Bactrocera dorsalis Dominance and First Report of Three Dacus Species in Uganda

Fruit flies (Tephritidae) significantly threaten mango production and export in Uganda because of direct fruit damage and frequent export rejections, respectively. Accurate species identification is crucial for effective pest management. In Uganda, previous studies relied solely on morphological identification, making it difficult to identify cryptic species. Our study integrated morphological and molecular techniques to assess fruit fly diversity during the May-August 2023 mango season. Surveys were conducted across 20 mango farms in seven districts within Uganda’s two main mango-growing agroecological zones. A total of 256,107 fruit flies were trapped using food baits and para-pheromone lures targeting male Bactrocera, Ceratitis, Dacus , and Zeugodacus species. Morphological screening was performed at the Crop Science Laboratory of Makerere University Agricultural Research Institute, Kabanayolo, PCR confirmation at COVAB’s RTC lab, and Sanger sequencing at Inqaba Biotec. Twenty-one species were documented, ten of which were confirmed to species level: Bactrocera dorsalis, Ceratitis capitata, C. cosyra, C. anonae, Dacus punctatifrons, D. bivittatus, D. eclipsis, D. humeralis, D. armatus , and Zeugodacus cucurbitae . Three species, D. eclipsis, D. humeralis , and D. armatus were reported in Uganda for the first time. The remaining eleven species were identified to the genus level: Ceratitis, Carpomya, Rhagoletis, Dacus , and Zeugodacus. Bactrocera dorsalis was the most abundant (95.5%), dominant, and widely distributed species, followed by D. eclipsis and D. punctatifrons . These findings revealed a high diversity of fruit fly species in Ugandan mango orchards. Further studies and routine molecular surveillance are recommended for comprehensive species monitoring and improved pest management strategies.