How does fertilization impact the wild blueberry microbiome?

Wild blueberries production is regarded as less intensive than other agricultural systems. Fertilization is used to increase soil nutrient availability and improve fruit yield. Wild blueberry plants are also known to depend on their microbiome to overcome the lack of nutrient availability in the soil and their ericoid mycorrhizal (ErM) symbiosis. As fertilization can alter crop microbial communities, our study aimed to measure the impact of this practice in a wild blueberry setting, focusing on the bacterial and fungal communities found in the roots and rhizosphere of Vaccinium angustifolium Ait., both three months and one year after fertilization. Our study indicates that fertilization, whether mineral or organic, has a minimal effect on microbial communities. One year after application, fertilization does not seem to have a negative repercussion on the ErM fungal community as no significant differences were observed in terms of relative abundance of known and putative ErM taxa between the control and the two fertilizer treatments. The fact that fertilization is applied at a low dose and once every other year could explain this absence of effect on the microbial communities. However, longer-term studies are still needed to ensure that repeated fertilization does not cause any detrimental shifts in microbial communities.