Positive relationship between citrus leaf miner and alternaria brown spot

Abstract

Alternaria brown spot, or ABS (Alternaria alternata), is the most prevalent fungal disease of tangerines in the world. Field observations have revealed ABS lesions on leaves wounded by the citrus leaf miner (CLM). Thus, the objective of this study was to assess the relationship between CLM and ABS. Leaves from young Murcott tangor plants and detached leaves from 16 different varieties of tangerines with and without lesions caused by CLM were inoculated with A. alternata. The symptoms of the plants were subsequently quantifed by counting the number of lesions, and the lesion area was estimated using a diagrammatic scale. The presence of CLM damage aggravates the severity of Alternaria alternata fungus infections in susceptible tangerine varieties.