Some Factors Affecting Orange Fruit Splitting of Washington Navel Orange Under Kaferelshikh Conditions. B- The Effect of Climatic Conditions and Fruit Position on the Tree Canopy.

Abstract

This study was carried out during 2010 and 2011 seasons on 14 years old Washington navel orange trees ( C . sinensis L .) grown on two citrus rootstocks ( Volkamer lemon and Sour orange ) and spaced at 5x5 m in private orchard at Kafrelshikh Governorate , to study the effect of the climatic conditions and fruit position on fruit splitting under Kafrelshikh Climatic conditions .The obtained results showed that, the incidence of splitting starts lightly in September coincidence with maximum air temperature and relative humidity before and after this period followed by gradual increase of fruit maturity. Trees on both Volkamer lemon and Sour orange rootstocks gave a high percentage of splitting, reaching a maximum values in November and December. The highest percentage of fruit splitting was counted in the southern aspect and lower part than in upper part of tree canopy. Trees on Sour orange rootstock in both seasons recorded the highest percentage of splitting compared to those on Volkamer lemon.

Pre-Harvest Fruit Splitting of Citrus

“…Splitting increased on the south side of trees in South Africa in 'Washington' navel orange, while the west side had the next highest number of split fruits. Furthermore, the low parts of the canopy had more split fruits than upper parts of the canopy [23].…”