Journal article
Effects of the mycorrhizal fungus ¤Glomus intraradices¤ on uranium uptake and accumulation by ¤Medicago truncatula¤ L. from uranium-contaminated soil
Phytostabilization strategies may be suitable to reduce the dispersion of uranium (U) and the overall environmental risks of U-contaminated soils. The role of Glomus intraradices, an arbuscular mycorrhizal (AM) fungus, in such phytostabilization of U was investigated with a compartmented plant cultivation system facilitating the specific measurement of U uptake by roots, AM roots and extraradical hyphae of AM fungi and the measurement of U partitioning between root and shoot.
A soil-filled plastic pot constituted the main root compartment (C-A) which contained a plastic vial filled with U-contaminated soil amended with 0, 50 or 200 mg KH2PO4-P kg(-1) soil (C-B). The vial was sealed by coarse or fine nylon mesh, permitting the penetration of both roots and hyphae or of just hyphae.
Medicago truncatula plants grown in C-A were inoculated with G. intraradices or remained uninoculated. Dry weight of shoots and roots in C-A was significantly increased by G. intraradices, but was unaffected by mesh size or by P application in C-B. The P amendments decreased root colonization in C-B, and increased P content and dry weight of those roots.
Glomus intraradices increased root U concentration and content in C-A, but decreased shoot U concentrations. Root U concentrations and contents were significantly higher when only hyphae could access U inside C-B than when roots could also directly access this U pool. The proportion of plant U content partitioned to shoots was decreased by root exclusion from C-B and by mycorrhizas (M) in the order: no M, roots in C-B > no M, no roots in C-B > M, roots in C-B > M, no roots in C-B.
Such mycorrhiza-induced retention of U in plant roots may contribute to the phytostabilization of U contaminated environments.
Language: | English |
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Publisher: | Kluwer Academic Publishers |
Year: | 2005 |
Pages: | 349-359 |
Journal subtitle: | An International Journal on Plant-soil Relationships |
ISSN: | 15735036 and 0032079x |
Types: | Journal article |
DOI: | 10.1007/s11104-005-2888-x |