Plants as resource islands and storage units - adopting the mycocentric view of arbuscular mycorrhizal networks
2010
Lekberg, Ylva | Hammer, Edith Caroline | Olsson, Pål Axel
The majority of herbaceous plants are connected by arbuscular mycorrhizal (AM) fungi in complex networks, but how this affects carbon (C) and phosphorus (P) allocation among symbionts is poorly understood. We utilized a monoxenic AM system where hyphae from donor roots colonized two younger receiver roots of varying C status. AM fungal C allocation from donor to receiver compartments was followed by measuring the ¹³C contents in fungal- and plant-specific lipids, and P movement from a hyphal compartment was traced using ³³P. Four times more ¹³C was translocated from donor to C-limited receiver roots, but C remained in fungal tissue. Root C status did not influence the overall AM colonization, but arbuscule density was twice as high in non-C-limited roots, and they received 10 times more ³³P. The number of hyphal connections between compartments did not influence C and P allocation. Interestingly, there were more fungal storage lipids, but fewer structural lipids inside C-limited roots. Our results indicate that AM colonization may poorly reflect host quality as C can be supplied from neighboring roots. A mycocentric view of the symbiosis is proposed where C-delivering hosts are resource islands for the exchange of P for C, and C-limited hosts are storage units.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library