Beyond biomass: soil feedbacks are transient over plant life-stages and alter fitness

1. Plants influence associated soil biotic communities that in turn can alter the performance of the subsequently growing plants. Although such ‘plant-soil feedbacks’ (PSFs) are considered as important drivers of plant community assembly, past PSF studies have mainly addressed plant biomass production. However, plant performance is not only the production of biomass, but comprises a sequence of different life-stages: from seed germination over vegetative growth up to the production of a viable progeny.
2. Here we assessed the effects of soil biotic communities that were previously conditioned for three years by a focal plant species monoculture or species mixtures on key plant life-stages from germination and vegetative growth to flowering and the production of viable seeds. We used three common grassland herb species that were grown in a sterile substrate and inoculated with a sterile control soil, or with living soils. Living soils were conditioned either by the focal species in mono...