Effect Of "Ethrel" On Colour Development And Juice Quality Of Sweet Oranges And Grapefruits

Abstract

"Ethrel" was sprayed at 0,120, 420 and 480 ppm on sweet orange and grapefruit trees at fruit maturity stage to improve colouring and juice quality. Changes in fruit colour were observed in both varieties but the results were more conspicuous with oranges than with grapefruits. Following treatment juice quality of oranges was improved significantly, while the effect on grapefruits was not clear. It can be recommended that spraying with "Ethrel" at 120 or 240 ppm on orange trees under the Gulf area conditions may have a profound effect on fruit colouring and juice quality, and may even evade the excessive defoliation resulting from spraying with the highest concentration (480 ppm).