Research Team Discovers Gene that Impacts Soybean Nodule Development

In a study that aims to increase soybean plants' nitrogen-fixing ability, and thus reduce the need for chemical fertilizers, a research team from the University of South Dakota has discovered that the gene SUR2 plays a key role in the production of auxin, a hormone that affects nodule development in soybean plants.

Soybean interacts with bacteria in the soil to form nodules. Within the nodules, two distinct zones—one that fixes nitrogen, and another that transports it to the plant—are formed from pre-existing root cells. The expression of specific genes in a particular root cell determines its function.

Led by associate plant science professor Senthil Subramanian, the team has previously observed that auxin reduced the number of nodules in soybean plants. Doctoral student Suresh Damodaran then focused on identifying genes that regulate auxin levels in the nodules. When Damodaran reduced the expression of the SUR2 gene, thus increasing auxin production, the plant produced fewer nodules. However, when auxin levels were reduced, the nodule numbers increased.

For more details, read the article at AgroNews.