Abubakar Mshora, Marco Mng'ong'o, Luisa Santos, Tomás Chiconela
Tuta absoluta is an invasive species that has managed to expand beyond its native geographical area and causes severe yield losses in tomato. Despite the application of synthetic insecticides in getting rid of the pest, farmers have reported reduced efficacy over the course of time due to resistance. With regard to ecological pest management approaches, studies regarding the use of companion plants in the management of T. absoluta are scarce. Therefore, we screened fourteen potential companion plants for repellency using a Y-tube olfactometer followed by cage and screenhouse experiments. Data were analyzed using R software (version 4.6.0; R Core Team, 2026). The screening results showed that Allium schoenoprasum and Aeollanthus fruticosus significantly repelled T. absoluta compared to other potential companion plants at p < 0.001. In a dual-choice cage experiment, tomato plants placed with A. schoenopraum and A. fruticosus were recorded to have lower leaf damage percentages of 47.27% and 33.94%, respectively, compared to the negative control (66.34%). Similarly, tomato plants intercropped with A. schoenopraum and A. fruticosus showed lower leaf damage percentages of 13.92% and 25.00%, respectively, compared to the negative control (63.38%) under the screenhouse experiment. Therefore, A. schoenopraum and A. fruticosus exhibit significant potential in the management of T. absoluta in tomato.