Water mimosa (Neptunia oleracea Lour.) can fix and transfer nitrogen to rice in their intercropping system.

The amount of N fixation by water mimosa was 4.38-13.64 mg/pot, and the N transfer from water mimosa to rice was 3.97-9.54 mg/pot. This can promote the growth of rice and reduce the application of N fertilizer. We suggest that the rice-water mimosa intercropping system is a sustainable ecological farming approach and can be applied in the field to facilitate rice production. © 2021 Society of Chemical Industry.