CABI - Biocontrol News and Information 21(2) June 2000 News

Biocontrol News and Information

September 2001, Volume 22 No. 3

IPM Systems

This section covers integrated pest management (IPM) including biological control, and techniques that are compatible with the use of biological control or minimize negative impact on natural enemies.

Managing the Coffee Berry Borer

The coffee berry borer (Hypothenemus hampei, CBB) is arguably the world's worst insect pest of coffee and has caused heavy losses costing millions of dollars worldwide. It has been spread through trade from its central African centre of origin across Africa, Asia and Central and South America. An innovative project funded by the CFC (Common Fund for Commodities) with supervision of the ICO (International Coffee Organization) and implemented by CABI Bioscience and in-country partners has been working to develop locally relevant and affordable integrated management systems for CBB based on biological and cultural methods. Participating countries include Colombia, Ecuador, Mexico, Guatemala, Honduras, Jamaica and India. The US Department of Agriculture (USDA) is also funding rearing work in Mississippi. Here we highlight major achievements of the project so far.

CBB damage is caused by the female, which bores into coffee berries to lay her eggs, producing legless white larvae that then feed on the beans for up to 3 weeks. The economic damage is twofold:

premature fall of berries and hence total loss of these to production
damaged berries are retained on the tree until harvest, making them of lower commercial value by reducing weight of the bean and downgrading the quality and affecting the flavour of the coffee

As most of the pest's life cycle is passed within the coffee berry, chemical control is difficult. It is also costly (often pushing the cost of production above the value of the crop) and hazardous (endosulfan, generally regarded as the most effective chemical in use, is a Category 1 poison). Natural enemies have been identified in CBB's region of origin in Africa. Two bethylid parasitoid species (Cephalonomia stephanoderis and Prorops nasuta) have been imported into a number of Latin American countries (Mexico, Guatemala, Honduras, El Salvador, Nicaragua, Colombia, Ecuador and Brazil), and at least one has established in each. A braconid parasitoid (Heterospilus coffeicola) has been under study in Uganda under a separate project, but there are no plans currently to introduce it elsewhere. Native pathogens (Beauveria bassiana strains) are locally important as natural controllers in CBB's introduced range and further work on these is planned. So far, though, biocontrol agents by themselves have been at most moderately effective. Biocontrol interest currently is focusing on the eulophid Phymastichus coffea, which is being supplied to countries under this project.

Manual control (picking infested berries) is labour-intensive and hence expensive, but is still the key recommendation for CBB control. The development of more (cost-) effective technologies is seen as crucial. A main feature of this project has been its introduction of Farmer Participatory Research (FPR) to the coffee sector. FPR involves farmers directly in the development and testing of new technologies. This approach has proven successful for solving the complex problems presented by information-intensive management techniques such as IPM in other crops. Developed in rice in Southeast Asia, it has been adapted, for example, for cotton and vegetables, but until now not for coffee. The project has looked at how FPR can help smallholder coffee farmers manage CBB.

Working with Indian Farmers

From India comes news of an IPM package for smallholder coffee growers that reduces CBB infestation from more than 50% to less than 5%. This is cause for celebration not only amongst farmers, for coffee is a key export earner for India and the sector employs 400,000 people directly. Smallholders are responsible for 60% (175,000 tonnes) of total annual production. Coffee is also instrumental in preserving forest ecosystems in traditional coffee-growing areas, while in non-traditional areas it is helping reduce deforestation caused by shift cultivation.

CBB arrived in India in Tamil Nadu in 1990, and spread rapidly through the main coffee cultivation areas of the Western Ghats, which cover southern Karnataka, Kerala and Tamil Nadu. Severe outbreaks with infestation rates of more than 50% were reported in some areas.

Since 1998, the ICO/CFC project in India, implemented by CABI Bioscience and the Indian Coffee Board has used a participatory approach in farm communities. A total of 52 1-ha IPM pilot plots were set up on holdings of different sizes (from one to more than 100 ha) in three CBB-infested areas, Wayanad, Karnataka and Tamil Nadu. The main interventions prescribed for CBB management were:

timely harvest
thorough and clean harvest
collection of gleanings
removal of infested berries
removal of off-season and left-over berries
use of picking mats (placed under the tree to collect the picked berries)
drying coffee to the standard test weight
early disposal of coffee produced
spot spraying of endosulfan where necessary as a last resort
biological control methods
maintenance of trap plants around the drying yard
use of CBB traps

Cultural controls worked best, especially new interventions such as picking mats. CBB incidence was assessed regularly (every 1-2 months) by systematic sampling. The on-farm experimentation provided an insight into aspects crucial to CBB management. This was particularly true in the smallholder sector, where plot owners who participated in prescribed interventions and data collection gained substantial knowledge. Group participatory-style gatherings were held at many IPM plots, to share experience gained in IPM techniques and demonstrate them to neighbouring farmers. The meetings included question-and-answer sessions, practice in field identification, and discussion and reinforcement of IPM technologies to be adopted.

Amongst aspects investigated in on-farm experiments were:

The use of various trap designs and lure combinations. A 1:1 combination of methyl and ethyl alcohol attracted most CBB, with high catches made in some circumstances (in one case 600 in one day). However, a comparison of trap catches with estimates of CBB populations indicated that percentage catch may be very low: in one trial with 109 traps/acre (270/ha) the catch was calculated as only 0.7%.
The extent of emergence of CBB during drying, and migration and reinfestation of nearby coffee trees. The results of life-table experiments indicated that CBB can remain alive through the first week of drying and that significant numbers of CBB emerge from the berries and fly to the five rows of coffee nearest the drying yards. A battery of alcohol traps placed around the yards and regularly serviced during the harvesting season could be an effective procedure to monitor or even protect against reinfestation of plots.
Biopesticide applications. Poor control was achieved in field trials with Beauveria bassiana. Best control of 24% compared poorly with 80% using endosulfan or 70% with chlorpyrifos.

Over the 2 years of the project, 80 bimonthly training and dissemination workshops were held in Kodagu, Chikmaglur, Wayanad and Tamil Nadu zones. Other activities included follow-up extension visits, village meetings, conventions and workshops, training programmes and mass contact and media programmes.

By working in collaboration with researchers and extensionists, smallholder coffee farmers have made progress in CBB management that will lead to improved livelihoods in this sector. The project adapted and built on farmers' pest control knowledge. As a result, not only have CBB levels been reduced to less than 5% in many areas, but in most cases farmers have been able to reduce and even stop use of synthetic insecticides, which has beneficial effects on both health and the environment. It is also clear that significant progress has been made with both confidence-building in farmers to manage CBB and facilitating the involvement of women.

Listening to Colombian Farmers

In Colombia, collaboration between smallholder farmers, extensionists and researchers from the coffee growers federation FNCC (Federacion Nacional de Cafeteros de Colombia) has produced a novel model of farmer-scientist interaction.

Researchers focused initially on getting to know the areas the project was to work in (spread through three departments) and gaining the trust of the farmers. They achieved this through visits with local extension agents over a 4-month period. They then made individual visits to 113 farmers to identify gaps in farming knowledge. Such visits were informal as the scientists met the household and walked over the farm, but the outcome of each visit was used to fill in a pre-designed form.

Participatory Rural Appraisal (PRA) diagnostic sessions were held in each of nine communities to identify problems and solutions, and to 'brainstorm' CBB control ideas to research. This also helped the researchers to assess farmer knowledge. Extension agents subsequently provided farmer training to fill in the identified gaps and this process was evaluated. Finally, agreement was reached on what and how to test. Farmers suggested some interventions, but most were proposed by the scientists, although farmers subsequently modified some of the techniques during testing. The results were presented by farmers in a farmer-scientist workshop. Practical demonstration rather than 'talk and chalk' will be used to train extension agents in the most promising techniques.

At the PRAs, the following were identified as major causes of CBB problems:

old and unproductive coffee trees
groves were reinfested from neighbouring farms where control measures have not been applied
communities were disorganized
control measures were expensive (although exact cost was unknown)
unharvested berries left food for CBB
labour shortage
generalized pesticide applications

Farmers tended to suggest botanical insecticides as novel solutions, which they had heard about from NGOs or other farmers. Cenicafé (the research branch of FNCC) included these in the research agenda, but they proved no more effective than water. However, farmers were enthusiastic about suggesting modifications to the scientists' ideas, mostly to make them easier to implement and reduce cost. Their role was also fundamental in evaluating the suitability of IPM technologies at an early stage. For example:

1. A novel sampling method (a Cenicafé method coded 'EBEL') was rejected as too time consuming. It was both salutary and useful for scientists to get such advance critique before more time was spent in finalizing an ultimately inappropriate technology.
2. Farmers were initially enthusiastic about equipment designed for trapping CBB in coffee groves, and these were trialed by 39 farmers, who put 1-5 traps in each productive plot. But the traps turned out to be difficult to service (the alcohol lure evaporated quickly, the water was smelly to change and counting trapped CBB was unpopular). CBB populations were relatively low during the experiment so few were caught and many farmers abandoned the traps.
3. Farmers adopted and continued to use trap covers in coffee washing stations, which prevented CBB escaping from harvested berries and reinfesting neighbouring groves. A group of 45 farmers was shown how to modify their processing equipment by covering parts of it with plastic covers smeared with axle grease, engine oil, etc. These proved highly effective. They were easy to monitor and service, and trapped thousands of CBB. Adoption of this measure rose to 80% of participating farmers in the next 18 months.

Farmers were demonstrably enthusiastic about the participatory approach to solving CBB problems, and felt encouraged to continue experimenting. They organized themselves into small groups (with often inspirational names) for this purpose. Scientists, on the other hand, gained knowledge of farmer conditions. For example, they now understand the value farmers place on their own time and labour, and this will inform their research in the future.

The project has also had a positive effect on community interaction (identified as a problem in the PRA). Whether this can be sustained and whether the lessons learned can be applied more widely are questions currently being addressed.

The results so far, however, are encouraging. Although many ideas originated by participatory research do not work, failures are generally identified early on, and only a few are taken through development to final product. This, however, is more efficient in time and money than developing and promoting a smaller number of scientist-originated technologies that may be, but more often are not, ultimately adopted.

Natural Enemies: Many Hands

Collaboration between countries has been the key to making advances in parasitoid rearing and release, with the result that more than one million Phymastichus wasps have been released in Colombia, 300,000+ in Honduras, 200,000+ in Guatemala and 6000+ in Mexico. In Ecuador, first releases were carried out in April 2001, after delays due to flooding. Cultures have also now been established in Jamaica, and releases are expected to begin soon.

Joint work by the US Department of Agriculture (USDA) laboratory at Starkville, Mississippi and staff from the Colombian project is leading to methods for rearing large numbers of both host and parasitoid with low labour costs. Whether the costs are sufficiently low to make augmentative releases economically feasible will be assessed before the end of the project.

USDA has been the key partner in developing automated, artificial diet-based rearing methods for CBB. A pilot facility run by Dr Portilla (seconded from Colombia) now produces 30,000-50,000 adult CBB per day and could produce more if this becomes necessary. Cenicafé maintains a strong culture of Phymastichus in Colombia and has supplied Ecuador, Honduras, Guatemala and India with shipments. Parasitism rates of 60% have been achieved during rearing using a semi-artificial diet including industrial agar as a substrate for CBB hosts (compared to 70% in coffee beans). A successful method to automate collection of CBB from artificial diet has also been developed.

More than one million wasps have been released in Colombia. Although parasitism rates recorded so far are low (0-28%; mean 6.3%), so are CBB populations (3% falling to 2.5% post-release). But there is evidence that the wasps have established and are in at least the third post-release generation.

The Colombians have also provided shipments of Phymastichus to other countries, and training for their staff. As a result, cultures of Phymastichus have been established in Ecuador, Guatemala, Honduras, Mexico, Jamaica and India. Encouraging releases totalling more than half a million wasps altogether have been made in Ecuador, Guatemala and Honduras. Jamaica has made excellent progress on culturing and releasing Cephalonomia, as a result of close collaboration between the Jamaican Coffee Board and CARDI, and is progressing with Phymastichus. In 2000, releases of 50,000 Cephalonomia were made at three sites in the Blue Mountain region.

From Guatemala comes evidence that Phymastichus is adapting to field conditions. Field studies were conducted on a 10-ha plot of arabica coffee at 700 m above sea level (masl) with 40% shade cover and 16% infestation of CBB; 10,000 wasps were released at the central point of each plot. Samples taken at 15-day intervals indicated rapid dispersal over the 10-ha plot in 90 days. Further studies on adaptability indicated a relatively high level of parasitism, with 46%, 15% and 23% recorded at 700, 850 and 1040 masl; in robusta plantations parasitism rates of 21-33% were recorded. Such high rates of adaptability and dispersal are encouraging.

A possible new indigenous biocontrol agent has been found in Honduras; a eulophid, Horismenus sp., was identified as an adult endoparasitoid.

Management of Phymastichus rearing and experimentation by countries has been demonstrably extremely productive in Latin America. There is clear evidence that training has been effective and as a result an enhanced capacity in culturing, release and evaluation of parasitic wasps has been created in the region.

The project is due to finish at the end of 2001, and a final workshop will be held in London in May 2002 to evaluate and disseminate the outputs. At this stage it seems clear that most of the objectives of the project will be met. However, because of the deep and continuing coffee crisis the sustainability of many of the project activities is in doubt. During the remaining months of the project, intensive efforts will be made to look for ways to build on the work of the project.

Contact: Peter Baker,
CABI Bioscience UK Centre,
Bakeham Lane, Egham,
Surrey TW20 9TY, UK
Email: p.baker@cabi.org
Fax: +44 1491 829100