First report of strawberry leaf spot caused by Alternaria alternata in Pakistan.
Strawberry (Fragaria × ananassa) has recently become an economically important fruit crop in Pakistan and is cultivated on approximately 1 500 ha each year. A survey of 91 farmers' fields located across Punjab and Khyber Pakhtunkhwa (KPK) provinces and Islamabad (Islamabad Capital Territory), conducted during March and April of 2014-15 and 2015-16, revealed black leaf spot symptoms on strawberry leaves. Leaf spots were irregular in shape, 3 to 6 mm in diameter, and blackish brown. Disease affected yield by reducing active photosynthetic leaf area. Disease incidence was 17 to 55% in visited fields. Based on morphological characteristics, gene sequence analysis and pathogenicity tests, the causal agent was identified as A. alternata. This is thought to be the first report of A. alternata on strawberry in Pakistan.