Fine-scale infestation pattern of Bactrocera dorsalis (Diptera: Tephritidae) in a mango orchard in Central Mozambique

The production of mango in Mozambique is under threat due to fruit fly infestation, and most of the farmers cannot afford the cost of control. Spatio-temporal dynamic of Bactrocera dorsalis was assessed at farm level in Manica Province to provide information for better calibration of pest management strategies and thereby minimize the use of pesticides and other costs associated to pest control. 64 Chempac Bucket traps baited with torula yeast were monitored weekly at a 10 ha mango orchard. From the species captured on the traps only B. dorsalis were considered for the study due to its importance on mango. A universal spatio-temporal kriging model was fitted to investigate the spatio-temporal pattern of the fly. Results of the analysis showed high spatial heterogeneity of the fly over time, with the occurrence spreading from the margins of the mango orchard and infesting the whole orchard during the period of peak of abundances reaching densities of more than 500 fly per trap per week. These results shows that the flies that infest this particular orchard may come from the marginal area, especially from local varieties which get matured earlier. The findings of this study provides information to be taken into consideration by farmers about when and where apply the control measures.