Tuta absoluta (Lepidoptera: Gelechiidae) ability to develop on potato tubers

Tuta absoluta (Lepidoptera: Gelechiidae) is a widespread pest that threatens commercial production of solanaceous crops. Larvae feed on the mesophyll of all aerial parts of the plants resulting in significant yield losses and cosmetic damages.It is classically assumed that underground plant parts are not affected but larval development on potato tubers has recently been suspected. However, this assumption is poorly supported in the literature. Potato tubers might represent an unsuspected mean of persistence and dispersal in agricultural environments.Oviposition tests were here conducted using dormant and active (sprouts less than 5 cm) potato tubers in net cages. Oviposition only occurred on the sprouts of active tubers, supporting larval growth until adult emergency. Tuber dissection revealed burrows starting from sprouts inside the flesh. Additional fitness assays were conducted on non-sprouted tubers and revealed that first instar larvae were able to enter the skin and create burrows, living inside and feeding on potato flesh, although none of them survived.