Effect of 2,4-dichlorophenoxyacetic acid and gibberellic acid in delaying pre-harvest drop and rind senescence on Ellendale mandarin fruit

Abstract

2,4-dichlorophenoxyacetic acid (2,4-D) was applied alone at 10 ppm and in combination with 10 ppm gibberellic acid (GA) at 10 ppm and 20 ppm, to mandarin fruit cv. Ellendale. Gibberellic Acid was also applied alone at 1O ppm. Sprays were applied either at break colour (10 to 15% yellow) or at full colour. Application of 2,4-D reduced fruit fall before harvest and when combined with GA, the chemicals were not antagonistic. The later time of application of chemicals (full colour) was more effective.