Abstract
Soybean (Glycine max) is one of the most important crops worldwide. Root nodule symbiosis between soybean and rhizobia has been extensively exami-ned due to its significance for agricultural productivity and environmental sustainability. Recent advances have enhanced our understanding of the soybean genotypes known as the Rj/rj genotypes, which play a critical role in regulating root nodule symbiosis. Furthermore, the function of rhizobium-secreted proteins, termed effectors, in eliciting specific responses in soybean Rj/rj genotypes has been elucidated. This review summarizes the involvement of soybean Rj/rj genotypes and their corresponding root nodule bacterial effectors in the regulation of nodule formation. We also discussed the potential for manipulating root nodule symbiosis by applying Rj/rj genotypes in soybean breeding programs, which may enhance nitrogen fixation efficiency and subsequently reduce the need for chemical fertilizers and greenhouse gas emissions from agricultural land.