Early Molecular Responses of Tomato to Combined Moderate Water Stress and Tomato Red Spider Mite Tetranychus evansi Attack

Abstract

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.

Research Progress on Plant Responses to Stress Combinations in the Context of Climate Change

“…Amid climate change and heightened environmental intricacies, the intersection of abiotic and biotic stresses has become a key research focus. Numerous studies investigating combined stresses delve into the interplay between abiotic and biotic stressors, like the interactions between drought and pests, cadmium and pathogens, and drought and pathogens [ 31 , 32 , 33 , 34 ]. Reports are available indicating that certain abiotic stress conditions, such as ozone stress, can bolster plant resilience against pathogen attacks in certain cases.…”

“…Reports are available indicating that certain abiotic stress conditions, such as ozone stress, can bolster plant resilience against pathogen attacks in certain cases. However, in most scenarios, prolonged exposure of plants to abiotic stresses, such as drought or nutrient deprivation, tends to weaken their defenses, making them more susceptible to pests or pathogens, such as arthropods [ 11 , 33 , 35 ]. Abiotic stresses play a pivotal role in modulating plant tolerance or susceptibility to pathogens through various mechanisms, resulting in altered plant–pathogen interactions, influenced by factors such as plant species, pathogen type, and stress intensity [ 23 ].…”

Nitric Oxide in Plant Functioning: Metabolism, Signaling, and Responses to Infestation with Ecdysozoa Parasites

“…The literature on NO-dependent responses of plants infested with arachnids is extremely limited [175,244]. In plants infested with arachnids, the involvement of ROS metabolism [245][246][247], antioxidant enzymes [246,248], phytohormone interactions [249,250], and transcriptomic [251,252] and proteomic changes [253] have been studied. Nevertheless, despite the proven strong links between NO and the response to biotic stresses, there is no direct evidence in the literature.…”

Abscisic Acid as an Emerging Modulator of the Responses of Plants to Low Oxygen Conditions

“…To this respect, ABA has long been acknowledged as the main regulator of plant responses to abiotic constraints such as drought, salinity, high temperature stress, etc. Moreover, emerging roles for ABA as a regulator of complex plant responses such as the combination of abiotic-biotic stresses have been reported ( Ximénez-Embún et al, 2018 ; Arbona et al, 2020 ). However, its exact role on plant responses to low oxygen conditions, including abiotic factors that induce hypoxic or anoxic conditions to plant roots, has been partially over shaded by ET and other plant regulators.…”