Co-Authors:
Hirsch, A.M., Dept. of Molec. Cell and Devmtl. B., Molecular Biology Institute, University of California, Los Angeles, CA 90095-1606, United States
Kapulnik, Y., Institute of Field and Garden Crops, Agricultural Research Organization, Volcani Center, Bet Dagan, 50-250, Israel
Abstract:
A number of genera of soil fungi interact with plant roots to establish symbiotic associations whereby phosphate acquired by the fungus is exchanged for fixed carbon from the plant. Recent progress in investigating these associations, designated as mycorrhizae (sing., mycorrhiza), has led to the identification of specific steps in the establishment of the symbiosis in which the fungus and the plant interact in response to various molecular signals. Some of these signals are conserved with those of the Rhizobium-legume nitrogen-fixing symbiosis, suggesting that the two plant-microbe interactions share a common signal transduction pathway. Nevertheless, only legume hosts nodulate in response to Rhizobium, whereas the vast majority of flowering plants establish mycorrhizal associations. The key questions for the future are: what are the signal molecules produced by mycorrhizal fungi and how are they perceived by the plant?.