Arbuscular mycorrhiza and nitrogen: Implications for individual plants through to ecosystems

TY - JOUR

T1 - Arbuscular mycorrhiza and nitrogen

T2 - Implications for individual plants through to ecosystems

AU - Hodge, Angela

AU - Storer, Kate

PY - 2015/1

Y1 - 2015/1

N2 - Background: Arbuscular mycorrhizal fungi (AMF) form mutualistic symbioses with c. two-thirds of all land plants. Traditionally, it was thought that they played no role in nitrogen (N) acquisition for their host, despite early evidence to the contrary. More recently, this perception has changed radically, with the demonstration that AMF can acquire N from both inorganic and organic N sources and transfer some of this N to their host plant.Scope: This review discusses the current evidence for AMF N uptake, transport and plant transfer under different experimental conditions and highlights key questions that remain to be resolved. The relevance of this AMF N acquisition pathway is discussed both in relation to host plant and fungal N nutrition. The importance of interactions with the soil community and subsequent implications for soil N cycling are also highlighted.Conclusions: Reported AMF contribution to plant N varies widely, but the reasons for this variability are unclear. In low N systems even small amounts of ‘extra’ N may confer the plant with a competitive advantage, but it is also likely that competition for N between symbionts occurs. To advance this area, a more mechanistic approach is required that treats the fungus as a Darwinian organism rather than a mere extension of the plant. Application of genomics and metabolomics technologies to this topic should enable resolution of some of the key questions outlined in this review.

AB - Background: Arbuscular mycorrhizal fungi (AMF) form mutualistic symbioses with c. two-thirds of all land plants. Traditionally, it was thought that they played no role in nitrogen (N) acquisition for their host, despite early evidence to the contrary. More recently, this perception has changed radically, with the demonstration that AMF can acquire N from both inorganic and organic N sources and transfer some of this N to their host plant.Scope: This review discusses the current evidence for AMF N uptake, transport and plant transfer under different experimental conditions and highlights key questions that remain to be resolved. The relevance of this AMF N acquisition pathway is discussed both in relation to host plant and fungal N nutrition. The importance of interactions with the soil community and subsequent implications for soil N cycling are also highlighted.Conclusions: Reported AMF contribution to plant N varies widely, but the reasons for this variability are unclear. In low N systems even small amounts of ‘extra’ N may confer the plant with a competitive advantage, but it is also likely that competition for N between symbionts occurs. To advance this area, a more mechanistic approach is required that treats the fungus as a Darwinian organism rather than a mere extension of the plant. Application of genomics and metabolomics technologies to this topic should enable resolution of some of the key questions outlined in this review.

KW - Arbuscular mycorrhizal fungi (AMF)

KW - Carbon (C)

KW - Nitrogen (N)

KW - Nutrient cycling

KW - Soil prokaryotes

KW - Sustainable agriculture

UR - http://www.scopus.com/inward/record.url?scp=84919844599&partnerID=8YFLogxK

U2 - 10.1007/s11104-014-2162-1

DO - 10.1007/s11104-014-2162-1

M3 - Article

AN - SCOPUS:84919844599

SN - 0032-079X

VL - 386

SP - 1

EP - 19

JO - PLANT AND SOIL

JF - PLANT AND SOIL

IS - 1-2

ER -