RESUMEN
This paper aimed to study the effect nitrogen supplying on biomass accumulation and root respiration dynamic change of Glycyrrhiza uralensis and reveal the metabolic pathway of root respiration impact the biomass accumulating of G. uralensis. Six groups of one-year-old G. uralensis were fertilized with total nutrition containing various nitrogen concentration (0, 0.5, 1, 2, 4, 8 mmol x L(-1)) every week. At the end of every month, from June to October, the volume respiration rate and biomass of different classes of root samples were determined, and the correlation between root respiration and biomass was analyzed. The results indicated a negative correlation between volume respiration rate and biomass, nitrogen supply significantly affected both root respiration and biomass of G. uralensis by reducing root respiration and increasing root biomass. Under 8 mmol x L(-1) nitrogen supplying, there existed the optimal inhibition of root respiration, which has increased biomass of G. uralensis.