ABSTRACT
The research frontier on soybean N2 fixation will be synthesized proceeding from the molecular level to the cellular level asymbiotic N2 fixation, specificity, lectins and infection to the legume microsymbiont association. Rhizogenetics is the study of genetic control over plant below ground structures. There is little information in reference of rhizogenetics of soybean. With the possible exception of the few non-nodulating genes which have been discovered, and the occasional reference to differences in nutrient uptake, gross root morphological differences, or fluorescence of roots, this area has been little studied. Soybean culture continues to expand into alien countries, virgin soils and unaccustomed climates. Success in the program depends not only on prudence in selecting the host genotype, but also in the selection and use of the microsymbiont, Rhizobiurm japonicum, which produces the nodules and supplies the nitrogen for seed development. Nodulation establishment in soybeans is influenced by environmental, rhizobial and host symbiont factors.
