Vesicular-Arbuscular Mycorrhizal Fungi of Wisconsin Sandy Soils

Abstract

Soils of the Great Lakes states are largely unexamined for vesicular-arbuscular mycorrhizal fungi (VAMF). Wisconsin, in particular, has no records of these fungi. There are only three reports (Koske, 1985; Koske et al., 1975, 1986) of VAMF being isolated from the great lacustrine dunes of North America, even though there are numerous reports of VAMF from North American maritime dune systems (e.g., for New England, Koske and Halvorson, 1981; Tews and Koske, 1986; and for the Northwest, Gerdeman and Trappe, 1974). The purpose of this study was to determine the species of VAMF present in dune soils of Lake Michigan and in sandy soils in Wisconsin and to compare the species lists with those of other dune systems. VAM fungi were collected from soil around the root zones of plants at 53 different sites. (FIG. 1 indicates the major collection sites.) The sites included dunes of Lake Michigan and Lake Superior, sandbars and banks of the Wisconsin River, and irrigated and unirrigated sandy soils of central Wisconsin. Samples (ca. 11) were collected from the following plants: Ammophila breviligulata Fern., Oct., 1983, July, 1984, June, 1985; Agropyron dasystachum (Hook.) Scrbn., July, 1984; Avena sp., June, 1985; Calamovilfa longifolia (Hook.) Scrbn., Oct., 1983, July, 1984; Glycine max L., July, 1985; Lathyrus maritimus (L.) Bigelow, Oct., 1983; Lythrum salicaria L., June, 1985; Poa praetensis L., July, 1984, June, 1985; Rosa sp., Oct., 1983; Zea mays L., June, 1985; sedges, June, 1985. Collection localities for each species are found in TABLE I. Soil samples were placed in plastic bags and stored at about 6 C until processed. Field observations regarding position, date, vegetational cover, and depth were recorded. Routinely, 2-3 root zones of each plant species were sampled at each site at a depth of 10-30 cm.