Training  for IPM
—Biological Control in Field and Forest
The Strategy of the International Institute of Biological Control

Integrated pest management (IPM) involves choosing appropriate elements from a whole range of pest control techniques (biological, cultural, genetic— i.e. plant resistance, behavioural, mechanical, and chemical) to suit individual cropping systems, pest complexes and local environments. Even where pesticides are included as a last resort as part of an IPM strategy, the emphasis is on rational use: suitable active ingredient selection and careful timing of application with regard to pest population levels. By Stephanie Williamson.

Tropical Forestry Research Programme participants assessing aphid damage in Kenyan conifer plantation. Photo: IIBC

Successful IPM relies on better understanding of the agro-ecosystem and on management skills such as decision-making. Unfortunately, many promising IPM programmes developed by researchers have not been widely adopted because key training and information issues were not addressed. A good example is maize in Latin America. While demonstration plots have shown that IPM programmes can substantially reduce the need for pesticides and produce higher profits, many farmers still spray unnecessarily, endangering both themselves and the environment, in addition to provoking further pest outbreaks. The problem lies in weak extension services, over-complicated technical recommendations, and a failure to involve farmers in research and evaluation processes. Often, the sole source of advice comes from pesticides sales staff.
    Biological control, the use of natural enemies such as predators, parasites and disease organisms to control pest populations, forms the core of any integrated management programme. The International Institute of Biological Control (IIBC), a non-profit organisation, has been working to develop biological control worldwide through research and the provision of information since 1927. In the past our work focused on 'classical' biological control-importing natural enemies from the native range of exotic pests which have been accidentally introduced elsewhere.
    Research, surveying, rearing and release were undertaken mainly by ex-patriate staff on behalf of foreign governments. This kind of assistance is no longer viewed as pro-development, nor are introduced pests the only ones which can be successfully controlled by natural enemies. Appropriate training has therefore become an essential part of IIBC’s work, to be integrated into all projects.

Building biocontrol expertise in the South
One of our most exciting current projects is the Tropical Forestry Research Programme on biocontrol of conifer aphids, which are causing extensive damage in exotic conifer plantations and on certain indigenous trees in eastern and southern Africa. This is a 'classical' programme since the aphids originate from Europe or possibly North America. Kenyan and Malawian scientists took part in the initial surveys for potential natural enemies in the aphids’ native range and were involved from the beginning in ecological research to find the best control candidates and how best to rear them for mass release. They are now transferring research and survey skills to their forestry colleagues in Africa.
    Besides entomologists, training is also geared to forestry technical staff. Representatives from 10 African countries recently received training in biological control principles and release and survey methods. Through funding from British, Canadian and international donor agencies, participating countries will be helped with lab equipment, motorbikes and other basics to set up their own natural enemy rearing facilities. One of the project’s aims is to predict the impact of eventual releases, by monitoring the abundance of pests and control agents. Ugandan entomologists conducted a three day training session on the sampling methods required for forest guards, as part of the skills multiplication side of the programme. The long term goal of the programme is to build a regional network of African specialists with the expertise to handle biocontrol programmes for any forest pest. Another is to raise awareness of biocontrol and IPM among all those employed in the forestry sector.

Encouraging natural enemies in farmers’ fields
IIBC increasingly works with farmers and extensionists to find ways to take advantage of natural enemies already present in the fields. Making people aware of the great variety of control organisms is the first step. Farmers are often extremely knowledgeable about the pest species in their crops but many enemies such as anthocorid bugs, which suck insect eggs, and parasitic wasps, which lay their eggs in pest larvae or eggs, are so tiny they go unnoticed by all except a trained observer. We are producing a poster for extensionists in East Africa showing photographs of the commonly found natural enemies of the African bollworm, and their actual sizes. It will be printed in Swahili too so that small-holders also get the message that heavy pesticide spraying can do more harm than good by killing off these useful insects.
    Drawing on the success of FAO’s Intercountry Rice IPM Programme and Indonesia’s own IPM programme, IIBC’s Malaysian station has been carrying out research on the impact of natural enemies in soyabean in Indonesia since 1991. The difference between this research programme and many previous ones is that trainee IPM advisors and farmers take an active part in setting up the experiments and analysing the results. At Farmer Field Schools farmers judge for themselves the effect natural enemies can have, by putting mesh cages around plants to keep the natural enemies out and watching the pests multiply unchecked. The project showed that some pests, particularly leaf-eaters, are under good natural control and spraying them only wastes money, while others, like the caterpillars and bugs that attack the pods, have few effective natural enemies.
    Once the value of natural enemies is recognised, the second step is to see whether anything can be done to boost their impact. This may involve agricultural practices that the farmer can employ, like leaving certain flowering weeds around fields to provide nectar for adult parasitic wasps. More usually, the farmer times pesticide applications to avoid susceptible stages in the life cycle of a natural enemy, or waits till pest populations reach critical levels before spraying. In some cases it may be necessary to rear up natural enemies in a local augmentation project and release them in the field at a suitable time. For instance, damage caused by stemborers in sugarcane can be reduced significantly by boosting the numbers of a trichogramma egg parasite. IIBC’s Pakistani staff, in conjunction with seven sugar estates, mass rear the wasps which are then released by estate technicians over more than 20,000 hectares of cane.
    IIBC’s training now encompasses a much broader set of people than university-educated entomologists. Most have a general agricultural background and we have found that for many of the crop protection workers it is the first time they have become confident in promoting non-chemical ways to kill pests. Courses in biological control techniques have ranged from one week for Agriculture Assistants and Technicians in Malaysia to one month in the Philippines on biocontrol in rice systems, with plant protection staff from 10 Asian countries. On the Introduction to Insect Pathology for agricultural researchers, participants from 14 African states learnt experimental techniques, mass production methods, and how to formulate environmentally-safe biopesticides using fungi, bacteria and viruses as the killing agent. Customs and quarantine staff also need to know about biocontrol when they handle shipments of imported biological control agents.
    The scope for biocontrol is not limited to farming and forestry: natural enemies are an obvious first choice for controlling unwanted weeds and insects in conservation areas and fragile ecosystems where pesticide use is out of the question. To meet the demand for practical information on how to do biological control in a variety of contexts our training and information group is producing a training manual, which will contain information on the ecological background and step-by-step details of techniques for using natural enemies The manual, to be published later in 1994, is aimed at all those working in agriculture, forestry or nature conservation, and does not require users to have specialist knowledge or scientific training.

IPM for mango mealybugs to cotton bollworms
Much of IIBC’s more recent work is based on integrating natural enemies with other weapons in the IPM armoury.

Sugar
Our experience in sugarcane demonstrates the importance of the right cultural control methods to help, not hinder, natural control. In some areas of Pakistan, stemborer caterpillars can survive in left-over sugarcane burnt incompletely after harvest. Elsewhere, purposely leaving cane trash unburnt works best because a key parasitic enemy of the pyrilla cane-sucking bug lays its eggs on the dry leaves. The parasite populations are much higher in fields where the trash is left. A major lesson from IPM experience has been that there are no blanket solutions: if people are given the information, the 'tools' and the principles behind them, they can adapt these to their local situation and start solving their own problems.

Root crops
In root crops in Africa, research and training are looking to integrate genetical and biological control. Sweet potato varieties are under assessment for resistance to two species of sweet potato weevil, whilst a fungal disease, Beauveria bassiana, is intended to further reduce weevil populations. In Burundi and Kenya technicians are learning laboratory and field trial techniques for applying the fungal spores to the soil in an oil-based formulation, with the aim of developing a low-technology procedure suitable for farmers, using locally available materials.

Mango
Mechanical control methods, although labour-intensive, can do away with much harmful pesticide spraying. Through on-farm research and demonstration we have developed an IPM strategy with mango growers in the Punjab which has cut the number of annual sprays from five to one, at a 14-fold reduction in cost. Farmers now hoe around the base of trees in winter to expose and kill mealybug eggs laid in the soil, and they provide over-wintering refuges for predatory ladybirds on the smooth trunks of the mango trees by fastening bands of rough sacking to mimic bark crevices. To avoid spraying against fruit flies, traps are made from local materials and baited with an imported fruit fly attractant. Mango hopper is still a problem which requires spraying, but studying the distribution of this pest showed only the lower part of the trees need to be sprayed, saving money and effort. Carrying out ecological research with growers enables them to understand the rationale behind the control techniques and to experiment themselves.

Coffee
Our new coffee programme in Latin America will also involve growers closely in the process of IPM development, trying out techniques on-farm which can link in with farmers’ practices, rather than generating unadoptable recommendations from the isolation of a research station. The commitment of the Colombian Coffee Growers’ Federation, CENICAFE, with whom we are working, to phase out endosulfan application in their estates, gives members the motivation to look for new solutions for controlling the coffee berry borer. Populations of this beetle have been lowered by the introduction of two parasitic wasps from its native Africa and the project will look to combine these natural enemies with a biopesticide of the Beauveria fungus. The Colombian farmers and outreach staff will become experts in wasp rearing and the use of fungal pathogens by the end of the programme.

Cotton
Perhaps the biggest challenge for IPM lies in cotton. More pesticides are sprayed on this crop than any other and they have brought a trail of farmworker poisonings, drinking water contamination, and secondary pest outbreaks in subsistence crops in their wake. It is possible to produce good yields with greatly reduced pesticide application, yet IPM strategies have not been taken up by farmers. IIBC’s latest programme is to help make IPM a reality in cotton in China, India and Pakistan. We will use the Asian rice IPM work as a model, training farmers to understand what is going on in their fields and to make the break with insurance spraying and give natural enemies and cultural methods a chance. Extension staff will become IPM Trainers and Pest Observers and co-ordinate Cotton Farmer Field Schools. Comparison plots in farmers’ fields have been set up to show the difference between not spraying at all; following IPM recommendations; and current chemical practices.

Sharing biocontrol with a wider audience
Some of the most exciting work in sustainable agriculture, in countries of both the North and South, is being carried out not by academics or ministries but by a host of non-governmental organisations consisting of aid agencies, community self-help groups, and environmental associations. Local rural development projects are springing up, integrating health, farming, income-generation and natural resource conservation. Farmers are encouraged to practise soil conservation, experiment with local crop varieties, produce compost, and make their own pesticides from ingredients such as chilli, garlic, neem tree seed and soap. So far nobody has talked much about natural enemies and how farmers can take advantage of this free pest control.
    By liaising with like-minded NGOs in Britain and abroad, we hope to raise awareness among agriculturalists and environmentalists and the farmers they work with, about the benefits of biocontrol and how they can make it work for them. Our training manual in preparation forms a stepping stone to closer collaboration, and NGO field workers will be reviewing draft versions to help us get the level right. We would also like to encourage people working in sustainable agriculture programmes to come on our four week biocontrol training course in the UK in May.

Off the treadmill
One of the areas of great concern to many people working in development issues is the rapid growth of the export horticulture business in tropical countries. Faced with a demand for cosmetically perfect fruit, vegetables and flowers in Northern markets, producers are tempted to step onto the pesticide treadmill, especially since they are often growing crops new to their area and highly susceptible to pests, both native and foreign. Many of these producers are small and medium scale farmers working with little technical support from the state. At the same time, political pressure to reduce pesticide residues in imports means that shipments are sometimes rejected at Customs in importing countries. IIBC is carrying out a survey of export growers to find out their views on pest problems, control solutions, and what kind of information and support would be most useful for them.

For more information contact:
Training & Information Officer, IIBC, Silwood Park, Buckhurst Road, Ascot, Berks, SL5 7TA, Tel: 0344 87299.
IIBC’s 4 week 'hands-on' course in Biological Control of Arthropod Pests and Weeds will take place from 3-27 May 1994 at Silwood Park.
Stephanie Williamson now works at Pesticide Action Network UK. 

[This article first appeared in Pesticides News No. 23, March 1994, pages 7-9]