Abstract: Soybean (Glycine max) is a major crop plant important for food supply and animal feed. Belonging to the legume family, it enters a complex symbiosis with soil bacteria called rhizobia, which results in the formation of a new root organ, the nodule. In this fascinating new organ the plantimprisoned rhizobia convert atmospheric nitrogen gas to valuable nitrogen fertiliser. Careful microbiology has isolated bacterial strains that help final seed yields as seen in Brazil. Modern genetics, biotechnology, physiology, biochemistry and genomics now have allowed the isolation of critical genes for the formation of the nodule. Together these studies indicate a novel molecular mechanism for the induction and subsequent control of cell division. Our research group has cloned the genes of two key soybean receptors for the rhizobial nodulation factor signal as well as molecular components of a complex roottoshoottoroot signaling loop involving peptide hormones, receptor kinases and small signaling metabolites. The findings suggest a new age of soybean improvement allowing for increased soybean yields and stress tolerance.

Key words: symbiosis, stem cells, nitrogen fertiliser, biofuel, protein supply, sustainability