Record ID No. |
568 |
Author(s) |
Bingyun W.U., Kazuhide Nara., Taizo Hogetsu , 2002 |
Affiliation |
Research Unit for symbiotic function, Asian Natural Environmental Science center, The University of Tokyo, Midori-cho 1-1-8, Nishitokyo, tokyo 188-0002, Japan |
Title |
Spatiotemporal transfer of carbon-14-labelled photosynthate from ectomycorrhizal Pinus densiflora seedlings to extraradical mycelia |
Source. Vol.(no):Page |
Mycorrhiza, 12(2),83-88p. |
Categories |
Ectomycorrhiza |
Subjects |
Soil plant relations |
Sub-subjects |
Nutrition |
Host |
Pinus densiflora |
Organism |
n.a. |
Country |
Japan, Asia |
Abstracts |
Seedlings of Pinus densiflora colonized by an
unidentified ectomycorrhizal fungus (T01) were labelled
photosynthetically with 14C. Movement of 14C-labelled
photosynthates within the underground part of the seedlings was
investigated by temporal autoradiography using an imaging plate.
Within 1 day, 14C was transferred from the shoot to the
underground part that included roots, mycorrhizae, and the
extraradical mycelium; within 3 days, the 14C in the underground
part reached its maximum density. Mycorrhizae and actively
growing root tips were large C sinks. Three days after 14C
labelling, counts of 14C radioactivity in the underground part
of the mycorrhizal seedlings were 2.6 times those of
nonmycorrhizal seedlings. The mycorrhizae of mycorrhizal plants
accumulated 5.2 times the 14C counts in the short-root tips of
nonmycorrhizal plants. 14C counts in various areas of the
extraradical mycelium demonstrated that all 14C-photosynthate
transfer from the host root to the extraradical mycelium
occurred within 3 days after 14C labelling, and that there was
only a short lag of <1 day between 14C accumulation in the basal
and distal parts of the mycelium. Although more 14C accumulated
in the distal than in the basal parts, 14C counts per unit
hyphal biomass were similar between the two. These results
suggest that 14C spread rapidly throughout the entire mycelium.
Thirteen days after 14C labelling, we estimated 14C allocation
to extraradical mycelia by taking autoradiographs after removing
host roots. About 24% of 14C counts in the underground part of
the mycorrhizal seedlings had been allocated to extraradical
mycelia in this system, indicating that the fugal mycelium is an
important sink for photosynthates.
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