The symptomatology of blossom end browning (beb) disorder attacking anna apple fruit in Egypt [electronic resource].

Includes references.

The present study was preformed in the two successive seasons 2006 and 2007 to reveal some facts about the blossom end browning phenomenon (BEB) in Anna apple fruits which causes high economic losses of total apple production in Egypt. Mature Anna apple fruits were harvested from six year old trees budded on M.M.106 root stock and grown in sandy soil in a private orchard. The fruits were after harvest immediately stored under room temperature (26°C± 2) and inspected daily up to 10 days to follow up the apparent and histological changes during the incidence of BEB phenomenon. The initiation of BEB which occurred three days after maturity, began with changing in peel color to become strong yellow in nearly circular watery spot, with 1-1.5 cm in diameter located aside of the fruit distal end (blossom end). In the fourth day; the attacked area circularly and slowly spread towards the proximal fruit end axis and also towards the fruit core axis to entailed one fourth of the fruit with" dark yellow" color of peel and flesh. The attacked area extended in the same way to cover one third of fruit mass on the 8th day with "grayish brown" color of the attacked tissue. Moreover, the attacked fruit mass which became more spongy and watery was secondary attacked with many fungal and bacterial micro-organisms on the 8th-10th day after maturity. Regarding the histological aspects, the microscopic inspection of the attacked tissues elucidated that fruit tissues appeared normal and sound for two days after harvesting. On the third day after maturity some cells of the cortex tissue are shown with very thin walls, while some others appeared with deformed cell walls. On the fifth day after maturity, the deformed cells of cortex tissue increased and extended in two axis, those are towards the fruit core as well as towards the proximal fruit end. On the sixth day after maturity, the transverse section showed scattered group of cells in the cortex, which were completely collapsed. The damaged cell walls canceled the individuality of the cells, so that some elliptical grooves and cavities appeared in the cortex. Cell components began to vanish. The results suggested that the deformation of cortex cell walls in the distal part of Anna apple fruit is the first step for BEB incidence.

Summary in Arabic.

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