【Objective】The study was conducted to discuss the physiological and biochemical responses of potato
treated with different nitrogen concentrations and explore the genes related to nitrogen metabolism, and identify the key
period when potato was affected by nitrogen and the expression differences of nitrogen metabolism genes during this
period.【Method】Taking Yanshu No. 4 potato as the test material, the nitrogen efficiency, physiological and biochemical
differences as well as the key growth and development period of potato were studied by pot planting under nitrogen and non- nitrogen treatments. In addition, transcriptome sequencing was performed on leaves and roots of potato at bud stage to obtain
differentially expressed genes of nitrogen metabolism.【Result】Nitrogen treatment significantly increased potato nitrogen
efficiency, soluble sugar content, soluble protein content, root activity, nitrate reductase activity and glutamine synthase
activity. Meanwhile, the bud stage was a key period of potato growth and development. There were a total of 12 996 DEGs
including 6 440 up-regulated and 6 556 down-regulated in leaves and roots treated with nitrogen. GO was enriched in 11
biological processes, 17 cell components and 2 molecular functions, and there were 15 DEGs including 8 up-regulated and
7 down-regulated in nitrogen metabolism pathways. There were a total of 12 178 DEGs in leaves and roots without nitrogen
application, including 6 268 were up-regulated and 5 910 were down-regulated. GO was enriched in 7 biological processes,
21 cell components and 2 molecular functions, and there were 19 DEGs including 8 up-regulated and 11 down-regulated
in nitrogen metabolism pathways. The nitrogen metabolism pathway identified 19 DEGs encoding 9 genes, in which 7 DEGs
(PGSC0003DMG400016996, PGSC0003DMG400006913, PGSC0003DMG400030212, PGSC0003DMG400025823,
PGSC0003DMG400016001, PGSC0003DMG400004355, PGSC0003DMG400009698)had high expression in leaves,
meanwhile, the other 7 DEGs(PGSC0003DMG400015734, PGSC0003DMG400001145, PGSC0003DMG400008262,
PGSC0003DMG400008356, PGSC0003DMG400014592, PGSC0003DMG400013235, Novel02273)had high expression
in roots.【Conclusion】NRT2.4, NRT2.5, NRT2.7, NR and NiR genes are mainly involved in nitrogen absorption function of
potato, while GdH, GS and GOGAT genes are mainly involved in nitrogen utilization function of potato. |