Pilot Testing of an Area-Wide Biological Control Strategy against the Coffee Berry Borer in Colombia Using African Parasitoids

SIMPLE SUMMARY: The coffee berry borer (CBB), so called “broca del café”, is originally from Africa and invaded Colombia in 1988. Classical biological control was attempted through the importation of African parasitoids, but after repeated releases, most of the parasitoid species did not become established. The objective of this research was to determine if releases of the parasitoid Prorops nasuta in CBB dispersal coffee plots, followed by releases of the parasitoid Phymastichus coffea in CBB colonization coffee plots within coffee farms, could lead to an overall decrease in the damage caused by this pest to coffee berries. The results showed that CBB populations decreased from the dispersal, and in the colonization coffee plots, resulted in lower levels of CBB infestation in coffee berries in the field and reduced crop loss. Well-timed and targeted release of these African parasitoids could be used in an area-wide control program against the CBB to lower population levels, reduce crop damage, and replace the use of chemical insecticides in an integrated pest management (IPM) program. ABSTRACT: The coffee berry borer (CBB), Hypothenemus hampei (Ferrari, 1867) (Coleoptera: Curculionidae: Scolytinae), native to Africa, is a major global insect pest of coffee. It has invaded many coffee production areas around the world that do not have natural enemies. In this study, two African parasitoids, Prorops nasuta Waterston (Hymenoptera: Bethylidae) and Phymastichus coffea Waterston (Hymenoptera: Eulophidae), were mass-reared for field release against H. hampei in Chinchiná, Colombia. More than 1.5 million wasps of each species were released on a 61-hectare coffee farm in replicated plots, resulting in parasitism rates of up to 7.7% for P. nasuta and 56.3% for P. coffea. This led to a maximum reduction in H. hampei field populations of 81% from dispersal coffee plots (old coffee crops before plant stumping) and 64.3% in colonization coffee plots (new coffee crops with active growing and fruiting plants) within the farm. As a result of this area-wide strategy, the percentage of CBB-infested coffee berries in colonization coffee plots decreased from 51.1 to 77.5% compared to coffee plots without parasitoid releases. This approach offers a promising alternative to the use of chemical insecticides and could be integrated into current pest management programs to control H. hampei.