Influence of Kaolin Sprays on Fruit Quality and Storability of Balady Mandarin

Ali E. Zaghloul , Hassan A. Ennab, Mervat A. El-Shemy

The present work was conducted in a private orchard situated at Motobus, Kafr El-Sheikh governorate, Egypt during  2014- 2015 and  2015- 2016 seasons. The main objective of this study is to evaluate the effect of kaolin foliar applications on disorder fruits, yield, fruit quality and storability of Balady mandarin fruits (Citrus reticulate,B) for 45 days. Trees were sprayed with kaolin at five  concentrations (0, 1, 2, 3 and 4% ) for three times in summer. Fruit samples were divided into two groups and stored at  2±10C and  6±10C at 90-95%  RH for 45 days.

Results showed that, kaolin foliar applications led to increase yield (as number, weight and (kg) of fruits/tree), reduced fruit disorders and improved fruit quality, moreover, it recorded the highest peel fruit firmness, acidity level, soluble solids content (SSC %) and vitamin C content at harvest time. The highest level of kaolin spray (4%)significantly enhanced such trials compared to control and the other kaolin concentrations.

In addition, kaolin foliar application at 4 % were the most effective treatment in maintaining fruit quality of  Balady mandarin fruits during cold storage at the two storage temperatures (2±10C or at 6±10C) for the two seasons, which significantly indicated by reducing  weight loss and decay as well as chilling injuries percentages. Also, kaolin treatments at (4 and 3%)  recorded the highest values of peel fruit firmness, high levels of SSC, acidity and vitamin C contents compared to the other treatments till the end of storage period, with no significant changes in SSC/acid ratio.

Therefore, spraying with  kaolin at 4 % three times in summer months, considered as the most effective treatment in reducing pre-harvest disorder fruits, improving yield and fruit quality at harvest time and maintained good quality and extending storability of Balady mandarin fruits over the other treatments or control  during cold storage at (2±1 or 6±10C).


Kay words: kaolin, Balady mandarin, Fruit firmness, Weight loss, Disorders, Chilling injury and Citrus reticulate,B