Life Cycle Study of Bactrocera invadens, Ceratitis cosyra and Ceratitis capitata (Tephritidae: Diptera) and Assessment of Their Damage to Mango, Guava and Citrus in Shendi Area, Sudan

Laboratory study was undertaken at Shendi area, River Nile State, Sudan during season 2007-2008 to determine the Life cycle and sex ratio of three species of fruit flies including Bactrocera invadens, Ceratitis capitata and Ceratitis cosyra. The damage caused by the above mentioned species was determined on fruits of mango, guava and citrus. The life cycle of the three fruit flies revealed that B.invadens immature stages duration and adults' longevity were shorter than that of C. capitata and C. cosyra. The sex ratio was found to be four females to one male for B. invadens and C. cosrya and three females to one male for C.capitata. Damage caused by fruit flies was significantly higher on guava (79.3±5.6 and 326.6±64) for percentage and degree of infestation respectively, than that of mango and citrus (56.0±4.5 and 198.8±36.6) and (28.9±5.9 and 23.1 ±1) respectively. Among the mango varieties tested, the late mango varieties, Shendi and Abusamaka were more susceptible to fruit flies infestation than the early mango varieties, Kitchener and Baladi. Within the fruiting stage of maturity, the ripening stage was found to be highly infested and was the most susceptible stage for flies' infestation.