In ̄uence of Root-Applied Epibrassinolide and Carbenoxolone on the Nodulation and Growth of Soybean (Glycine max L.) Seedlings

24-Epibrassinolide belongs to the brassinosteroid family of plant hormones, and carbenoxolone is a synthetic analogue of glycyrrhizic acid that inhibits enzymes important in steroid and prostaglandin action in animals. The e€ect of these compounds on root nodulation, root growth and shoot growth of Glycine max (L.) Merr. cv. Tracy M was examined. Epibrassinolide reduced total nodulation, plant wet weight, root length, shoot length, ®rst internode length and number of lateral roots. E€ects were observed at concentrations as low as 0.1 lM. Carbenoxolone reduced lateral root formation, but did not reduce nodule numbers, root length or weight, nor stem length or weight.