Fungi Associated with Several Developmental Stages of Heterodera glycines From an Alabama Soybean Field Soil

An examination of young, swollen, cream-colored cysts of Heterodera glycines Ichinohe attached to root surfaces and of white, newly exposed females partly immersed within roots of Alabama-grown soybeans [Glycine max (L.) Merr.] revealed the presence of a number of fungal pathogens. Fungi most frequently isolated from these stages of development were: Chaetomium cochliodes Palliser, Exophiala pisciphila McGinnis & Ajello, Fusarium oxysporum Schlecht, F. solani (Mart.) Sacc., Phytophthora cinnamoni Rands, Pythium sp., a sterile mycelium, and Trichosporon beigelii (Kuchenm. & Rabenh.) Vuill. Fifty percent of the cream-colored cysts were infected as compared to 20 percent of the younger white, lens-shaped females. An examination of sausage-shaped females within roots and brown cysts from soil indicated that two and 70 percent respectively were invaded by fungi. Results indicated that a progressive increase in fungal colonization occurred with nematode development. Some overlapping of the