications. The results showed that treatments especially 1.0% potassium nitrate reduced preharvest fruit splitting and increased the yield and improved the quantitative and qualitative fruit traits, whereas had no significant effect on the activity of polygalacturonase enzyme, cell density of blossom-end and navel diameter. Overall, foliar application of nutrients, especially 1.0% potassium nitrate, could be suggested as an effective approach to controlling preharvest fruit splitting and increasing the quantity and quality of Page mandarin fruit.

Keywords