Plant–soil interactions in wheat and coriander crops driving arthropod assemblies through volatile compounds

Arthropod assemblies are frequently determined by bottom-up interactions that include emission of organic volatile compounds. Therefore, changes in soil characteristics associated with land use history can influence the volatile emissions of plants affecting the structure of arthropod assemblies in croplands. This study aims (1) to study the relationships between soil degradation levels due to land-use history, and the change in particular soil chemical characteristics; (2) to analyze plant–soil interactions quantifying the effect of soil degradation on the production of biomass and grain yield of coriander and wheat crops, and on the production and chemical composition of volatile secondary metabolites in coriander grain; (3) to find the relationship between the analyzed plant–soil interactions and the emission of volatile signals affecting arthropod assemblies; and (4) to determine the relationship between particular chemical soil characteristics and the structure of arthropod assemblies. For these purpose, two experiments were carried out in which volatile compounds were conducted from source plots with soils with different levels of degradation, sown with wheat or coriander, to sink plots with similar soil, sown with wheat. Crops were evaluated on source plots, and the arthropods communities were assessed on sink-plots. Coriander produced high biomass, grain yield and essential oil in the favorable environments and wheat produced higher biomass and grain yield in soil with low degradation than with high degradation. Particular chemical soil elements, for example, Na, Fe, Mn, N and CEC and essential oil components, for example, γ-trepanned, p-cymene, asinine and β-pinene could be involved in the arthropods assemblies. Based on these results, arthropods communities in agricultural systems are, at least, partially controlled by chemical signals, which depend on plant–soil interactions.