Carbon and nitrogen antagonistically regulate multiple developmental processes. However, the molecular mechanism affecting nitrogen metabolism by sucrose transport remains poorly defined. Previously, we noted that Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11) mediated sucrose transport by binding to the promoter regions of Sucrose Transporter 1 (SUT1), Oryza sativa Sugars Will Eventually be Exported Transporters 11 (OsSWEET11), and OsSWEET14. Here, we note that OsDOF11 promotes nitrogen uptake and then maintains the ratio of fresh weight to dry weight in seedling plants and the effective leaf blade at flowering stages. Mutants of the sucrose transporter gene OsSWEET14 displayed a phenotype similar to that of OsDOF11. By microarray analysis and qRT-PCR in OsDOF11 mutant plants, OsDOF11 affected the transcription level of amino acid metabolism-related genes. We further found that mainly amino acid contents were reduced in flag leaves but increased in seeds. Both sugar and organic nitrogen changes caused the ratio of fresh weight to dry weight to decrease in OsDOF11 mutant seedling plants and mature leaves, which might result in vigorous reduced metabolic activity and become less susceptible to stress. These results demonstrated that OsDOF11 affected nitrogen metabolism by sugar distribution in rice, which provided new insight that OsDOF11 coordinated with C and N balance to maintain plant growth activity.

Micro-nanoparticles can enter the root tissue of plant cells along with the multiple lanes, and then accumulate in the tissue. But the plant physiological effect is still less studied. In this study, rice seedlings at germination stage were treated with 100 µM NaBiF 4 and BiF 3 . We found that exogenous application of NaBiF 4 treatment inhibited the elongation of rice roots and promoted the generation of adventitious roots, but treated BiF 3 did not mediate obvious phenotype. Further analysis of the peroxidase activity in related tissues showed that NaBiF 4 induced the activity of SOD and CAT decreased, and POD increased, while BiF 3 only induced the activity of SOD to reduced, but the activity of CAT and POD were no changed. Further analysis of the sodium element and potassium element concentration in tissues showed that only the NaBiF 4 treatment reduced content of potassium, but not sodium. Finally, stressrelated genes OsMT1, OsMT2, OsOVP1, OsNIP2;1, and OsMT2b were analyzed by Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). These results showed that NaBiF 4 induced the expression of OsMT2, OsOVP1, OsNIP2;1 decreased, and OsMT2b increased. However, BiF 3 only induced expression of OsMT1 increased. These results provide a physiological basis for further analysis of the effects of sodium salt-nanoparticles in crop plants.