Genome-wide identification, evolution and expression analysis unveil the role of Dendrocalamus farinosus NRT genes in nitrogen utilization and nitrogen allocation

The rapid growth of Bamboo made the uptake and allocation of nitrogen much important. Nitrate is the main form that plant utilized nitrogen by nitrate transporters (NRTs) as well as ammonium salt. In this study, we identified 155 DfNRT genes which mapped to 32 chromosomes out of 35 chromosomes in Dendrocalamus farinosus. Collinearity analysis showed most NRT genes in D. farinosus paired with NRT genes in D. farinosus and P. edulis, which another two sequenced woody bamboo species, and the divergence was similar to the woody bamboo whole-genome duplication event. Through the ¹⁵N-nitrate trace analysis, we found that the nitrogen absorbed by roots in D. farinosus was preferentially distributed to above-ground parts, especially transported to leaves. DfNPF2.13 and DfNPF6.9 exhibited higher expression in leaf, and upregulated with extra N supply, suggesting they might be participating in N allocation between leaves in D. farinosus. This study provides a foundation for understanding the mechanism of nitrate transport and distribution in bamboo, and provide valuable information for improving bamboo nitrate absorption and promoting efficient nitrogen utilization.