Moderating mycorrhizas: arbuscular mycorrhizas modify rhizosphere chemistry and maintain plant phosphorus status within narrow boundaries

• DOI: 10.1111/pce.12207
• Publication Date: 2013-10-12T01:44:11Z
• Authors: NAZANIN K. NAZERI; HANS LAMBERS; MARK TIBBETT; MEGAN H. RYAN
• Keywords: Trifolium subterraneum

Pastures often experience a pulse of phosphorus (P) when fertilized. We examined the role arbuscular mycorrhizal fungi (AMF) in uptake P from pulse. Five legumes (Kennedia prostrata, Cullen australasicum, Bituminaria bituminosa, Medicago sativa and Trifolium subterraneum) were grown moderate P, sterilized field soil, either with (+AMF) or without (-AMF) addition unsterilized soil. After 9-10 weeks, half pots received 15 mg kg(-1) One week later, we measured: shoot root dry weights; percentage length colonized by AMF; plant nitrogen manganese (Mn) concentrations; rhizosphere carboxylates, pH plant-available P. The raised concentration similar amount uncolonized plants, but increased 143% plants 53% plants. Inoculation AMF decreased carboxylates 52%, ∼0.2-0.7 units lowered Mn 38%. conclude that are not simply means for to enhance is limiting, also act maintain within narrow boundaries can affect nutrient through their influence on chemistry.