Abstract
Mycelial elongation and protoplasmic flow rate in vitro were monitored for germinated spores of Gigaspora rosea and Glomus caledonium respectively, growing on membranes in microchambers, by using a combination of time-lapse and video-enhanced light microscopy and image analysis. The microchambers allowed continuous observation of living mycelium over a period of several hours during which protoplasm flow and bidirectional movements of cellular organelles and particles were monitored in individual hyphae. Growth rate of G. rosea hyphae, calculated 8 days after germination, was 2.64 μm/min. Protoplasmic flow rate, measured on the basis of the movement of particles, ranged from 2.98 to 4.27 μm/s in living hyphae of G. caledonium. We showed that G. rosea, when growing in axenic culture in the absence of the host, ceased growth within 8 days of germination and underwent a process of protoplasm retraction from hyphal tips, leading to the formation of empty mycelial segments. A process of resource reallocation was inferred in spores of G. rosea showing multiple germination. Detailed developmental studies of living hyphae by using microchambers could provide useful information on spatio-temporal dimensions of cellular events occurring in arbuscular mycorrhizal fungi.
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Giovannetti, M., Sbrana, C. & Logi, C. Microchambers and video-enhanced light microscopy for monitoring cellular events in living hyphae of arbuscular mycorrhizal fungi. Plant and Soil 226, 153–159 (2000). https://doi.org/10.1023/A:1026415419193
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DOI: https://doi.org/10.1023/A:1026415419193