Infestation and evaluation of damage of the Mediterranean fruit fly (Medfly), Ceratitis capitata (Wied.) (Diptera: Tephritidae) on Citrus in Southern Tunisia

The damages caused by the Mediterranean fruit fly (Medfly), Ceratitis capitata (Wied.) (Diptera: Tephritidae) were assessed on citrus host fruits namely: Thomson (Citrus sinensis (L.) Osbeck),  clementine (Citrus clementica Hort. ex Tan.), mandarin (Citrus delisiosa L.), bitter orange (Citrus aurantium L.) and lemon (Citrus limon (L.) Eureka) in two regions in southern Tunisia (Gabes and Tozeur) during 2013-14 - 2015-16. Damage were evaluated by the determination of percentages of fruit infestation (Percentage of punctured fruits) and of fallen fruits. Results showed that C. capitata damage varied upon citrus species and sites. The infestation rates were 42. 02, 39.83, 32.5, and 3.44% in Tozeur, against 39.86, 37.18, 30.57, and 3.38% in Gabes, respectively for Thomson, clementine, mandarin, and lemon. Besides, the highest percentages of dropped fruit were obtained for Thomson navel variety (9.02 and 7.84% in Tozeur and Gabes, respectively) against the lowest percentage recorded for the lemon Eureka variety (2.89 and 2.77% in Tozeur and Gabes respectively). In addition, the highest mean number of punctures/fruit was observed for Thomson navel variety in both regions with mean values of 3.17 and 3.38 %, respectively for Gabes and Tozeur. Results highlighted the severity of C. capitata damages in southern Tunisia and the urgency to develop appropriate control strategies in the oasis fragile ecosystem.