A leaf spot disease was observed on Aloe vera plants as small, circular to oval dark brown necrotic sunken spots on the leaves. Infected tissues collected from different sites in diseased fields were cultured on malt extract agar medium, and the pathogen was identified as Alternaria alternata on the basis of morphological and cultural characteristics. The fungus produced effuse, olivaceous black colonies with dark olive-green margins, and abundant branched septate, golden brown mycelium. The conidiophores were branched, straight, golden-brown, smooth-walled, measuring up to 60 m long by 3 m wide with one conidial scar. The conidia were obpyriform, golden-brown, smooth-walled, produced in long branched chains, with a short pale beak. Pathogenicity tests conducted on healthy potted aloe plants in a glasshouse showed typical leaf spot symptoms after four to seven days. This is the first report of a leaf spot disease of A. vera in Pakistan.
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