Fig. 1. Dorsal view of an adult coffee berry borer, Hypothenemus hampei
In August 2010, the coffee berry borer was found in South Kona, Island of Hawai‘i, and its identity was confirmed by Dr. Natalia J. Vandenberg (Systematic Entomology Laboratory, USDA-ARS). The infestation in South Kona extends from north of Kainaliu to south of ‘Opihihale (Hawai‘i Department of Agriculture 2010)(Fig.2), which indicates that the insect has been present in the island for some time. The insect has not yet been found on any other island.
Fig. 3. Coffee berry with two holes made by coffee berry borer
The coffee berry borer female (1.4-1.78 mm) attacks immature and mature coffee berries from about eight weeks after flowering up to harvest season (>32 weeks). Females bore a hole into the coffee berry (Fig. 3) and then construct galleries in the seeds (beans) where the eggs are deposited, followed by larval feeding on the coffee seed (Bustillo et al. 1998, Barrera 2008) (Fig. 4). Three types of damage have been reported: 1) premature fall of young berries, 2) increased vulnerability of infested ripe berries to fungus or bacterial infection, and 3) reduction in both yield and quality of coffee, reducing the income of coffee growers (Damon 2000, Jaramillo et al. 2006). The coffee berry borer can cause yield losses of 30-35% with 100% of berries infested at harvest time. Damage may be greater if harvest is delayed (Barrera 2008).
Fig. 4. Coffee berry borer galleries containing eggs (left), and eggs and larvae (right)
Fig. 5. Life cycle of Hypothenemus hampei.
Fig 6. Coffee berries on the ground are a source of reproduction for the coffee berry borer (A-left), ); old berries can harbor hundreds of coffee berry borers (B-right). Photos: Bustillo et al. 1998. Manejo integrado de la broca del café, Hypothenemus hampei (Ferrari) en Colombia. CENICAFÉE.
The coffee berry borer has been reported from plants other than coffee. This beetle can survive in several other host plants, and has even been reported to reproduce in some of them (Damon 2000); but it is not clear how much reproduction can actually occur outside of coffee, the beetle's primary host. Some of these possible alternate host plants occur in Hawaii, including haole koa (Leucaena leucocephala), black wattle (Acacia decurrens), and red fruit passion flower or love-in-a-mist (Passiflora foetida). However, researchers in Hawaii have to date found only a very low incidence of coffee berry borer in any of these other plants, and feel that wild (uncultivated) coffee plants are a much more serious reservoir beetle populations..
Possible alternate host plants of coffee berry borer
Infestation occurs in berries on the tree, and reproduction continues in berries even if they have fallen to the ground (Fig. 6) and in parchment coffee, provided that moisture content does not fall below 13.5% (Damon 2000). Between harvest seasons, females remain inactive in old berries on the tree or ground waiting for the first rains, which stimulate them to emerge and search for new berries in which to begin the next cycle. Coffee berry borers develop faster on the ground due to less extreme temperatures (Baker et al. 1992). Up to 150 coffee berry borers can be found in a single berry between seasons (Brocarta No. 3, 1993).
The recommendations below relate only to cultural control in the field and in wet and dry mills. The fungus Beauveria bassiana has also recently been approved for use in Hawaii as the products BotaniGard ES and Mycotrol O. Please refer to their product labels for application instructions. Additional information on the use of B. bassiana has also been made available by BioWorks Inc., and by the Kona Coffee Farmers Association. The insecticide Provado (imidacloprid) is used in coffee for control of green scale, but is not recommended here, as it has not been evaluated nor labeled for use against coffee berry borer.
Select qualified personnel
Every farm should have at least one person who can learn the basic facts about the coffee berry borer, assess the infestation levels, and carry out the management techniques as they become available.
It is important that pickers and farmers understand that much of the control of the coffee berry borer depends upon an Integrated Management Program (IPM). In Hawai‘i, sanitation in the field and in the wet and dry mills is important to reduce the spread of CBB.
Manage the coffee berry borer based on the annual stages of coffee production
December through February is the pruning season for most farms in Kona. There are two types of pruning: the Kona style, which prunes one or two verticals each year, and the Beaumont-Fukunaga style, in which all the verticals on the tree are pruned in the same year every three to five years (Bittenbender and Easton Smith 1999). Before pruning begins, remove any remaining berries on the trees before they fall on the ground during pruning.
Research in Colombia has found as many as 3.2 million coffee berry borers per acre (including immature stages and adults) in berries that were not removed before pruning. Reproduction continued after three months of being on the ground. Seventy days after pruning, approximately 80% of the coffee berry borers emerged from the fallen berries, and emergence continued for at least another 80 days (Bustillo et al. 1998).
The coffee berry borer continues breeding in out-of-season berries when the seed is soft (Damon 2000). This means that inseminated females are constantly leaving and seeking berries in neighboring coffee farms (Castaño et al. 2005).
Flowering season and fruit development:
There are several peak coffee-flowering periods in Kona, depending on elevation. At 1,200 to 1,700 ft, where the majority of the coffee in Kona is grown, there are three or more major flowering periods and several minor ones per year. At higher elevations (2,000 to 2,500 ft), there are two or three substantial flowerings, in February, March, and April, plus minor flowerings at almost any time of the year. At lower elevations, flowerings tend to occur only in February through March. Coffee has a prolonged and variable fruiting season, berry growth is slow, and all berries do not ripen simultaneously (Bittenbender and Easton Smith 1999).
Baited traps do not guarantee the removal of the coffee berry borer from the field; however, they do indicate the presence of the beetle in the field.
After harvesting season