Abstract
Morphology of acervuli, perithecia, conidia, and ascospores, development and morphology of appressoria, and discharge of ascospores of Glomerella glycines were studied on soybean (Glycine max) and in culture. Colletotrichum destructivum was shown to be the anamorph of G. glycines. Appressorial development and morphology are described for the first time. Sodium chloride-yeast extract agar was used for culturing acervuli of C. destructivum, potato-dextrose agar for culturing the perithecia of G. glycines, and NaCl-yeast extract agar plus sucrose for culturing the fruiting structures of both forms. Colletotrichum truncatum did not produce the teleomorph, G. glycines, on any of the media tested. C. destructivum and G. glycines produced no symptoms in soybean tissues, but isolates from soybean pods and stems were pathogenic to soybean unifoliolate leaves in reinoculation studies.