14C transfer between the spring ephemeral Erythronium americanum and sugar maple saplings via arbuscular mycorrhizal fungi in natural stands

Abstract

We investigated in the field the carbon (C) transfer between sugar maple (Acer saccharum) saplings and the spring ephemeral Erythronium americanum via the mycelium of arbuscular mycorrhizal (AM) fungi. Sugar maple saplings and E. americanum plants were planted together in pots placed in the ground of a maple forest in 1999. Ectomycorrhizal yellow birches (Betula alleghaniensis) were added as control plants. In spring 2000, during leaf expansion of sugar maple saplings, the leaves of E. americanum were labelled with CO. Seven days after labelling, radioactivity was detected in leaves, stem and roots of sugar maples. Specific radioactivity in sugar maples was 13-fold higher than in yellow birches revealing the occurrence of a direct transfer of C between the AM plants. The quantity ofC transferred to sugar maple saplings was negatively correlated with the percentage of C allocated to the storage organ of E. americanum. A second labelling was performed in autumn 2000 on sugar maple leaves during annual growth of E. americanum roots. Radioactivity was detected in 7 of 22 E. americanum root systems and absent in yellow birches. These results suggest that AM fungi connecting different understorey species can act as reciprocal C transfer bridges between plant species in relation with the phenology of the plants involved.

Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs

“…Numerous studies have shown that AM fungi can enhance the P nutrition of host plants, increase the diversity and stability of plant communities, and enhance the resistance of host plants to abiotic stresses such as drought and salt stress [16,[41][42][43] . Until now, few studies have been carried out on the mycorrhizal status of ephemeral plants that play an important role in the stability of desert ecosystems.…”

The Role of Mycorrhizas in Forest Soil Stability with Climate Change

“…Forest ecosystems are dynamic, and this is illustrated by dynamic patterns and processes in mycorrhizal networks. Not only do the complexity and composition of mycorrhizal networks change over time (Twieg et al, 2007), but belowground fluxes of nutrients change over the growing season with shifts in source-sink gradients among networked plants (Lerat et al, 2002). Using dual 13 C/ 14 C labelling in the field, Philip (2006) found that the direction of net carbon transfer reversed twice over the growing season: (1) from shooting Douglas-fir to bud-bursting birch in spring; (2) then reversing, from nutrient and photosynthateenriched paper birch to stressed understory Douglas-fir in summer; and (3) reversing again, from still-photosynthesizing Douglas-fir to senescent paper birch in the fall.…”

Mycorrhizal networks and complex systems: Contributions of soil ecology science to managing climate change effects in forested ecosystems

“…Complex systems are dynamic, and this is illustrated by dynamic patterns and processes in mycorrhizal networks. Not only do the complexity and composition of mycorrhizal networks change over time (Twieg et al 2007), but below-ground fluxes of nutrients change over the growing season with shifts in source-sink gradients among networked plants (Lerat et al 2002). Using dual 13 C/ 14 C labelling in the field, Leanne Philip found that the direction of net carbon transfer reversed twice over the growing season: (1) from shooting Douglas-fir to bud-bursting birch in spring; (2) then reversing, from nutrient and photosynthate-enriched paper birch to stressed understory Douglas-fir in summer; and (3) reversing again, from still-photosynthesizing Douglasfir to senescent paper birch in the fall (Philip 2006) (Fig.…”