The arbuscular mycorrhizal fungus Glomus mosseae can enhance arsenic tolerance in Medicago truncatula by increasing plant phosphorus status and restricting arsenate uptake.
A pot experiment examined the biomass and As uptake of Medicago truncatula colonized by the arbuscular mycorrhizal (AM) fungus Glomus mosseae in low-P soil experimentally contaminated with different levels of arsenate. The biomass of G. mosseae external mycelium was unaffected by the highest addition level of As studied (200 mg kg(-1)) but shoot and root biomass declined in both mycorrhizal and non-mycorrhizal plants, indicating that the AM fungus was more tolerant than M. truncatula to arsenate. Mycorrhizal inoculation increased shoot and root dry weights by enhancing host plant P nutrition and lowering shoot and root As concentrations compared with uninoculated plants. The AM fungus may have been highly tolerant to As and conferred enhanced tolerance to arsenate on the host plant by enhancing P nutrition and restricting root As uptake.
Xu
Pengliang
P
Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094, China.
Christie
Peter
P
Liu
Yu
Y
Zhang
Junling
J
Li
Xiaolin
X
D001149:Arsenates / Q000493:pharmacokinetics / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D006540:Herbicides / Q000493:pharmacokinetics / Q000633:toxicity*; D046913:Medicago truncatula / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology; D038821:Mycorrhizae / Q000502:physiology*; D010758:Phosphorus / Q000493:pharmacokinetics; D018517:Plant Roots / Q000378:metabolism / Q000382:microbiology; D018520:Plant Shoots / Q000378:metabolism / Q000382:microbiology; D012989:Soil Pollutants / Q000493:pharmacokinetics / Q000633:toxicity*
D001149:Arsenates; D006540:Herbicides; D012989:Soil Pollutants; D010758:Phosphorus; C025657:arsenic acid