EFFECT OF SITOFEX (CPPU) ON FRUIT SET, FRUIT QUALITY OF ANNA APLLE TREES

Efficiency of the synthetic cytokinin (CPPU) (N- (2-chloro-4-pytidyle-N-phenylurea) was studied on Anna apple trees at full bloom,14 days after full bloom and two time spraying (at full bloom and 14days after full bloom). CPPU tended significantly to increase thepercentage of fruit set, yield and fruiting, while it decreased fruit drop < br />of all treatments. The best results were obtained by 20 ppm CPPU atfull bloom and 10 ppm CPPU two time spraying in the first season.While, the 15 pm CPPU at full bloom was the best during the secondseason.Highest fruit weight, fruit size and fruit dimensions wereobtained by 15 ppm concentrations at 14 days after full bloom in thetwo seasons. Concerning fruit shape index (L/D), an increase in fruitdiameter than its length due to all conducted CPPU treatments in bothseasons. As well as, acidity and TSS/acid ratio were significantlyimproved as a result of all studied treatments when compared to thecontrol.It could be concluded that, most of studied treatments resulted ina positive and significant effect on most studied characteristics, since(CPPU at 15 ppm at full bloom and 20 ppm at 14 days after full bloomwere the most effective treatments for increasing fruit set and yield aswell as improving the most fruit properties.