Improving Fruit Quality of Crimson Seedless by Ethephon and Abscisic Acid Foliar Applications Using Three Machine Types

T HIS study was conducted in two successive seasons 2017 and 2018 on ‘Crimson Seedless’ vines budded on Richter 110 rootstock at four years old, grown in a private orchard at Al Qattah, Giza Governorate, Egypt, to improving fruit quality, especially color. using three Spray machines ( 1- Electrostatic ESS 2- Cima 3- backpack sprayers) and six foliar applications of materials concentration (500ppm Ethephon, 1000ppm Ethephon, 2000ppm Ethephon, 500ppm Abscisic acid, 1000ppm Abscisic acid and 2000ppm Abscisic acid) at veraison. Fruit quality, especially TSS/acid ratio and Anthocyanin content were increased when spraying by ESS followed closely by Cima spray machines. 2000ppm of Abscisic acid gave the significant highest values of Anthocyanin content followed by 1000ppm ABA and 2000ppm Ethephon, while there was no significant differential effect of them on TSS/acid ratio. On the other hand, the firmness decreased when spraying by 2000ppm and 1000ppm from Ethephon and Abscisic acid. Therefore, it can be recommended to get the best color and TSS/acid ratio for berries of Crimson seedless grape should be spraying 1000ppm Abscisic acid or 2000ppm Ethephon at veraison by ESS or Cima spray machines.