Gene Expression in Plant-Endomycorrhizal Fungal Communication

Vesicular arbuscular mycorrhizal (AM) fungi have been recognized as obligate symbionts of about 80% of the land plants in most ecosystems. The symbiosis is biotrophic and is normally mutualistic; the compatible interactions are based on nutritional transfer between the symbiotic partners. Changes in plant gene expression during the early stages of the mycorrhizal symbiosis have been described (van Rhijn et al., 1997), as well as low-level or transient defense responses (Bonfante-Fasolo, Perotto 1990; David et al., 1998; Gianinazzi-Pearson et al., 1995; Harrison, Dixon 1994; Kapulnik et al., 1996; Lambais, Mehdy, 1993; Volpin et al., 1994; 1995).