Development of a Micropropagation Protocol for St. John's Wort (Hypericum perforatum L. )

Hypericum perforatum L. (St. John's Wort) has an extensive history as an important medicinal herb used for the treatment of neurological and depressive disorders (Linde et al., 1996). The objective of this study was to establish an in vitro tissue culture protocol for St. John's Wort. Nodal segments, axillary buds, and leaf disc explants produced multiple shoots and callus on Murashige and Skoog minimal organics medium supplemented with combinations of indoleacetic acid (IAA; 0.57, 2.85, 5.71 µM) and benzylaminopurine (BA; 2.22, 4.44, 8.88 µM). Shoot production occurred on all combina- tions of IAA/BA tested and was significantly less in treatments without hormones. Callus production was higher on treatments containing 2.85 µM IAA + 4.44 µM BA, or 5.71 µM IAA + 8.88 µM BA. Shoots transferred to hormone-free medium at 8 weeks formed roots by 12 weeks. A micropropagation protocol was established for St. John's Wort using mature plants as the explant source.