Abstract
A simple and convenient culture system has been developed for the analysis of ectomycorrhiza formation under controlled conditions. Rapid and synchronous mycorrhiza synthesis was observed when thin and even layers of Pisolithus tinctorius (Pers.) hyphae were brought at once into contact with the entire root system of 3-month-old Picea abies (L. Karst) plants. Suitable fungal layers were grown on cardboard with limiting glucose supply in the medium to maximize radial growth. The glucose was almost consumed by the time the fungus had spread over the whole cardboard and was ready for inoculation of the roots. At this stage, the fungus contained trehalose and arabitol as the main soluble carbohydrates. A few hours after the assembly of the culture system, contacts between roots and aerial hyphae were observed and a sheath was formed 3 days later, suggesting very rapid ectomycorrhiza formation under these conditions. The pool of soluble carbohydrates of the inoculum, i.e. the extramatrical mycelium, declined after inoculation of the roots and was almost zero after 2 weeks. The supply of carbon by the plant was then sufficient for the fungus to expand the soluble pool efficiently in both the mycorrhizas and the extramatrical mycelium. The kinetics of the carbohydrate pool and the observed differentiation of the short roots to mycorrhizas imply that in our culture system fully functional symbiosis was established no later than 14 days after the plants were inoculated with the fungus.
Similar content being viewed by others
References
Fortin JA, Piche Y (1980) Technique for the observation of early morphological changes during ectomycorrhiza formation. Can J Bot 58:361–365
Frehner M, Keller F, Wiemken A (1984) Localization of fractan metabolism in the vacuoles isolated from protoplasts of Jerusalem artichoke tubers (Helianthus tuberosus L.). J Plant Physiol 116:197–208
Grellier B, Letouze R, Strullu DG (1984) Micropropagation of birch and mycorrhizal formation in vitro. New Phytol 97:591–599
Holligan DM, Jennings DH (1972) Carbohydrate metabolism in the fungus Dendryphiella salina. I. Changes in the levels of soluble carbohydrates during growth. New Phytol 71:569–582
Horan DP, Chilvers GA, Lapeyrie FF (1988) Time sequence of the infection process in eucalypt ectomycorrhizas. New Phytol 109:451–458
Kottke I, Guttenberg M, Hampp R, Oberwinkler F (1987) An in vitro method for establishing mycorrhizae on coniferous tree seedlings. Trees 1:191–194
Lewis DH (1989) Fungi and sugars: a suite of interactions. Mycol Res 95:897–904
Lewis DH, Harley JL (1965) Carbohydrate physiology of mycorrhizal roots of beech. II. Utilization of exogenous sugars by uninfected and mycorrhizal roots. New Phytol 64:238–255
Martin F, Ramstedt M, Söderhäll K, Canet D (1988) Carbohydrate and amino acid metabolism in the ectomycorrhizal ascomycete Sphaerosporella brunnea during glucose utilization. Plant Physiol 86:935–940
Marx DH (1969) The influence of ectotrophic mycorrhizal fungi on the resistance of pine roots to pathogenic infections. I. Antagonism of mycorrhizal fungi to root pathogenic fungi and soil bacteria. Phytopathology 59:153–163
Marx DH, Zak B (1965) Effect of pH on mycorrhizal formation of slash pine in aseptic culture. For Sci 11:66–69
Niederer M, Pankow W, Wiemken A (1989) Trehalose synthesis in mycorrhiza of Norway spruce: an indicator of vitality. Eur J For Pathol 19:14–20
Nylund JE, Unestam T (1982) Structure and physiology of ectomycorrhizae. I. The process of mycorrhiza formation in Norway spruce in vitro. New Phytol 91:63–79
Wiemken A (1990) Trehalose in yeast, stress protectant rather than reserve carbohydrate. Antonie Leeuwenhoek J Microbiol 58:209–217
Wiemken V, Ineichen K, Wiemken A (1990) Effect of several fungi (pathogenic, neutral) on bare roots and mycorrhizal roots (Pisolithus tinctorius) of Picea abies seedlings: transpiration of the plants and accumulation of the stress metabolite ACC (aminocyclopropane carboxylic acid). Physiol Plant 79:A99
Wong KY, Fortin JA (1989) A Petri dish technique for the aseptic synthesis of ectomycorrhizae. Can J Bot 67:1713–1716
Yang CS, Wilcox HE (1984) Technique for observation of mycorrhizal development under monoxenic conditions. Can J Bot 62:251–254
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Ineichen, K., Wiemken, V. Changes in the fungus-specific, soluble-carbohydrate pool during rapid and synchronous ectomycorrhiza formation of Picea abies with Pisolithus tinctorius . Mycorrhiza 2, 1–7 (1992). https://doi.org/10.1007/BF00206277
Issue Date:
DOI: https://doi.org/10.1007/BF00206277