The aim of this work has been to unravel the influence of the phytohormone ABA in the molecular mechanisms underlying the postharvest dehydration response and the development and ripening of citrus fruit, taking advantage of the spontaneous fruit-specific ABA-deficient ‘Pinalate’ mutant, which is more prone to dehydration and to develop non-chilling peel pitting (NCPP) than its wild-type ‘Navelate’ orange. Results of the comparative transcriptomic analysis between fruit of both cultivars stored under moderate water stress (70-75% RH, 12 ºC) favouring the occurrence of NCPP highlighted the ability of parental fruit to induce early molecular responses, including both ABA-dependent and independent genes, aimed to reduce water loss and their detrimental effects. ABA application to mutant fruit increased hormone levels and modulated relevant transcriptomic changes related to protein ubiquitination, although did not substantially modify either dehydration rate or NCPP incidence. Additionally, the ABA perception system components in Citrus were identified and their regulation under developmental and stressful conditions increasing ABA in reproductive and vegetative tissues of both cultivars was investigated. Six PYR/PYL/RCAR ABA receptors, five PP2CA negative regulators, and two subclass III SnRK2 downstream protein kinases showed conserved motifs for protein folding, interaction and functionality. Minor differences in the regulation of the ABA receptors and the CsSnRK2s were found, whereas CsPP2CAs levels were lower in the mutant fruit. In addition, ABA receptors and CsSnRK2s gene expression patterns depended on the tissue, the stress severity and the source of the ABA signal from a developmental or stressful stimulus, whilst CsPP2CAs displayed a consistent pattern. Overall results suggest that the ABA-deficient mutant fruit may sense ABA although the hormone signal could be impaired because reduced CsPP2CAs levels causing altered water stress response and higher NCPP susceptibility.