Data from: Single, but not dual, attack by a biotrophic pathogen and sap-sucking insect affects the oak leaf metabolome

Plants interact with a multitude of microorganisms and insects, both
belowand above ground, which might influence plant metabolism. Despite
this, we lack knowledge of the impact of natural soil communities and
multiple aboveground attackers on the metabolic responses of plants, and
whether plant metabolic responses to single attack can predict responses
to dual attack. We used untargeted metabolic fingerprinting (gas
chromatographymass spectrometry, GC-MS) on leaves of the pedunculate oak,
Quercus robur, to assess the metabolic response to different soil
microbiomes and aboveground single and dual attack by oak powdery mildew
(Erysiphe alphitoides) and the common oak aphid (Tuberculatus annulatus).
Distinct soil microbiomes were not associated with differences in the
metabolic profile of oak seedling leaves. Single attacks by aphids or
mildew had pronounced but different effects on the oak leaf metabolome,
but we detected no difference between the metabolomes of healthy seedlings
and seedlings attacked by both aphids and powdery mildew. Our findings
show that aboveground attackers can have species-specific and non-additive
effects on the leaf metabolome of oak. The lack of a metabolic signature
detected by GC-MS upon dual attack might suggest the existence of a
potential negative feedback, and highlights the importance of considering
the impacts of multiple attackers to gain mechanistic insights into the
ecology and evolution of species interactions and the structure of
plant-associated communities, as well as for the development of
sustainable strategies to control agricultural pests and diseases and
plant breeding.