Conservation Biological Control of Coffee Berry Borer by Applying Nitrogen Fixing Tree Mulch to Enhance Indigenous Entomopathogenic Nematodes

View the project final report

Commodities

• Additional Plants: coffee

Practices

• Crop Production: agroforestry, alley cropping, Reduced pesticide use
• Education and Training: demonstration, extension, workshop
• Natural Resources/Environment: Improve soil health
• Pest Management: biological control, mulches - killed
• Production Systems: agroecosystems
• Soil Management: organic matter, soil microbiology, soil quality/health

Coffee berry borer (CBB), Hypothenemus hampei, is a world-wide threat to coffee (Coffea
arabica) production, causing more than 35% yield loss if harvest is delayed. Coffee is the second
most valuable commodity crops in Hawaii. Current management practices for CBB include
labor-intensive field sanitation by strip picking cherries and cleaning ground along with multiple
expensive applications of marginally effective Beauveria basssiana. This proposed project aim
at developing a sustainable pest management strategies through inundative augmentation of a
cosmopolitan soil dwelling parasite of CBB known as entomopathogenic nematode (EPN) in the
genus, Heterorhabditis. Based on ecological knowledge on EPN, these nematodes prefer higher
moisture and UV protection, which can be provided by mulching the soil under the coffee
canopy where cherries infected with CBB would fall. Leucaena leucephala hybrid KX2 is a fast
growing nitrogen-fixing tree locally available to farmers that is an ideal mulching materials for
coffee production. Specific objectives of this research are to 1) develop an effective EPN
application method through “CBB bombs” technique using meal worms as a carrier of
indigenous EPNs; 2) enhance the persistence and infectivity of indigenous EPNs against CBB
using mulch of N-fixing tree; and 3) evaluate tree mulch and “CBB bombs” on coffee yield,
quality and economics. Two field trials will be conducted to evaluate if CBB bombs and KX2
mulch can enhance parasitism of EPNs on CBB and improve coffee production. The success of
this project would provide farmers an economically viable option to battle CBB while reducing
fertilizer inputs, avoid intensive labor for sanitation, improving soil health condition through
mulching, and likely lead to yield and profitability increases. Through publication of extension
and peer reviewed articles, YouTube videos, field days and on-farm demonstration, we expect
this project will easily be adopted and utilized by coffee farmers in Hawaii and beyond.

1) Develop an effective EPN application method through “CBB bombs” technique using meal
worms as a carrier of indigenous EPNs.
2) Enhance the persistence and infectivity of indigenous EPNs against CBB using mulch of N‐
fixing tree.
3) Evaluate tree mulch and “CBB bombs” on coffee yield, quality and economics.