Putative Allele of Gene Alters Rice Tiller Response to Nitrogen.

The number of tillers in rice significantly affects final yield, making it a key trait for breeding and nitrogen-efficient cultivation. By investigating agronomic characteristics, we analyzed phenotypic differences between the wild-type P47-1 and the mutant , performing genetic analysis and gene mapping through population construction and BSA sequencing. The mutant, exhibiting dwarfism and multiple tillering, is controlled by a single gene, , which is tightly linked to . A single base mutation (T to G) on chromosome 1 alters methionine to arginine, supporting as the candidate gene for . To investigate nitrogen response in tillering, KY131 (nitrogen-inefficient) and KY131 (nitrogen-efficient) materials differing in expression levels were analyzed. Promoter analysis of identified TCP19 as a nitrogen-responsive transcription factor, suggesting 's potential role in a TCP19-mediated nitrogen response pathway. Further analysis of P47-1, p47dt1, KY131, and KY131 under different nitrogen concentrations revealed 's distinct tiller response to nitrogen, altered nitrogen content in stems and leaves, and changes in expression. Additionally, and expression levels were lower in KY131 than KY131 under identical conditions. In summary, / appears to modulate nitrogen response and distribution in rice, affecting tiller response, possibly under TCP19's regulatory influence.