Metabolic response to larval herbivory in three <i>Physalis</i> species

The <i>Physalis</i> genus includes species of commercial importance due to their ornamental, edible and medicinal properties. These qualities stem from their variety of biologically active compounds. We performed a metabolomic analysis of three <i>Physalis</i> species, i.e., <i>P. angulata, P. grisea</i>, and <i>P. philadelphica</i>, differing in domestication stage and cultivation practices, to determine the degree of inter-species metabolite variation and to test the hypothesis that these related species mount a common metabolomic response to foliar damage caused by <i>Trichoplusia ni</i> larvae. The results indicated that the metabolomic differences detected in the leaves of these species were species-specific and remained even after <i>T. ni</i> herbivory. They also show that each <i>Physalis</i> species displayed a unique response to insect herbivory. This study highlighted the metabolite variation present in <i>Physalis</i> spp. and the persistence of this variability when faced with biotic stressors. Furthermore, it sets an experimental precedent from which highly species-specific metabolites could be identified and subsequently used for plant breeding programs designed to increase insect resistance in <i>Physalis</i> and related plant species.