GYPSY-MOTH IMMUNE DEFENSES IN RESPONSE TO HYPHAL BODIES AND NATURAL PROTOPLASTS OF ENTOMOPHTHORALEAN FUNGI

Gypsy moth hemocytes phagocytosed and/or encapsulated walled entomopht horalean cells and protoplasts that were regenerating cell walls but r arely recognized the healthy protoplasts that lack cell walls. Experim ents using lectin conjugates demonstrated different sugars localized a t the surface of protoplasts, regenerating protoplasts, and walled cel ls. Protoplasts had few sugars, in small amounts, on their surfaces an d these fungal cells evoked minimal cellular responses. Walled fungal cells had greater quantities of a variety of sugars in the cell walls and evoked the strongest defense response. Protoplasts of Entomophaga grylli, an orthopteran pathogen that cannot successfully develop in th e gypsy moth, Lymantria dispar, evoked a stronger hemocytic response i n larvae than protoplasts of the lepidopteran pathogen Entomophaga mai maiga that is able to successfully develop in L. dispar. Sugars detect ed at the surface of E. grylli and E. maimaiga protoplasts were simila r, so it is likely that the surface sugars we tested do not determine the differences in nonpathogen recognition between these fungal specie s. (C) 1996 Academic Press, Inc.