Potential biocontrol agents for the blue couch grass, Digitaria abyssinica (A. Rich.) Stapf., in East Africa

Studies were carried out in 1992 - 1996 with the objective of identifying potential biocontrol agents for the weed Digitaria abyssinica . Seven muscid shoot-flies ( Atherigona spp.), four chloropid flies, two chrysomelid beetles, one pseudococcid bug and one rust fungus were found to be associated with the weed. Among these, Atherigona species were the most important control agents. Three of the Atherigona species attacked non-crop plants and caused up to 77% shoot damage to the weed. Atherigona were active throughout the year, but damage to the weed was more severe during the rainy season. Atherigona species were also strongly attracted to meat meal and when this material was applied, attack by the flies increased dramatically.

Keywords:

• Atherigona Spp.
• Biocontrol
• Digitaria Abyssinica
• East Africa