A project being implemented by the University of the Philippines Los Baños (UPLB) on the use of ribonucleic acid interference (RNAi) to control sweetpotato weevils has successfully identified a gene responsible for the development of the insect’s exoskeleton, or hard outer shell. Through this knowledge, researchers can target this specific gene to weaken the pest and make it easier to control.
RNAi is a process that silences specific genes, which prevents them from producing proteins. By targeting and disabling key genes, it can disrupt vital functions in insect pests such as growth, reproduction, or survival, making it a promising tool for pest control.
Meanwhile, sweetpotato weevil, a major pest in root crop production, can cause up to 100% yield loss, severely impacting food security and farmer livelihoods. Its larvae damage plants by burrowing into tubers and feeding on them, while adult weevils worsen infestations by laying eggs in the upper parts of the plant. This infestation also increases the risk of fungal infections.
To help address this problem, the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development of the Department of Science and Technology (DOST-PCAARRD) funded the project, “Exploring the Efficacy of RNA Interference (RNAi) as a Biopesticide for Managing Sweetpotato Weevil, Cylas formicarius (Fabr.).”
Led by Dr. Karen B. Alviar from the Institute of Weed Science, Entomology, and Plant Pathology of the College of Agriculture and Food Science of UPLB (IWEP-CAFS, UPLB), the research team successfully isolated and cloned a gene vital for forming the insect’s shell, mass-produced it in larger volumes using a medium with ampicillin, and stored it in a glycerol solution at low temperature.
The team also reported their developed protocol for the mass rearing of sweetpotato weevil, enabling a more efficient conduct of experiments.
Further studies will be carried out to develop an RNAi-based product that farmers can use to help control sweetpotato weevils in the field.
These accomplishments were shared during a project review led by DOST-PCAARRD Deputy Executive Director for Research and Development Juanito T. Batalon and Crops Research Division (CRD) Director Leilani D. Pelegrina, with the Council’s Industry Strategic S&T Program (ISP) Manager for Sweetpotato Fredric M. Odejar and other staff.