Fruit fungal diseases are caused by various species of phytopathogenic fungi capable of colonizing plant tissues, especially when wounds, weakened tissues, or favorable environmental conditions are present. These microorganisms can survive among crops in infected plant debris, mummified fruit, soil, bark, plant structures, and other sources of organic matter. Depending on the species, they can produce sexual or asexual spores that are easily dispersed by wind, water, insects, tools, and contact between fruits. Infection usually begins when spores reach the surface of a fruit and find sufficient moisture and a suitable temperature to germinate. The germ tube can penetrate directly into the tissues or take advantage of small lesions caused by bruising, insects, hail, pruning, or abrasions. Once established, the fungus develops a mycelium that grows between cells or on the affected tissues and uses their nutrients to multiply. Some fungi rapidly produce new reproductive structures on the infected areas, generating large quantities of spores that can initiate new infections. Others remain dormant during part of fruit development and become active later, especially during ripening or after harvest. Infections can recur several times during the same growing season, so an initial source of inoculum can lead to rapid spread when high humidity, favorable temperatures, and the presence of susceptible tissues coincide. Survival and dispersal capacity varies considerably among species, but overall, fruit fungi have a high capacity to establish themselves and spread when environmental conditions and the crop's health are favorable.