Neoleucinodes elegantalis (Lepidoptera: Crambidae): an organism invisible to the defences of tomato fruits.

Insect-plant interactions involving species of the genus Solanum have been intensively studied, resulting in several articles on insect-plant interactions. However, the interactions between herbivores and the fruits of Solanum lycopersicum (tomato) are not well known. Neoleucinodes elegantalis is a borer that causes great yield losses in S. lycopersicum crops because of the direct damage that it causes to the fruits and the difficulty of controlling it. In the field, the outside of a tomato fruit infested with the larvae of N. elegantalis is visually similar to uninfested fruits. Even a minor injury by herbivores can elicit a defensive response. Due to the lack of studies on interactions between fruit borers and S. lycopersicum, our aim in this study was to determine the locations of S. lycopersicum fruit in which the N. elegantalis larvae prefer to feed. An evaluation of nutritional sources was done through histochemical and biochemical tests and the defensive response of the S. lycopersicum fruit to attack by N. elegantalis larvae was evaluated through the detection of protease inhibitors ( PIs) and lipoxygenase ( LOX) activity. Our results show that the columella region is preferred by the N. elegantalis larvae and that this region has a nutritional source. Furthermore, attack by N. elegantalis larvae in the columella does not induce a significant increase in lipoxygenase activity and PIs. Thus, our results provide a better understanding of the interaction between the larvae of N. elegantalis and S. lycopersicum fruits and a better understanding of the evolution of plant-herbivore interactions, with an emphasis on the choice of feeding location as a strategy to avoid plant defences. [ABSTRACT FROM AUTHOR]