How does fertilization impact the wild blueberry microbiome

Abstract

Wild blueberries production is regarded as less intensive than other agricultural systems, although several agricultural practices are commonly implemented to increase crop yields and to mitigate pets and pathogen attacks. Fertilization, organic or mineral, 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 symbiosis with ericoid mycorrhizal fungi is thought to be crucial in that regard. 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 at the time of application and more than year later during the harvest season. 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 ericoid mycorrhizal (ErM) fungal community as no significant differences were observed in terms of relative abundance on known and putative ErM taxa between the control and the two fertilizer treatments. The fact that fertilization is applied at a low rate could explain this absence of effect on the microbial communities. However, longer-term studies are needed to ensure that repeated fertilization does not cause any shifts in microbial communities that could be detrimental to the wild blueberry nutrition. ImportanceThis study examines the impact of fertilization, whether organic or mineral, on microbial communities in the roots and rhizosphere of wild blueberry (Vaccinium angustifolium Ait.). both Fertilization is commonly used to enhance soil nutrient availability and improve fruit yield, but its effects on the plants microbiome, particularly on the ericoid mycorrhizal fungi (ErM), are not well understood. The samples were taken both during the pruning season, 3 months after the treatment, and one year later, during harvest season. The results suggest that fertilization has minimal impact on the microbial communities. One year after application, no significant differences were observed in the relative abundance of known and putative ErM taxa between the control group and the two fertilizer-treated groups. The low amount of fertilization applied could explain these results. However, longer-term research are needed to ensure that repeated fertilization does not lead to detrimental shifts in microbial communities affecting wild blueberry nutrition.