Being an exotic crop, maize in Africa is not only prone to attacks by indigenous but also invasive pests species, introduced from other regions in the tropical world. Presently, the most devastating insect pests in East and Southern Africa are the invasive spotted stemborer (Chilo partellus) from Asia and the exotic storage beetle, the larger grain borer (LGB) (Prostephanus truncatus) from Meso-America, in addition to the indigenous maize stalk-borer Busseola fusca. While in the field stemborers cause yield losses of 20-40%, LGB attacks incur additional losses of stored grain of 30-90%.
icipe has been developing self-sustainable control options to reduce losses due to these pests focussing on biological control (BC). Some of them showed great success in the field and store. For example, the forecasted 20-year economic benefits of BC of C. partellus in Kenya alone are around $ 183 million. The project proposed here is to bridge icipe’s BC of maize pests program between two funding cycles. The previous phase of the stemborer project, funded by the Government of The Netherlands, came to an end in December 2006. Proposals have been submitted for continuation of biological control (BC) activities, which includes in addition to stem- and LGB several invasive species in East and Southern Africa. Though the chances of getting new funds are high, past experience showed that it could take a considerable time before funds become available. Thus, there is a risk that specialised staff at icipe and the national research institutions may be lost to the project and/or transferred to other programs.
The intended outputs of the project are: a) Finalizing a region-wide impact assessment of BC of stemborers; this will entail analyses of existing data and data to be collected in five countries. b) Mass-rearing and releases of Telenomus isis, parasitoid of B. fusca eggs; existing lab colonies will be boosted and releases and follow-up studies will be done in six countries in collaboration with national programs. c) Identification, introduction, mass-rearing and releases of available and new races of Teretrius nigrescens, a predatory beetle of LGB from Meso-America and Mexico; the work in the Americas will be done in collaboration with CIMMYT and national programs; available races will be mass-reared and immediately released in Kenya while new races will be released after assessment of their climatic requirements and predatory potential.
