Abstract
Hyphal branches of the primary germ tubes and secondary hyphae of Gigaspora gigantea, Gigaspora rosea, and Glomus intraradices were induced by exposure to light. The photo- induced branching of G. rosea was increased if the germinated spores were first grown in the presence of 10 μM quercetin before exposure to light. Further analyses with G. gigantea showed that at low intensity light (13.4 μE s-1m-2), maximum branching was achieved after a 6 h exposure and at high intensity light (10,800 μE s-1m-2), maximum branching was reached after an 8 min exposure. Multiple exposures to alternating low light followed by a dark incubation period indicated that the photo-effect was not additive. Photo-induced branching did not need a subsequent dark period for the growth of hyphal branches because branching occurred during prolonged continuous light. The light-induced branching appeared to have ecological relevance. Corn seedlings (Zea maize L.) grown in AM fungal inocula exposed to light had a higher percentage of their root system colonized by G. gigantea than those in inocula that remained in the dark.
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Nagahashi, G., Douds, D. & Buee, M. Light-induced hyphal branching of germinated AM fungal spores. Plant and Soil 219, 71–79 (2000). https://doi.org/10.1023/A:1004714530021
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DOI: https://doi.org/10.1023/A:1004714530021