Plant growth drives soil nitrogen cycling and {N}-related microbial activity through changing root traits

Relationships between plants and nitrogen-related microbes may vary with plant growth. We investigated these dynamic relationships over three months by analyzing plant functional traits (PFT), arbuscular mycorrhizal fungal (AMF) colonization, potential N mineralization (PNM), potential nitrification (PNA) and denitrification activities (PDA) in Dactylis glomerata cultures. D. glomerata recruited AMF during early growth, and thereafter maintained a constant root colonization intensity. This may have permitted high enough plant nutrient acquisition over the three months as to offset reduced soil inorganic N. PFT changed with plant age and declining soil fertility, resulting in higher allocation to root biomass and higher root C:N ratio. Additional to root AMF presence, PFT changes may have favored denitrification over mineralization through changes in soil properties, particularly increasing the quality of the labile carbon soil fraction. Other PFT changes, such as N uptake, modified the plants’ ability to compete with bacterial groups involved in N cycling.

Références

Title
Plant growth drives soil nitrogen cycling and {N}-related microbial activity through changing root traits
Publication Type
Journal Article
Year of Publication
2020
Journal
Fungal Ecology
Volume
44
Pagination
100910
Date Published
apr
ISSN
1754-5048
Keywords
CNRS, Lautaret
Submitted on 21 October 2021