Increased resistance to a generalist herbivore in a salinity-stressed non-halophytic plant

During their life, plants face multiple stresses. However, studies on single stress factors have typically neglected possible interactions with other factors. In a recent study published in AoB PLANTS, Renault et al. demonstrated that salt stress in Indian mustard (a plant species not adapted to salinity) lessens the effect of herbivory on plant mass, and increases the plants’ constitutive resistance to herbivores. Changes in the plants associated with increased salt that help to explain the mitigation of herbivore effects include decreased protein and macronutrient content. Plants exposed to herbivore damage were also less negatively affected by salt exposure, possibly due to their ability to maintain higher levels of transpiration.