ABSTRACT
A large number of monocots (about 79%), dicots (83%), and all gymnosperms normally form mycorrhizal associations (Smith et al., 1997; Mukerji et al., 2000; Epstein and Bloom, 2005). On the other hand, plant roots from some families like Brassicaceae, that is, cabbage; Chenopodiaceae, that is, spinach; and Proteaceae, that is, macadamia nuts rarely form this association (Epstein and Bloom, 2005). Marschner (1995) also reported that mycorrhizae are rarely found or are even absent in certain families such as Cruciferae and Chenopodiaceae. Epstein and Bloom (2005) reported that mycorrhizal association did not occur under adverse environmental conditions like high salt concentration, ¬ooding, dry conditions, and soils having very high or low fertility. However, there may be some exceptions (Gupta and Kumar, 2000). For example, Brown and Bledsoe (1996) reported that the roots of a tidal salt marsh halophyte were colonized by arbuscular mycorrhizal fungi (AMF).
