The allele from a large-grain rice cultivar, Akita 63, increases yield and improves nitrogen-use efficiency.

The Green Revolution allowed a large amount of nitrogen (N) fertilization to increase crop yield but has led to severe environmental pollution. Therefore, increasing the crop grain yield must be achieved without such considerable input of N fertilization. A large-grain rice cultivar, Akita 63, significantly increased grain yield and improved N-use efficiency (NUE) for yield per amount of N absorbed by plants. This study found that the nonsense mutated gene, the allele of Akita 63, has a superior yield production with enlarged grain size. The allele increased the yield with improvements in harvest index and NUE for yields per plant N content by analyzing the near-isogenic line of rice plants with a large grain (LG-Notohikari), which was developed by introducing the allele of Akita 63 into normal-grain cultivar, Notohikari. Thus, the allele would be promising for further yield increase without additional large input of N fertilization in non--allele rice varieties.