- Fruits: general tree fruits
- Education and Training: demonstration, extension, mentoring, on-farm/ranch research, participatory research, workshop
- Pest Management: biological control
The coffee berry borer is the most economically important coffee pest worldwide. This beetle reduces yields and quality of coffee, resulting in reduced income of coffee growers and the sustainability of coffee producing areas. In this project, the effectiveness of the entomopathogenic fungus Beauveria bassiana was studied at three commercial coffee farms located at different altitudes on the island of Hawaii. The results indicate that B. bassiana occurs naturally in the field, but applications of the commercial fungus should be sprayed early at the fruit development cycle and at the early stages of CBB attack to increase beetle mortality. With monthly applications, the effectiveness of Botanigard® was approximately 20% on average on all of the farms where trials were conducted. Botanigard® was less effective while beetles were in the C position (invasion and damage of the endosperm). Other management techniques, such as regular harvesting and sanitation, must be implemented to keep the coffee berry borer populations under an economic threshold level.
Coffee is one of Hawaii’s highest value agricultural products, ranking fifth in sales among the state’s agricultural industries. Coffee in Hawaii is grown from sea level to 762 meters a.s.l., and the largest contiguous area of production is in the Kona district of the Island of Hawaii (Bittenbender and Smith 1999, HDoA 2013). There are 820 coffee farms recorded in the state of Hawaii, of which 775 are located on the island of Hawaii with 2,549 hectares harvested; the majority of farms are located in the district of Kona. Forty-five coffee farms are located on other major Hawaiian islands, with 1,335 hectares harvested (HDoA 2013), and these contribute significantly to the total value of Hawaii’s coffee production. The farms located in the island of Hawaii are small and independently owned, and production procedures range from conventional approaches to organic production. According to the Hawaii Agricultural Statistics Service (HASS), the total acreage remained unchanged at 8,000 but harvested acreage declined 200 acres to 6,100 (HDoA 2012). The farm revenue for coffee is estimated at $34.4 million (parchment equivalent basis) for 2011/12. The CBB is a major concern for the coffee industry and limited sales are predicted (HDoA 2012).
The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), is a pest of immature and mature coffee berries and is the most economically important coffee pest worldwide due to the extensive destruction of the coffee seed that they inflict (Bustillo et al. 1998, Vega et al. 2009). The beetles feed and reproduce on the endosperm of the seed (Bustillo et al. 1998, Baker et al. 1992, Damon 2000, Vega et al. 2009). The life stages consist of eggs, larva, pupa, and adult and they occur inside the berry. The female lays two to three eggs per day for a period of 20 days. The colonizing female and larvae make galleries in the seed where they also feed. The founder female remains inside the fruit after oviposition until she dies. There is sibling mating among the adult progeny with a 10:1 sex ratio favoring females; therefore, when the new adult females emerge, they are already inseminated and ready to locate another berry in which to continue the cycle. Male insects do not fly and remain inside the berry. The life cycle varies according to the temperature: 21 days at 27°C, 32 days at 22°C, and 63 days at 19.2°C. Females can live 157 days and males may live for 20 to 87 days at (24.5 °C) (76 °F) (Bustillo et al. 1998, Damon 2002, Vega et al. 2009). Three types of damage have been reported; 1) premature fall of young berries, 2) infested ripe berries become vulnerable to fungus or bacterial infection, 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 bean yield losses of 30-35% with 100% of perforated berries at harvest time. Damage can be greater if harvest is delayed (Barrera 2008).
In August 2010, the coffee berry borer was reported in South Kona, Island of Hawaii (Burbano et al. 2011). The infestation has since extended and the beetle is now present from North Kona to the district of Kau, east side of the island and it is severely impacting farms and mill operators. Several farmers have stumped their coffee trees due to the devastating level of infestation. Economic losses for the region have been reported to exceed 30%. 2011 showed a significant increase in CBB damage compared with the 2010 harvest. Reports from the processing mills in Kona estimate the harvest losses to be over 40%. It is only a matter of time the pest finds its way to other Hawaii coffee growing areas on Oahu, Maui, Molokai, and Kauai.
Owing to the fact that the coffee berry borer has only recently invaded Hawaii, management techniques are limited and there is urgency for a strategic plan to reduce populations. The insect-pathogenic fungus Beauveria bassiana (formulated a Botanigard, Mycotrol O)was licensed for use in February 2011 by the Hawaii Department of Agriculture (HDoA). This fungus has shown to cause high mortality of the coffee berry borer in Latin America (De la Rosa et al. 1997). In Hawaii, B. bassiana is sprayed on a calendar basis, without any science-based data upon which to base decisions to make applications. Frequency of application and timing of first applications are thus made arbitrarily. Kona coffee is grown at different elevations, ranging from 213 m to 609 m above sea level, and fruit production is perennial (Bittenbender and Smith. 1999) which facilitates the establishment and reproduction of the coffee berry borer and results in frequent fungus applications as growers are concerned that they will incur complete crop losses. These factors clearly show the need to achieve a greater understanding of the effect of B. bassiana on the coffee berry borer with special reference to timing of applications and the effects of local environmental conditions on the effectiveness of the product.
The objectives addressed by this project were:
(a) determine the effectiveness of three rates of Botanigard® as a control measure for the CBB at different agroclimatic zones in Kona,
(b) determine the effectiveness of Botanigard® upon the position of the CBB female in the coffee berry, and
(c) disseminate and publish the results of this study.