More than trichomes and acylsugars: the role of jasmonic acid as mediator of aphid resistance in tomato

ABSTRACT This study investigates the impact of priming on the resistance of tomato plants to the potato aphid Macrosiphum euphorbiae, focusing on the role of glandular trichomes. Glandular trichomes are specific hairs that provide protection to tomato plants against herbivorous insects. The experimental priming conducted in this study revealed that prior infestation by Spodoptera littoralis caterpillars increased the plant's resistance against M. euphorbiae, pointing at the jasmonic acid (JA) signaling pathway in regulating this plant-aphid interaction. Glandular trichomes type IV were effective against aphids regardless of the previous infestation. Using JA-deficient tomato (spr2), we observed that M. euphorbiae multiplication increased, while the number of aphids on salicylic -deficient NahG plants was lower than in the wildtype Moneymaker. These findings emphasize the crucial role of the JA signaling pathway in tomato plant resistance to aphids and the importance of glandular trichomes to enhance plant defences against pests.