DISEASES OF COCA (ERYTHROXYLUM COCA) AND THE ROLE OF EXTENSIONISTS IN THE HUALLAGA VALLEY OF PERU
DISEASES OF COCA (ERYTHROXYLUM COCA) AND THE ROLE OF EXTENSIONISTS IN THE HUALLAGA VALLEY OF PERU U KRAUSS 1 and HC EVANS 2 1 Universidad Nacional Agraria de la Selva, Apdo. 156, Tingo Maria, Huanuco, Peru; 2 CABI Bioscience, Silwood Park, Buckhurst Road, Ascot, Berkshire SLS 7TA, UK Background and objectives The Huallaga Valley of Peru is the largest coca-producing region world-wide. Several national and international R&D programmes have the objective to discourage illicit coca production by diversification. Diseases are the most limiting factor in the production of any crop there. This poster presents the diagnostic features of the principal coca disorders, summarises what is know about them and interprets the knowledge in the context of the role of extensionists. Results and conclusions The major coca diseases are seca-seca, a wilt caused by Fusarium oxysporum f. sp. erythroxyli, rust (Bubakia erythroxylonis), witches' broom (presumed phytoplasm) and leafspot (Phomopsis erythroxylonis). Nutrient deficiencies are common because coca is often grown on marginal land with minimum input. Little research has been done on coca; no diagnostic aids have been developed and virtually no recommendation for control exist. The entire production system of each farm is assessed by extensionists who give advice on socio-economically sustainable diversification. This entails guaranteeing a continuous income which, initially, depends strongly on coca. The fundamental basis for impact in extension is the confidence of the farmer. The extensionist, thus, faces a dilemma when his inability to advise on coca disorders is interpreted as deliberate refusal to address production problems.