ARS | Publication request: Potential of Steinernema carpocapsae (Rhabditida: Steinernematidae) against Hypothenemus hampei in Hawaii (Coleoptera: Curculionidae)

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 16, 2012
Publication Date: N/A

Interpretive Summary: Hypothenemus hampei, the coffee berry borer (CBB), is the world’s most significant insect pest on coffee. Insect-killing nematodes can be mixed with water and sprayed on coffee cherries to control this pest. Sprays could be applied either to coffee berries while they are still on the tree, or they could be applied to berries that have fallen to the ground. We carried out a lab and field test to find out whether sprays of Steinernema carpocapsae would result in significant kill of CBB. This nematode species can be purchased in bulk, mixed with water, and sprayed on a crop as an environmentally friendly biopesticide to control insect pests. In the laboratory test, sprays of nematodes resulted in a 27% kill of adults and a 24% kill of the larvae. In the field test, nematodes were sprayed on infested coffee berries which had been picked then placed on the ground and partly covered with leaf mulch. The sprays resulted in 12% kill of adult CBB and 19% kill of CBB larvae. When plain water was used instead of the water containing nematodes, 4% or less of the insects were found dead. Our results are the first to show that this nematode species has the potential to control CBB in coffee berries.

Technical Abstract: Hypothenemus hampei, the coffee berry borer (CBB), is the world’s most significant insect pest on coffee. Entomopathogenic nematodes (EPNs) are natural enemies which have potential as commercial biopesticides against CBB. For control of CBB, EPNs could either be sprayed on coffee berries while they are still on the tree, or they could be sprayed on berries that have fallen to the ground. We carried out a lab and field test to determine whether sprays of Steinernema carpocapsae would result in significant mortality of CBB. In the laboratory test, sprays of nematodes were associated with 26.6% and 23.7% mortality in adults and larvae, respectively, while mortality was =2% in experimental controls. In the field test, sprays of nematodes on coffee berries partly covered with leaf mulch resulted in 12% and 19% mortality of adults and larvae, respectively, while control mortality was =4%. In several cases, we found evidence that S. carpocapsae was able to complete its life cycle in adult and larval CBB. Our data are the first to show the potential of S. carpocapsae as a biopesticide for CBB in fresh coffee berries.