Soybean Root Response to Symbiotic Infection Glyceollin I Accumulation in an Ineffective Type of Soybean Nodules with an Early Loss of the Peribacteroid Membrane

Abstract

A glyceollin I accumulation of about 6000 pmol · mg dry weight^-, a tenfold increase above control root tissue, was found in one type of nodule from Glycine max which had been infected with a fix^- strain (61-A-24) of Rhizobium japonicum. In nodules infected with one other ineffective (fix^-) strain of Rhizobium japonicum (RH 31-Marburg) or with two fix⁺ strains of Rhizobium japonicum (61-A-101 and USD A 110) no increase in glyceollin I concentrations above control values was found at either 20 d or 34 d after infection. Nodules infected with Rhizobium japonicum 61-A-24 are distinguished by an early loss of the peribacteroid membrane in the infected host cell, whilst the bacteroids themselves remain stable.