Elsinoë mangiferae

Elsinoë mangiferae, commonly called mango scab, is a biotrophic fungus that infects only mango trees and requires living host tissue to survive. It produces small dark brown or gray spots on the underside of leaves and on fruit that enlarge into textured lesions, and severe infections can cause fruit drop and defoliation and reduce the commercial value of the crop through scarring. First documented in 1943 from specimens in Florida and Cuba, it has since spread and is now considered a pathogen of significant concern to the mango industries of Australia and India; unlike anthracnose, another common mango disease, it infects only young tissue, and fruit becomes resistant once it reaches about half its final size.