Towards a collaborative research: A case study on linking science to farmers' perceptions and knowledge on Arabica coffee pests and diseases and its management

The scientific community has recognized the importance of integrating farmer's perceptions and knowledge (FPK) for the development of sustainable pest and disease management strategies. However, the knowledge gap between indigenous and scientific knowledge still contributes to misidentification of plant health constraints and poor adoption of management solutions. This is particularly the case in the context of smallholder farming in developing countries. In this paper, we present a case study on coffee production in Uganda, a sector depending mostly on smallholder farming facing a simultaneous and increasing number of socio-ecological pressures. The objectives of this study were (i) to examine and relate FPK on Arabica Coffee Pests and Diseases (CPaD) to altitude and the vegetation structure of the production systems; (ii) to contrast results with perceptions from experts and (iii) to compare results with field observations, in order to identify constraints for improving the information flow between scientists and farmers. Data were acquired by means of interviews and workshops. One hundred and fifty farmer households managing coffee either at sun exposure, under shade trees or inter-cropped with bananas and spread across an altitudinal gradient were selected. Field sampling of the two most important CPaD was conducted on a subset of 34 plots. The study revealed the following findings: (i) Perceptions on CPaD with respect to their distribution across altitudes and perceived impact are partially concordant among farmers, experts and field observations (ii) There are discrepancies among farmers and experts regarding management practices and the development of CPaD issues of the previous years. (iii) Field observations comparing CPaD in different altitudes and production systems indicate ambiguity of the role of shade trees. According to the locality-specific variability in CPaD pressure as well as in FPK, the importance of developing spatially variable and relevant CPaD control practices is proposed. (Résumé d'auteur

Biological control of the millet head miner Heliocheilus albipunctella in the Sahelian region by augmentative releases of the parasitoid wasp Habrobracon hebetor: effectiveness and farmers’ perceptions

On-farm augmentative releases of the parasitoid Habrobracon hebetor (Say) for controlling the millet head miner (MHM) Heliocheilus albipunctella (de Joannis) were tested in Burkina Faso, Mali and Niger from 2007 to 2009. In addition, a survey of farmers’ perceptions of insect pests, with particular focus on MHM, and the biological control program (BCP) was carried out. There was a significant increase of MHM parasitization rate after the releases, with up to 97% mortality. The survey on farmers’ perceptions revealed a fair knowledge of the MHM and the ability of farmers to describe the pest and the damage it caused. Farmers claimed that the biocontrol agent H. hebetor is effective and perceived a significant gain in grain yield due to this control strategy. Implications of these findings for a large extension of the MHM biocontrol program are discussed

Dynamique spatio-temporelle des populations d\'Altises Podagrica spp. (Coleoptera : Chrysomelidae) : implications agronomiques en zones cotonnières de Côte d\'Ivoire.

Quelques aspects écologiques de la dynamique spatio-temporelle des populations d\'Altises Podagrica spp. ont été étudiés dans les zones cotonnières de la Côte d\'Ivoire, en suivant l\'évolution des effectifs et des dégâts sur deux types de variétés de cotonniers (cotonnier glandless et cotonnier classique) et sur deux plantes hôtes (le gombo et le jute). Il ressort de ce travail que selon les localités, 3 à 6 générations se chevauchent durant la campagne agricole. Les fluctuations et les niveaux des infestations dépendent des facteurs climatologiques (pluviométrie, humidité relative, ETP, température), de la date de semis, de la taille et la localisation de la parcelle ainsi que de la disponibilité des plantes-hôtes. Sur la base de ces résultats, des méthodes culturales de lutte appropriées contre les Altises ont été recommandées : culture des variétés glandless sur de grandes superficies, exclusivement au nord du 9e parallèle et destruction des cotonniers après la récolte ainsi que les plantes-hôtesSome ecological parameters of the population dynamics of the flea beetles Podagrica spp. were studied in the cotton growing area of Côte d\'Ivoire. Population densities and damaged plants were scouted on two cotton varieties (glanded and glandless cotton) and two host plants (okra and jute). Data revealed, according to localities, that 3-6 overlapping generations of flea beetles occurred during the cotton growing season. Fluctuations and infestation levels depended on climatic factors (rainfall, relative humidity, ETP, temperature), cotton sowing dates, size and location of cotton fields, as well as on the presence of host plants. Based on these results, appropriate cultural methods to control flea beetles are recommended : cultivation of glandless cotton on large plots exclusively in the northern region above the 9th parallel, destruction of cotton plants after harvest and the host plants. Keywords: Cotonnier glandless, Altise, dynamique des populations, lutte culturale, Côte d\'Ivoire.Agronomie Africaine Vol. 18 (1) 2006: pp. 41-5