Abstract:

In the protoplast culture of Populus simonii Carr. ,the variations in contents of IAA, GA₃, CTK, ABA four kinds of endogenous hormones in the calli differentiated from four differentiation culture media were determined by the high pressure liquid chromatography method, and the biochemical reactions of nitrogen related to them were also tested. It was shown that there was a great change in the contents and kinds of the endogenous houmones among the calli differentiated from the different media. The treatment which resulted in the higher content and more kinds of CTK, and the higher ratio of CTK/IAA within the calli was favourable to the calli differentiation, whereas if the ABA was contented in calli, the differentiation of the calli was inhibited. During their differentiation process, a mutually exclusive relation between the activity of nitrate reductase(NR) and the amino-N content was found, in the calli with higher differentiation frequancy the NR activity was low, but the amino-N content was high.

Key words: Populus simonii carr., Protoplast cultures, Endogenous hormones, Differentistion frequency