A new study highlights the potential of Acerophagus papayae, a parasitic wasp, as a biocontrol agent against the destructive papaya mealybug in East Africa. The mealybug, an invasive pest affecting over 133 economically significant crops, causes severe losses by sucking sap from fruits. It first appeared in Kenya’s Mombasa County in 2016 and threatens papaya production in counties like Meru, Murang’a, Kitui, Busia, and Baringo.
The study revealed that while some regions in East and Central Africa are suitable for both the pest and the biocontrol wasp, vast cropping areas favor the pest but not the wasp. This insight can guide decisions on where to deploy A. papayae as part of integrated pest management.
Ivan Rwomushana, a co-author, emphasized that environmental suitability alone doesn’t guarantee the survival of A. papayae. The wasp’s success depends on the population density of its host, the papaya mealybug, as it cannot survive without it. Low pest density may reduce the wasp’s effectiveness even in favorable conditions.
To combat the pest, the international organization CABI has intensified efforts in Kenya, deploying A. papayae in counties like Machakos, Makueni, Embu, Tharaka Nithi, and Baringo. These initiatives aim to protect smallholder farmers, safeguard food security, and minimize losses caused by the mealybug.