Tanzania IPM project 01: Extension of the project on Biological control of Cassava Green mite in Tanzania

Duration: 2 years (2004-2006)

Purpose: To conduct country-wide surveys to determine the persistence of the predatory mites and their impact on cassava green mite populations, climate matching studies to determine the appropriate locations for introducing exotic isolates of mite pathogen Neozygites tanajoa and conduct media days to promote and publicize the impact of cassava green mite biological control in Tanzania.

Background/description: Cassava green mite Mononychellus tanajoa (Bonder) is one of the most important pests of cassava, the main staple food crop in Tanzania. In 1998, the International Institute of Tropical Agriculture (IITA) in collaboration with National Biological Control Programme (NBCP) introduced the neotropical phytoseiid predatory mite Typhlodromalus aripo to control cassava green mite in Tanzania. Impact assessment surveys conducted 6 years later revealed successful establishment, persistence and spread of the predator in four agro-ecological zones including the Lake zone (Mara and Kagera regions), Western Zone (Kigoma region), Southern highlands Zone (Mbeya and Ruvuma regions) and Eastern Zone (Tanga, Coast and Morogoro regions). Cassava green mite mean densities declined to low levels in all regions where T. aripo was established, while the pest remained 5-10 folds higher in few areas where T. aripo poorly established. The latter areas include Mara, Mwanza and Shinyanga regions in Lake Zone and Mtwara region in Southern zone. In order to reduce cassava green mite mean population density and damage severity to tolerable levels, IITA, in collaboration with NBCP, have agreed on the use of a fungal pathogen Neozygites tanajoa n.s.p as a complementary alternative approach in controlling further the cassava green mite in the remaining spots of high infestation.

Agro-ecological zones and locations: Lake Zone (Mara, Mwanza and Shinyanga regions); Southern Zone (Mtwara region)

Expected outputs: Country-wide surveys to determine the persistence of the predatory mite and their impact on cassava green mite populations accomplished, climate matching studies to determine the appropriate locations for introduction of exotic isolates of the mite pathogen Neozygites tanajoa completed and media days to promote and publicize the impact of cassava green mite biological control in Tanzania conducted.

Potential impact and beneficiaries: Cassava growing farmers in project areas will be the primary beneficiaries of the results from release of biological control agents, fungal pathogen Neozygites tanajoa by harvesting more cassava tubers and fresh cassava leaves (kisamvu) through reduction of CGM mean population densities. In addition farmers will also get healthy and clean planting materials. Environmental safety will be enhanced through reduced pesticide application.

Partners: International Institute of Tropical Agriculture (IITA), National Biological Control Program (NBCP) in

Development Investors: IITA

Contact person/Principal Investigators: Beatrice Pallangyo biocontrol@africaonline.tz; Dr. Rachid Hanna, R.Hanna@cgiar.org