Cereal stemborer species complex and establishment of cotesia flavipes cameron in eastern uganda

Studies were conducted in two districts of eastern Uganda from 1997 to 1999 to introduce and monitor the establishment of an exotic parasitoid, Cotesia flavipes Cameron (Hymenoptera: Braconidae), for the control of the stemborer Chilo partellns (Swinhoe) (Lepidoptera: Pyralidae), and also to determine the stemborer species complex in maize and sorghum. The study confirmed the presence of four important stemborers, two pyralids Ch. parlellus and Eldana saccharina Walker and two noctuids, Busseola fusca Fuller and Sesamia calamistis Hampson. Chilo partellus was dominant, constituting 53-88% of stemborers found followed by B.fiisca at 8-37 %. The most abundant local parasitoid was the larval parasitoid Cotesia sesamiae (Cameron) (Hymenoptera: Braconidae). The pupal parasitoids Pediobius fiirvus Gahan (Hymenoptera: Eulophidae) and Dentichasmias bitsseolae Heinrich (Hymenoptera: Ichneumonidae) were also recorded. Parasitism of Co. sesamiae on Ch. pariellns ranged between 0 and 13.1 %. The introduced Co. flavipes was recovered from all sites in four consecutive seasons (between 1998 and 1999) causing parasitism of between 4 and 32.9 % on Ch. parlellus. Cotesia flavipes was also recovered from the indigenous stemborers B. fusca and S. calntnistis. This study indicates that Co. flavipes has established in eastern Uganda. © 2001 ICIPE.