Abstract
β-Phenethylamine (β-PEA) is an aromatic amine which has been detected as a component of alkaloids in cactus and in perennial legumes. We reported the occurrence of β-PEA in root nodules of various leguminous crops. Broad survey of nodulated plants showed that β-PEA was detected in the root nodules formed with genus Bradyrhizobium. Among the legumes, peanut, known as a legume that closely associates with Bradyrhizobium sp., was an exceptional legume which contained little β-PEA. We examined again the presence of β-PEA in peanut nodules together with soybean nodules collected from various cultivars grown at different locations. To clarify the mechanism of β-PEA production, nodule bacteria were isolated from soybean and peanut plants, and cross-inoculation test was carried out. As a result, it was found that β-PEA production in root nodules depends not only on the infected bradyrhizobia but also on the inducing factor from their host plants.
