Enhancing of Fruit Set %, Yield and Fruit Quality of “Washington” Navel Orange by Different Agrochemical Foliar Sprays in Application Times

Abstract

The present investigation was conducted at private orchard at Barshome Kalyoubeya Governorate Egypt, on Washington Navel orange trees at fifteen years old during (2019 and 2020) seasons. This objective was to study the effect of foliar spraying trees by three recommended doses of commercial liquid (Berelex), (Dotra CATY-BOR), (Microfalcon) and control (water only), on June drop, fruit set,
yield and fruit quality in two different times by groups. The first group was spraying only once at (full bloom), the second group was sprayed twice at (full bloom and at marble stage). The trees which were sprayed two times gave the highest values than trees which sprayed once and the control in most parameters. Spraying GA3 at 75 ppm two times was more effective in reducing fruit drop (June drop), peel thickness and acidity. Farther more it, enhancing initial fruit set %, final fruit set retention %, fruit weight, juice volume and VC with significant increase in yield as number of trees or as Kg/tree. The minimum values were obtained by the control. So according to previous results, foliar spraying of GA3 at 75 ppm twice at full bloom and the marble stage of 'Washington orange' trees can be recommended.