Contribution of ectomycorrhizal fungi to biogeochemical processes during iron and calcium limitation

Abstract

The symbiotic ectomycorrhizal fungi mediate nutrient uptake to boreal forest trees. Fungi are known to produce low molecular mass organic acids (LMMOAs), which are important weathering agents. Through weathering Al, Si and Fe, as well as nutrients important for plant growth i.e. P, Ca, K, Mg, and Na are released from solid minerals. The impacts of biogeochemical weathering caused by microbial exudates have been discussed but there is still a lack of knowledge regarding the production of important ligands from boreal forest tree-ectomycorrhiza interactions, as well as the effect of this symbiosis on mineral dissolution and nutrient cycling in forest soils. Here we examine how mineral nutrient mobilization was affected by fungal exudates in a closed mineral column experiment with pine seedlings with and without symbiotic ectomycorrhizal fungi (Hebeloma crustuliniforme or Suillus variegatus) with biotite and oligoclase as the only source for iron and calcium, respectively. The experiment was conducted for 20 months. We monitored the solution chemistry continually through out the experiment. At harvest the mineral chemistry and morphology, as well as size and element composition of the plant tissue was determined. We conclude that both the investigated ectomycorrhiza species, especially H. crustuliniforme, had a significant impact on the production of LMMOAs, mobilization of important mineral nutrients for plant growth, accumulation of elements in the plant shoot and root tissue, the exchangeble pool of elements, and plant growth during nutrient deficiency

Published in

Geochimica et Cosmochimica Acta
2009, volume: 73, number: 13, pages: A546-A546

Conference

19th Annual VM Goldschmidt Conference

SLU Authors

• Rosling, Anna

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

• Finlay, Roger

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Environmental Sciences

Permanent link to this page (URI)

https://res.slu.se/id/publ/38957