The Greater or Larger Grain Borer, Prostephanus truncatus has, in the last decade developed into one of the most threatening storage pests on the African continent, especially in the case of maize. The damage caused by the insect could reach the extent of jeopardizing many countries' self-sufficiency in this important crop. Whereas it is not such a menace in its original region of Central America, it has spread through at least ten sub-Saharan African nations since its introduction to the continent and is giving the Crop Protection Services in those countries a difficult task of controlling it.
Although a successful control can very possibly be achieved against the pest, it would require the implementation of appropriate and improved control measures and especially a change in the traditional storage methods. Anyone who is familiar with the situation in the small-scale farming sector knows that it is very difficult for the farmers to change storage practices that have partly been in use for centuries. Therefore, the national extension services of the Ministries of Agriculture in the various countries are playing a central role in the propagation of improved methods and their successful implementation on farmers' level.
After the accidental introduction of the insect into Kenya in 1983, the Republic of Kenya, through the Ministry of Agriculture and the Federal Republic of Germany, represented by the Deutsche Gesellschaft fuer technische Zusammenarbeit (German Agency for Technical Co-operation) GTZ decided to launch a joint project, "Control of the Greater Grain Borer" (GGB Project). The main objective of the project's activities, aside from the direct control of the pest, was to be the propagation of improved storage methods to the small-scale farming sector. This meant the working out of new training contents for the extension service as well as for various groups involved in handling of maize and in its inspection and also for decision-makers at the national and local levels.
After the GGB Project developed a national control strategy and after its approval by the Ministry of Agriculture, this manual was written, based on that strategy so that, in future, it will be utilized in the training of extension officers, farmers and other groups. The final goal of this manual is to offer alternative storage and control methods which can be applied independently and successfully by the farmers, traders, etc. Since the target group is relatively large, and its previous knowledge in the post-harvest sector is quite diverse, compromises had to be reached in the compilation - especially in the theoretical part (for example biological control) - in order to keep the statements as generally understandable as possible.
The manual is currently comprised of fourteen sections which, according to the prevailing level of knowledge, cover all possible relevant control strategies against the Greater Grain Borer under the Kenyan requirements. Since, in future, certain alterations (such as newly approved insecticides) and fresh scientific findings are inevitable, the manual was compiled in such a form as to allow each section to be easily replaced or new ones inserted. In this way, the manual presents an open system to which changes can be made at any time without involving high production costs. Each section - with the exception of the first one - has at least one hand-out which covers the most important points of the individual section and which should be distributed to the group being trained.
Concerning the extension service, this manual should be made use of in a cascade form, i.e. after the training of the Subject Matter Specialists by the Crop Post-Harvest Management Branch in the different districts infested with or threatened by the, GGB, the Technical Assistants and farmers should then be trained by the upper, already-trained levels. Special note - on technical training grounds - should be paid to the most complete use possible of the training materials listed in each section, the carrying out of the named practical components and the active involvement of each target group in the training session.
J. P. Mbandi
Director of Agriculture
