Once the inorganic nitrogen enters into plant system, it tries to escape several times in the life cycle before it incorporated into grain. The amount of N recycled during lifecycle of plant is 100-fold higher than the N primarily acquired through agricultural input. The escaping N. is recycled by Glutamine synthetase, which existing in several isoforms in plant. Expression of any one isoform is not sufficient for efficient recycling of N. Simultaneous expression of OsGS 1.1 and OsGS2 genes together recycles N efficiently. These engineered rice lines thrive better in low input agriculture.