Integrated Pest Management is the solution to mango-infesting flies in Kenya

Mango is an important food and cash crop as it plays an important role in rural and urban socio-economic development in Kenya and Africa as a whole. Although the volume of mango produced has increased over the years, from below 250,000 metric tons in 2003 to over 750,000 metric tons in 2012 according to USAID-KHCP report in 2015, the productivity of mango in Kenya is still below its potential which is estimated at 2.8 million metric tons.

This has been attributed to high postharvest losses. Other major constraints hindering productivity are insect pest infestation particularly; tephritid fruit flies as well as diseases such as anthracnose and powdery mildew. According to Dr. Sunday Ekesi and Dr. Rwomushana Ivan from icipe, fruit flies cause direct damage by reducing mango productivity and quality, thus reducing the market value of the mangoes, and subsequently lowering revenues to farmers. In addition, quarantine restrictions on fruit fly-infested produce limit exports to lucrative markets abroad. 

Many farmers in developing countries, including Kenya, mainly rely on synthetic chemical pesticides to control insect pests such as fruit flies. The use (and misuse) of chemical pesticides is, however, often associated with high health and environmental risks. Researchers advocate the use of Integrated Pest Management (IPM) as a more sustainable alternative to widespread use of chemical insecticides.

The IPM approach aims at selection and use of pest control actions that ensure favorable economic, ecological and sociological consequences. This is currently recommended for the management of fruit flies in Africa as it minimizes the dependence on the use of chemical pesticides.

In Africa, the International Centre of Insect Physiology and Ecology (icipe) has spearheaded development and implementation of IPM strategy for managing fruit flies on mango, under the African fruit fly program (AFFP). The fruit fly IPM-based approach uses a combination of interventions including male annihilation technique, use of bio pesticides, protein bait, parasitoids among others. These interventions complement each other rather than work as a stand-alone management strategy.

To facilitate this, icipe has partnered with a private sector company, Kenya Biologics Ltd to establishing a local food bait production facility for fruit fly management across Africa which should become available in the near future at relatively cheaper price than imported products for horticultural growers in the continent. icipe is also working in partnership with another private sector company Real IPM Ltd which has produced a range of bio pesticides used in the management of various crop pests.

An impact assessment study recently carried by researchers from icipe indicates that farmers are gradually adopting the IPM strategy as they have been able to realize its benefits which include improving mango income, reducing mango losses due to fruit fly infestation, and reducing expenditure on pesticides across various households.