A survey of fungi associated with populations of cysts of Heterodera glycines from soybean field soils in four states in the Mississippi Valley and the southeastern United States indicates a generically diverse mycoflora, but one that is restricted in numbers of taxa and overlapping. Genera common in cysts from all localities include Fusarium, Gliocladium, Neocosmospora and Phoma. A species of Stagonospora, which we believe to be implicated as a significant natural parasite of H. glycines eggs, was also present in the four localities. Other fungi recovered with frequency from cysts in some, but not all soils surveyed, include species of Chaetomium, Codinaea heteroderae, Exophiala pisciphila, species of Thielavia, Verticillium lamellicola and a fungus referred to as a 'black yeast'. Several other incidental fungi were found rarely.
