Interaction between plants and their environment is changing as a consequence of the climate
change and global warming, increasing the performance and dispersal of some pest species which
become invasive species. Tetranychus evansi also known as the tomato red spider mite, is an invasive
species which has been reported to increase its performance when feeding in the tomato cultivar
Moneymaker (MM) under water deficit conditions. In order to clarify the underlying molecular
events involved, we examined early plant molecular changes occurring on MM during T. evansi
infestation alone or in combination with moderate drought stress. Hormonal profiling of MM plants
showed an increase in abscisic acid (ABA) levels in drought-stressed plants while salicylic acid
(SA) levels were higher in drought-stressed plants infested with T. evansi, indicating that SA is
involved in the regulation of plant responses to this stress combination. Changes in the expression of
ABA-dependent DREB2, NCED1, and RAB18 genes confirmed the presence of drought-dependent
molecular responses in tomato plants and indicated that these responses could be modulated by
the tomato red spider mite. Tomato metabolic profiling identified 42 differentially altered compounds
produced by T. evansi attack, moderate drought stress, and/or their combination, reinforcing the idea
of putative manipulation of tomato plant responses by tomato red spider mite. Altogether, these
results indicate that the tomato red spider mite acts modulating plant responses to moderate drought
stress by interfering with the ABA and SA hormonal responses, providing new insights into the early
events occurring on plant biotic and abiotic stress interaction