Studying chemical signals in plant–soil mesofauna interactions

Abstract

Discrimination of compounds produced from plant roots is a challenging purpose, especially in presence of the soil matrix and the associated fauna. In this study, we aimed to test a collection method of chemical signals released by living plants and soil fauna in interaction in a soil matrix. Microcosms, with stopcock, were filled with soil, and four treatments were designed based on the presence/absence of an annual herbaceous plant, Poa annua and of a soil Collembola species, Folsomia candida. Soil leachates were collected with a percolated solution and analyzed by a fast analytical method combining analytical separation of compounds through ultra high performance liquid chromatography with high resolution mass spectrometry (UHPLC-HRMS). The experimental design appears to be suitable for leachates sampling. Detected chemicals clearly discriminated the treatments, demonstrating how biotic interactions belowground between a plant and a Collembola species may change soil chemical signals.