Present address: Danish Institute of Agricultural Science, Research Centre Aarslev, Kirstinebjergvej 10, DK-5792 Aarslev, Denmark;
Physiological and molecular evidence for Pi uptake via the symbiotic pathway in a reduced mycorrhizal colonization mutant in tomato associated with a compatible fungus
Article first published online: 16 AUG 2005
Volume 168, Issue 2, pages 445–454, November 2005
How to Cite
Poulsen, K. H., Nagy, R., Gao, L.-L., Smith, S. E., Bucher, M., Smith, F. A. and Jakobsen, I. (2005), Physiological and molecular evidence for Pi uptake via the symbiotic pathway in a reduced mycorrhizal colonization mutant in tomato associated with a compatible fungus. New Phytologist, 168: 445–454. doi: 10.1111/j.1469-8137.2005.01523.x
- Issue published online: 16 AUG 2005
- Article first published online: 16 AUG 2005
- Received: 21 April 2005 Accepted: 3 June 2005
- gene expression;
- Lycopersicon esculentum;
- P transport
- • A Lycopersicon esculentum mutant (rmc) is resistant to colonization by most arbuscular mycorrhizal fungi (AMF), but one Glomus intraradices isolate (WFVAM 23) develops arbuscules and vesicles in the rmc cortex. It is unknown whether the symbiotic phosphate (Pi)-uptake pathway is operational in this interaction.
- • Hyphal uptake of 32Pi and expression of plant Pi transporter genes were investigated in the rmc mutant and its wild-type progenitor (76R) associated with three AMF.
- • Hyphae transferred 32Pi in all symbioses with 76R and in the rmc–G. intraradices WFVAM 23 symbiosis. The other AMF did not colonize rmc. The Pi transporter-encoding LePT1 and LePT2 were expressed constitutively or in P-starved roots, respectively. The mycorrhiza-inducible Pi transporters LePT3 and LePT4 were expressed only in plants with AMF colonization and symbiotic 32Pi transfer.
- • LePT3 and LePT4 transcripts were reliable markers for a functional mycorrhizal uptake pathway in rmc. Our novel approach to the physiology and molecular biology of P transport can be applied to other arbuscular–mycorrhizal symbioses, irrespective of the size of plant responses.