Evaluation of rooting characteristics of Ephedra cuttings by anatomy and promising strain selection based on rooting characteristics and alkaloid content.

The differences in rooting characteristics of cuttings prepared from E. sinica strains were investigated and found that cuttings prepared from strains with high rooting characteristics showed approximately 90% of the cuttings were rooted, whereas cuttings prepared from low rooting characteristics did not root. To understand the reason for this substantial difference, the anatomy of nodes was examined and found that adventitious roots were generated from the cortex and parenchyma in pith. Calculations of the correlation coefficients between the rooting rate and the value of anatomy indicated that the rooting rate was positively correlated with the parenchyma in pith in the node. On the basis of the positive correlation, it is possible to estimate the rooting characteristics of new strains without having to prepare cuttings. Next, we conducted a screening for E. sinica strains on the basis of total alkaloids content [ephedrine (E) + pseudoephedrine (PE)] and selected strains having no less than 0.7% total alkaloids content as defined by the Japanese Pharmacopoeia 18th edition. Strains having characteristic E or PE content were uncovered: E-rich strains had 100% E content and PE-rich strains had 99% PE content. We were able to select E. sinica strains on the basis of two factors: high rooting rate of cuttings and high or characteristic alkaloid content. These strains are valuable for breeding.