Objective: Selecting the best N concentrations for the growth of the Chinese goldthread(Coptis chinensis).
Method: Employing sand culture procedures.
Result: The symptoms of shortage of nitrogen were reduced in low N(1/5 N) solution, but the new roots and aerial parts were adversely affected in over nitrogen solution(2 N); the activity of NR in leaves and the content of berberine in rhizome were also low in 2 N solution; the range of optimum N concentrations for growth and high contents of effective components is 1/2 N to 1 N.
Conclusion: The consumption of nitrogen by Coptis chinensis is lower in the period of maximum contents of effective components in rhizome than in the period of luxuriant growing of the plant.