Habitat Manipulation to Reduce Papaya Fruit Fly (Diptera: Tephritidae) Damage: Orchard Design, Use of Trap Crops and Border Trapping

We designed 2 papaya groves to test the concepts of trap cropping and border trapping to control Toxotrypana curvicauda. Intensive fruit sampling in grove 1 indicated that the degree of fruit infestation decreased as the distance from the native vegetation (source of flies) increased. Rows planted 10 m away from the main block of papaya trees (trap crop) exhibited the greatest degree of puncture damage and larval infestation in both experimental groves. Fruit damage was highest after the rainy season was over and was spatially aggregated. We conclude that designing a papaya grove in such a way that a trap crop consisting of plants located 10 m from the main block of trees (and entirely surrounding it) can reduce fly damage significantly. If pheromone-baited fly traps are hung in these peripheral rows, the trap crop effect can be enhanced, and as a result, damage to the commercial block of trees can be reduced even further. Such a fly management scheme should allow growers to avoid or drastically reduce pesticide applications. We discuss our findings in relation to current knowledge of T. curvicauda behavior and make suggestions for further improvement and large scale testing of the management scheme we propose.