June 1999, Volume 20 No. 2

• Editorial
• General News
• Training News
• Internet Round-Up
• Announcements
• Conference Reports
• Biorational
• New Books

Training News

In this section we welcome all your experiences in working directly with the end-users of arthropod and microbial biocontrol agents or in educational activities on natural enemies aimed at students, farmers, extension staff or policymakers.

Kenyan Farmers Validate Traditional Methods

Farmer Field School (FFS) training has been conducted in Kenya since 1996 through a collaborative project of IPM staff at CABI Africa Regional Centre with the Kenya Agricultural Research Institute (KARI), the Coffee Research Foundation (CRF) of Kenya, the Ministry of Agriculture Livestock Development & Marketing (MOALD&M) and the Kenya Institute of Organic Farming (KIOF). The target cropping system is smallholder mixed cropping of coffee and vegetables (mainly kale, cabbage and tomato) in the central highlands. Many small-scale farmers in these areas have virtually abandoned their coffee bushes due to low coffee prices and the rise in pesticide costs. Those growing tomatoes for the local market spend an increasing proportion of their production costs on insecticides and fungicides.

FFS groups were set up in four agro-ecological zones with approximately 65 farmers in total including organic farmers and those using pesticides. Each group carried out weekly observations on small plots in the field to compare their usual cultivation and pest control practices with various IPM options. They also conducted experiments on alternative crop management methods, including traditional methods for insect pest and disease control. The tomato growers, in particular, discovered the benefit of preparing compost and using liquid manures and plant tonics to produce more robust plants. The organic groups learnt to look at the efficacy of botanical and other homemade extracts for pest and disease control and compared the usefulness of different methods for nursery bed soil preparation. FFS farmers in all groups were able to reduce production costs, improve yields and apply the IPM principles learnt to other crops in their farms. However, many questions came up on the effectiveness of traditional methods, and to address these CABI, KARI and KIOF facilitated innovative farmer participatory research methods in 1998 with two established FFS groups.

Organic farmers and an all-women tomato growers group conducted season-long research into traditional methods for pest and disease management according to their particular interests. These validation experiments quantified and assessed the effectiveness of the following methods:

• Nursery bed hygiene methods (trash-burning, hot water and incorporation of Mexican marigold) for control of rootknot nematode in tomato
• Marigold and chilli concoctions for control of aphid and caterpillars in kales
• Pegging (placement of a thin stick next to the seedling stalk so that cutworm cannot coil around and bite through stem) and ash for control of cutworms
• Foliar sprays of diluted milk to delay onset of blight in tomato

The farmers participated on an equal basis with researchers in trial design, management, data collection and evaluation. Farmers took the lead in teaching researchers the practical use of traditional methods while the scientists advised on trial lay-out, replication and assessment parameters. Farmers were already familiar with weekly field observations for AgroEcosystem Analysis through their FFS experience, where they study crop health, pests, diseases and beneficial insects and record these visually on posters for discussion. These analyses were modified to include macroscopic observations such as percentage germination, root-shoot length measurement, rootknot nematode galling index in tomato seedlings, and kale leaf quality scoring. Field observations were backed up by microscopic laboratory assessments such as nematode counts from soil samples and sampled seedlings. The farmers divided into three groups to organize observations and data collection via AgroEcosystem Analysis preparation and presentation. The group secretaries entered the data collected into structured record sheets. In the plenary, each secretary presented data, which was filled into a large flip chart. The facilitator encouraged discussions, which formed the basis for the next course of action. In the discussions, the researchers, farmers and extension staff participated in contributing ideas. In the nursery bed hygiene experiment, questions included:

• What are the differences in seedling establishment in each treatment?
• Which nursery is preferred and why?
• What should be done and by whom before the next meeting? (e.g. weeding, watering)
• Are there any specific materials or tools that need to be brought along in the next meeting? If yes, who will bring what?
• What went right today (facilitation, time keeping, learning)?
• What went wrong? How will this be corrected?

At the end of the session, scientists took back the record sheets with records to the office for statistical analysis while the facilitator copied the same in his/her field note book. The data on the large flip chart remained with the FFS group; thus the farmers developed their own learning materials and records.

Preliminary analysis of results showed that trash-burning was the most effective soil treatment in terms of overall seedling health, followed by dried marigold. In the experiment on botanical concoctions for aphid and diamondback moth (DBM) control in kales, Karate? (lambda-cyhalothrin) application produced the best quality leaves but there was no difference between the insecticide and highly concentrated chilli solution treatments in production of marketable leaves. The groups found that fresh marigold tea repels DBM larvae for a few hours only. Chilli sprays reduce pest numbers by 50% in the first week after application but these build up again so chilli needs to be sprayed every 14 days for effective control. In the cutworm experiment, no kale seedlings were lost in either the pegging or the ash treatments, compared to 5% loss due to cutworm damage in control plots. Farmers decided to use pegging as the favoured control option as it keeps cutworms available for natural enemies. In the tomato disease experiment, the fungicide treatments and control plots performed better than milk spray plots although some farmers want to repeat the experiment under dry season conditions when they claim milk can be effective.

Joint evaluation of the results has enabled the farmers to compare different traditional methods with synthetic pesticide treatments and no-intervention control plots in terms of cost, labour, efficacy, duration of effect, quality of produce and possible side-effects on beneficial insects. These comparisons help them to make better informed decisions on their crop management options. The research organizations involved have benefited by more direct links with farmers and are now expanding their research agenda to include on-farm experimentation on traditional methods, in close collaboration with farmer trainers from extension and KIOF. Further research will look in detail at the efficacy of chilli solutions for kale pest management and their effect on key syrphid natural enemies. The facilitators have gained useful experience and confidence in conducting simple but rigorous experiments to answer questions posed by farmers. Conducting research as an FFS group also provided material benefits to each member and strengthened group cohesion. Fresh produce from the kale sampling sessions was shared between participants and each member took home 200 seedlings from the nursery experiments to plant on individual plots. The remaining seedlings were sold to neighbours and the profits entered into the FFS group account. Farmer participatory research of this type reinforces IPM training programmes and stimulates the adaptation and implementation of IPM options which address the problems of smallholder farmers.

Contact: Martin Kimani, IPM Coordinator, CABI Africa Regional Centre, ICRAF Complex, PO Box 633, Village Market, Nairobi, Kenya
Email:
Fax: +254 2 522150

Augmenting Liriomyza Parasitoids

An ingenious method being developed by Indonesian plant protection staff to enable farmers to augment Liriomyza parasitoid populations was described at an international workshop held at Tanah Rata, Cameron Highlands, Malaysia in January 1999. The workshop was organized by the CABI South-East Asia Regional Centre (SEARC) and was held to collate information on the state of Liriomyza in South-east Asia and to identify national needs and criteria including inter-country linkages.

In western Sumatra, field laboratory staff survey areas of a farmer's crop (cauliflower, for example) that are attacked by Liriomyza but where pesticide usage has been low. A small number of old leaves are sampled, and the numbers of Liriomyza and parasitoids (principally Hemiptarsenus spp. and braconids) are compared. If parasitoids represent 75% or more of the total number, then the leaves are regarded as suitable for use as parasitoid carriers for augmentation release.

Farmers collect Liriomyza-attacked leaves from the area from which the samples were taken. These leaves are tied in bundles of five. Each bundle is hung on the tip of a 50-cm-long stick, which is pushed into the ground, with one stick for every 10-m area. Then - in a simple but clever step - a small depression is made around the stick. The Liriomyza larvae are first to emerge from the leaves, and they drop down to the ground to pupate. Five days after the stick was planted in the ground, the depression is filled in by heaping up earth, and the Liriomyza pupae are buried and die. The parasitoids emerge later: Hemiptarsenus pupates in the leaf gallery made by Liriomyza and the adult emerges by piercing the epidermis, but braconid larvae crawl out of the leaf, drop to the ground, and pupate on the fresh soil surface.

In some areas augmentation is conducted about every two weeks after planting, elsewhere, action is based on observation. However, the efficacy of this method has not yet been assessed, and the need to do this is beginning to be addressed by two- or three-weekly sampling and comparison of parasitoid and Liriomyza populations.

Contact: Mr Zamzami, Head of Field
Laboratory, Plant Protection Centre Region II, Jln. Raden Saleh 2, Padang,
West Sumatera, Indonesia
Email:
Fax: +62 751 55587