Sphaceloma perseae

Sphaceloma perseae is a fungal pathogen that causes a disease known as Avocado Scab in avocado trees. This disease is prevalent in many avocado-producing regions around the world, including California, Florida, and Mexico.

Overview

The fungus Sphaceloma perseae is a member of the Elsinoaceae family. It is an Ascomycete fungus, which means it produces spores in a sac-like structure known as an ascus. The fungus primarily affects the fruit, leaves, and twigs of avocado trees, causing raised, corky lesions that can reduce the marketability of the fruit.

Life Cycle

The life cycle of Sphaceloma perseae begins when spores are released from infected plant tissue. These spores are spread by wind, rain, or insects to healthy avocado trees, where they germinate and infect the plant. The fungus then grows and reproduces within the plant tissue, causing the characteristic scab lesions. Eventually, new spores are produced and released, completing the life cycle.

Management

Management of Sphaceloma perseae involves a combination of cultural practices and chemical controls. Cultural practices include pruning to improve air circulation and reduce humidity, and removing and destroying infected plant material to reduce the source of spores. Chemical controls include the use of fungicides to protect healthy trees and treat infected ones.

Impact

The impact of Sphaceloma perseae on the avocado industry can be significant. The disease reduces the aesthetic appeal of the fruit, which can lower its market value. In severe cases, it can also reduce the yield of the tree. The cost of managing the disease, including the use of fungicides and the labor involved in pruning and removing infected material, can also be substantial.