Cyclic AMP, Radioimmunoassay, Phytoalexins, Glycine max, Phytophthora megasperma cAMP levels were monitored in soybean (Glycine max) infected with race 1 of Phytophthora megasperma f. sp. glycinea and in soybean cell suspension cultures treated with a glucan elicitor from P. megasperma. While cAMP could be readily detected in soybean hypocotyls using a radio immunoassay, no correlation was obs...