Exogenous application of plant defense hormones alters the effects of live soils on plant performance

The overall effect of a live soil inoculum collected from nature on plant biomass is often negative. One hypothesis to explain this phenomenon that the net pathogenic microbial communities reduces performance. Induced defenses triggered by application hormones jasmonic acid (JA) and salicylic (SA) may help mitigate soil. However, little known about how such hormonal affects this, in turn, impacts growth. We grew four species sterilized inoculated exposed their leaves two treatments (JA SA). Two (Jacobaea vulgaris Cirsium vulgare) were negatively affected inoculation. In these foliar SA increased but not other (Trifolium repens Daucus carota) for reduced both Application JA soils all species. subsequently carried out multiple generation experiment one species, J. vulgaris. each generation, was mixture 10% previous 90% same applied. negative effects similar generations, mitigated SA. Our research suggests can Although containing natural community had strong growth vulgaris, we found no evidence an increase or decrease plant-soil feedback either control treated plants. Also performance did consistently with succeeding generations.