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Cx.S' V\P O R323 Mir ismir cx.s' v\P o r323 GiiNI FO LT-N ETAT 1/(t eve" 1/51 AG Fl IC 4 5 LTU RAI_ E.C 0 N 0 t.f. C-Fi: FIT,/ AGRICULTURAL ADMINISTRATION (RESEARCH AND EXTENSION) NETWORI NETWORK PAPER 42 ISSN 0952-2468 %mum. July 1993 ROLES FOR FARMERS' KNOWLEDGE IN AFRICA Two Papers by: C R Riches, L J Shamon, J W M Logan and D C Munthali and Simon Batterbury Charles Riches, Louise Shaxson and J W M Logan are weed scientist, agricultural economist and entomologist respectively at the Natural Resources Institute, and can be contacted at: Natural Resources Institute, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK D C Munthali is Director of the Soil Pests Project at the University of Malawi, and can be contacted at: Soil Pests Project, Chancellor College, University of Malawi, PO Box 280, Zomba, Malawi Simon Batterbury worked with Cellule Recherche-Developpement,PATECORE (GTZ), BP 271, Kongoussi, Barn, Burkina Faso. He can currently be contacted at: West London Institute of Higher Education, Geography Department, Gordon House, 300 St Margaret's Road, Twickenham, Middlesex TW1 1PT Network Personnel: Coordinator: Anthony Bebbington Assistant Coordinator: John Farrington Secretary: Alison Saxby This Network is sponsored by: The Overseas Development Administration (ODA) 94 Victoria Street, London SW1E 5JL The opinions expressed in this paper do not necessarily reflect those of ODA. Photocopies of all or part of this publication may be made providing that due acknowledgement is made. Requests for large-scale reproduction of network material should be directed to ODI as copyright holders. The Network Coordinator would appreciate receiving details of any use of this material in training, research or programme design, implementation or evaluation. CONTENTS Page 42a. Insect and Parasitic Weed Problems in Southern Malawi and the Use of Farmer Knowledge in the Design of Control Measures by C R Riches, L J Shaxson, J IV M Logan and D C Munthali ABSTRACT 1 INTRODUCTION 1 INTRODUCTION TO THE THREE PESTS 3 Striga asiatica: witchweed 3 Cylas puncticollis Boheman: the sweet potato weevil 4 Ophiomyia spp.: the beanfly 4 COLLECTING INFORMATION: HOW FARMER PERCEPTIONS OF PESTS CAN COMPLEMENT FIELD DATA 5 A FRAMEWORK FOR EXAMINING FARMER KNOWLEDGE 5 FARMER KNOWLEDGE OF PEST BIOLOGY AND ECOLOGY 7 Farmer knowledge of Striga biology 7 Farmer knowledge of the biology of the sweet potato weevil 11 Farmer knowledge of the biology of the beanfly 11 PLANNING A PROGRAMME OF ADAPTIVE RESEARCH: THE STRENGTHS AND WEAKNESSES OF INDIGENOUS TECHNICAL KNOWLEDGE 12 A programme for Striga control 12 Programmes for insect control 13 Page EMPOWERMENT THROUGH INFORMATION 14 REFERENCES 15 Figure 1. Four Classes of Farmer Knowledge 6 42b. Planners or Performers? Indigenous Dryland Farmers in Northern Burkina Faso by Simon Batterbury ABSTRACT 18 A BACKDROP TO INDIGENOUS AGRICULTURAL INNOVATION: 19 INSTITUTIONAL ACTIVITY IN THE CENTRAL PLATEAU THE CONSTRUCTION AND MANAGEMENT OF DRYLAND FARMING SYSTEMS 20 INDIVIDUALITY, DESIGN CHOICE AND LEARNING IN MOSSI COMMUNITIES 92 PLANNED PERFORMANCES AND FARMER STATUS 24 CONCLUSIONS - RECOGNISING MULTIPLE SOURCES OF CHANGE IN ITK 26 ' REFERENCES 29 INSECT AND PARASITIC WEED PROBLEMS IN SOUTHERN MALAWI AND THE USE OF FARMER KNOWLEDGE IN THE DESIGN OF CONTROL MEASURES' C R Riches, L J Shaxson, J W M Logan and D C Munthali ABSTRACT Researchers worked with a group of farmers in Southern Malawi to find out what farmers know about witchweed (Striga asiatica), the sweet potato weevil (Cylas puncticollis) and the beanfly (Ophiomyia spp.) and how this affects the ways in which a control programme could be implemented. Although some relationships between pest problems and other factors such as soil fertility were generally well recognised by the farming community, the farmers contacted by this project lacked some of the detailed biological and ecological knowledge that is necessary for an understanding of why, certain control practices are necessary. These gaps in their understanding have a direct bearing on farmers' current approaches to control. The authors conclude that providing farmers with this information is essential if the control technologies being developed are to be sustainable. INTRODUCTION There is an increasing awareness of the contribution of indigenous technical knowledge to agricultural research. Farmers' understanding of their environment and their agricultural practices have been documented since (for example) the colonial era in Africa (see Richards, 1985, chapter 1). However, its potential contribution was not brought into the mainstream of development thinking until The Soil Pests Project at the University of Malawi is funded by the Overseas Development Administration through the Natural Resources and Environment Departinent's support to the Integrated Pest Management programme at NRI. However, opinions expressed here do not necessarily reflect those of NRI, nor of ODA. The authors would like to thank Mr R L Satifula for his contribution to gathering information on farmer knowledge. 1 the rise of the "farmer first" movement that began with Richards, Rhoades and Chambers in the mid-1980s. Farmers may well, be more familiar with various aspects of the farming environment than the "experts" called in to assist them. Current literature is full of descriptions of farmers' intricate knowledge of different aspects of agricultural production. Farmers in Malawi intercrop in a multitude of patterns according to the particular micro-environment; growing "certain beans on old anthills, or certain crops cross-hatched with others, or in patches where the soil was of different quality" (Peters et a/., p.28). They have a detailed knowledge of the uses of indigenous plants for food and medicine (see Williamson, 1955, amongst others) and there is a growing number of reports of how farmers are continuously experimenting and improving their knowledge of the system in which they operate (see Chambers et al.). Chambers (1991) has observed that farmers know some things that scientists do not know while scientists know some things that farmers do not. To date, documentation of farmer knowledge has often been uncritical in that it tends to concentrate on aspects of agriculture about which farmers appear to know more than researchers. Less work has been done on what farmers do not know about particular problems. Bentley (1989) points out that "what farmers don't know can't help them": we must critically examine the gaps in knowledge of both farmers and scientists, to work out how they affect the development of sustainable agricultural technologies. This paper draws on the experience of the authors in working with the Soil Pests Project, based at Chancellor College at the University of Malawi. Three years of data collection, by both social and natural scientists, has given useful insights into how farmers' knowledge of the major pest problems can complement that of research scientists. However, we have found that for various reasons, farmers are unaware of some of the important biological and ecological features of the three key pests. These gaps in their understanding directly relate to the approaches they have used to date to control these pests. Witchweed, beanfly and the sweet potato weevil are all recognised by farmers in Southern Malawi to be major causes of yield loss. Witchweed infestation is closely associated with population pressure. Farmers in affected areas have few resources to commit to crop production and protection. It is therefore imperative that the design of control measures for this and any other crop "pest" is based on a clear understanding of farmer constraints and their knowledge of the biology of the problem. Where innovative control measures are developed, parallel research should be carried out to determine the additional knowledge farmers will need to understand how these work. Our aim is to develop an adaptive research programme for pest control and to identify what farmers need to be taught if they are to appreciate the rationale of, and hence be likely to adopt, appropriate control measures. We believe that without this step, sustained adoption of extension recommendations is unlikely. INTRODUCTION TO THE THREE PESTS Striga asiatica: witchweed Parasitic weeds in the genera Alectra and Striga (Scrophulariaceae) are now widespread constraints to cereal and grain legume production in much of Africa. According to Mboob (1989), Striga species are distributed throughout 40% of the arable land in sub-Saharan regions. On the basis of an analysis of recent surveys and field trials in a number of countries Sauerborn (1991) concluded that "Striga represents, at this time, the largest single biological constraint for the food production in Africa". Due to the difficulty of preparing Striga-free plots for valid comparisons there are few reliable estimates of crop loss due to parasitic weeds although Parker (1991) concludes that Striga species can cause complete crop failure and that losses of 30-50% are common under heavy infestations, with losses averaging 5-15%. It is not unusual for farmers in southern Africa to abandon severely infested land or to adopt a different cropping pattern to overcome the problem (Riches et al., 1986). Increased severity of Striga is generally associated with continuous cropping which has replaced shifting cultivation systems as a consequence of population pressure in many regions where these parasites are endemic (Parker 1991). This is due in part to the association of Striga infestation with low fertility.
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