Avocado scab caused by Elsinoe perseae: A diagnostic guide

Avocado scab, caused by the fungus Elsinoe perseae, is a major disease of avocado (Persea americana). Diagnosis of avocado scab is hampered by the similarity that advanced symptoms have with fruit defects caused by other etiologies (e.g., mechanical injuries and insect feeding damage). This diagnostic guide aims to establish key aspects of the identification of symptoms and signs of avocado scab in the field and laboratory, and to provide guidance when conducting isolation, identification (i.e., based on morphological characters, molecular-based assays), maintenance, storage, and pathogenicity tests of the fungus E. perseae.