Farmers’ knowledge and perceptions of blister beetles, Hycleus spp. (Coleoptera: Meloidae), as pest herbivores of Desmodium legumes in western Kenya

Abstract

A survey was undertaken to determine the pest status of herbivorous blister beetles, Hycleus spp., in western Kenya where they attack crops such as Desmodium spp., other leguminous plants and sweetpotato. Desmodium spp. are important intercrops in the ‘push–pull” strategy adopted for Striga and stemborer control in maize and sorghum. Production of desmodium seed is adversely affected by blister beetles, which feed on the flowers and negatively affect seed setting. To assess farmers’ knowledge and perceptions of Hycleus spp. as pests, a questionnaire survey was conducted in three sites in Bungoma district, western Kenya, in 2007. The survey was followed by field sampling of Desmodium spp. and sweetpotato to compare the results with the responses received from farmers. Hycleus spp. were mentioned by 75% of the respondents as major pests of Desmodium spp. During field sampling Hycleus spp. comprised 70% of the insect pests collected. According to farmers, blister beetles were more abundant on desmodium than on sweetpotato. However, field sampling revealed that differences in beetle abundance on the two crops were not consistent across different sites, suggesting that these crops may function as alternative hosts. The study provides baseline information for the development of a management strategy for blister beetles.

Keywords:

• Desmodium spp
• questionnaire
• field survey
• pest status
• sweetpotato

Acknowledgements

Research funds for this study were provided by Gatsby Charitable Foundation (UK) and the Kilimo Trust (East Africa). DAAD, the German Academic Exchange Service, provided a grant to cover living expenses in Kenya for the first author. The University of Pretoria and the Lesotho Government are also acknowledged for providing both financial and logistical support in South Africa. We would like to express our gratitude to the following persons: Prof.Marco Bologna, Roma TRE University who identified the blister beetles free of charge; Mr J. Pitchaar and DrA.Amudavi for commenting on the design of the questionnaires; Dr E.M. Njuguna, and anonymous referees for critical evaluation of the manuscript; Dr C. Midega for his comments on an earlier version of this work; the icipe field staff based in Bungoma and Kitale, specifically Aloice Ndiege and Phillip Akelo, who provided logistical support.