**Abstract**

The technological levels used to reduce fruit losses in post-harvest are closely linked to those used in pre-harvest. Applications of phytohormones, growth regulators, and calcium to fruit in pre- and post-harvest are viable alternatives to increase and preserve quality attributes. Knowledge of the action and response of fruits to the exogenous application of different phytohormones, growth regulators, and calcium in pre-harvest are fundamental when considering that fruit quality is acquired at this stage and that the purpose of post-harvest technology is to preserve fruit quality. This chapter describes research carried out to evaluate the response of different fruits to the application of phytohormones, phytoregulators, and calcium, which showed favorable responses in increasing fruit quality in pre-harvest and preserving quality in post-harvest.

**Keywords:** auxins, gibberellins, cytokinins, ethylene, calcium, fruit, pre-harvest, post-harvest, application, preservation, quality
