Effects of sea water on spore germination of a sand-dune-inhabiting arbuscular mycorrhizal fungus

Abstract

Gigaspora gigantea is a common arbuscu- lar mycorrhizal fungal species in sand dunes of the mid- and north-Atlantic coast of the U.S.A. where it is associated with dunegrasses and other species that disperse in seawater as vegetative fragments as well as species that disperse by seed or fruit. The ability of spores of G. gigantea to tolerate immersion in sea water would be important if the species relies on sea water as a medium for dispersal to adjacent coastal sites of primary succession. To test the effect of sea water on their germinability, spores of G. gigantea were immersed in sea water for 1, 2, 3, 4, 5, 10, 15 and 20 d and then incubated on filter paper moist- ened with deionized water. Germinabilty showed a slight but significant linear decrease with time, de- clining from ca 90% to 61% after 20 d.