Synergistic Interaction between Copper and Nitrogen-Uptake, Translocation, and Distribution in Rice Plant.

Interactions among nutrients have been widely recognized in plants and play important roles in crop growth and yield formation. However, the interplay of Cu and N in rice plants is not yet clear. In this study, rice plants were grown with different combinations of Cu and N supply. The effects of Cu-N interaction on the growth, yield production, Cu and N transport, and gene expression levels were analyzed. The results showed that the effect of N supply on rice growth and yield formation was more pronounced than that of Cu supply. The Cu supply significantly improved the uptake of N (by 9.52-30.64%), while the N supply significantly promoted the root-to-shoot translocation of Cu (by 27.28-38.45%) and distributed more Cu (1.85-19.16%) into the shoots and leaves. The results of qRT-PCR showed that +Cu significantly up-regulated the expression levels of both NO 3 - and NH 4 + transporter genes OsNRTs and OsAMTs , including OsNRT1.1B , OsNRT2.1 , OsNRT2.3a , OsNRT2.4 , OsAMT1.2 , OsAMT1.3 , and OsAMT3.1 . Meanwhile, +N significantly up-regulated the expression levels of Cu transporter genes OsHMA5 and OsYSL16 . In addition, the supply of Cu up-regulated the expression levels of OsGS1;2 , OsGS2 , and OsNADH-GOGAT to 12.61-, 6.48-, and 6.05-fold, respectively. In conclusion, our study demonstrates a synergistic effect between Cu and N in rice plants. It is expected that our results would be helpful to optimize the application of N and Cu fertilizers in agriculture.