ABSTRACT
Object To study the callus culture of Gynura segetum (Lour.) Merr., so as to lay the foundation for the rapid propagation of its breeds.Methods The explants used in culture were root, stem and leaf of G. segerum. The MS basal medium containing different plant hormones was applied. Results The best explants were leaf of G. segetum. The medium induced callus was MS basal medium containing 1 0 mg/L NAA and 4 0 mg/L 6 BA and the callus induction rate was 64% . The sprouting rate of the callus transplanted to fitting differential medium was 86 7%.Conclusion The rapid propagation of G. segetum can be carried out by inducing callus of the plant.
ABSTRACT
Object To study the effect of pH on callus tissue growth and paclitaxel content of Taxus cuspidata Sieb. et Zucc. and Taxus chinensis var. mairei (Lemee et Le ′vl.) Cheng et L. K. Fu Methods The callus tissues were cultured on B5 medium with defferent pH values, and the growth rate, PAL activity and paclitaxel content were determined. Results Different callus tissues of taxus need different optimum pH values. The pH values, which could promote callus growth significantly, were all inhabitory to PAL activity and accumulation of paxlitaxel. Conclusion pH had great influences on the growth of the callus and the level of secondary metabolism, thereby the synthesis and accumulation of paclitaxel were affected.