Morphology ofEntomophthora muscae protoplasts grownin vitro

Summary Entomophthora muscae (C.) Fres. can be grownin vitro as protoplasts. Light and electron microscopical studies of thein vitro developed protoplasts have demonstrated the absence of an organized wall over the protoplasmic Con A-positive membrane at all stages of growth. The cytological organization is typical of the Entomophthorales with condensed chromatin in the interphase nuclei and small eccentric metaphase spindles. Long strands of endoplasmic reticulum, microubules and vesicles surrounding the plasmalemma may be involved in maintaining the precise shape ofE. muscae protoplast. Starvation of the fungus induces the formation of hyphal bodies after deposition of Con A- and WGA-positive wall material at the plasmalemma surface.Abbreviations Con A concanavalin A - DH Drosophila cell culture medium - FITC fluorescein isothiocyanate - GLEN glucose-lactal-bumin-yeast extract-NaCl culture medium for protoplasts - HBL hyphal body-like protoplasts - MM Mitsuhashi and Maramorosch' insect cell culture medium - PATAg periodic acid-thiocarbohydrazide-silver proteinate technique - PBN phosphate buffer with NaCl - S spherical protoplasts - WGA wheat germ agglutinin