Natural variation of OsWRKY23 drives difference in nitrate use efficiency between indica and japonica rice
Siyu Zhang, Zhe Ji, Jiao Wu, Chengbo Shen, Yaojun Qin, Yun‐Zhi Huang, Menghan Huang, Shuming Kang, Xuan Liu, Shunqi Li, Zulong Mo, Ying Yu, Bingyu Jiang, Yanan Tian, Longfei Wang, Qingxin Song, Shaokui Wang, Shan Li, Shan Li, Shan Li
Abstract
Between the two major rice subspecies, indica varieties generally exhibit higher nitrate (NO3‒) uptake and nitrogen (N)-use efficiency (NUE) than japonica varieties. Introducing efficient NO3‒ utilization alleles from indica into japonica could improve NUE, and at the same time uncover unknown regulators of NO3‒ metabolism. Here, we identify OsWRKY23 as a key regulator of NO3‒ uptake and NUE differences between indica and japonica rice. The OsWRKY23indica allele exhibits reduced transcriptional activation of a negative regulator of auxin accumulation, DULL NITROGEN RESPONSE1 (DNR1). The resultant increase in auxin level improves NO3‒ uptake and assimilation, which ultimately enhances grain yield. Geographical and evolutionary analyses reveal overlapping distribution of OsWRKY23indica and DNR1indica, particularly in low-fertility soils, suggesting their involvement in the adaptation to low N conditions to improve NUE and grain yield. Incorporating the OsWRKY23-DNR1 module from indica rice represents a promising strategy to enhance japonica NUE, which is crucial for sustainable agriculture. Rice indica varieties have higher nitrogen use efficiency (NUE) than that of japonica varieties. Here, the authors show that natural variation of OsWRKY23 and its interaction with DULL NITROGEN RESPONSE1 (DNR1)-mediated auxin accumulation play a role in NUE divergence between the two rice subspecies.