CAJ | 학술논문

An experiment was carried out to study the transport process of nitrogen (N) assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15N-NO3 and 15N-NH4 were fed to the root of tea plants (Camellia sinensis L.).Results showed that the main amino acids were glutamine,theanine,arginine,asparic acid and glutamic acid,which accounted for 49e/0,17%,8%,7%,and 4%,respectively,of the total amino acids in the xylem sap.After the tea plants were fed with 15N-NO3 and 15N-NH4 for 48 h,the amount of total amino acids in xylem sap significantly increased and those fed with 15N-NH4 had higher increment than those with 15N-NO3.Two hours after 15N-NO3 and 15N-NH4 were fed,15N abundance in glutamine,asparagine,glutaxnic acid,aianine,and arginine were detected and increased quickly over time.This indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots,incorporated into the above amino acids and transported to the xylem sap.Rapid increase in 15N-NO3 in the xylem sap of tea plants fed with 15N-NO3 indicated that nitrate could be directly transported to the xylem sap.Glutamine,theanine,and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15N-NO3 and 15N-NH4.