Clonal Propagation of Isoplexis canariensis*

Abstract

Isoplexis is a plant genus closely related to Digitalis. Members of this genus contain cardenolides considered more “primitive” than those present in Digitalis. Isoplexis plants, tissue cultures, and isolated cardenolides may thus be used to elucidate the biosynthesis of cardenolides in the Scrophulariaceae. Therefore, a method was developed to cultivate and propagate Isoplexis canariensis (L.) Lindl. ex. G. Don in vitro. Seeds were germinated in liquid modified MS medium and shoot cultures were established and propagated in liquid modified MS medium containing 0.1 mg/l IAA and 1 mg/l BAP. Shoot cultures were also established from excised axillary buds and propagated on solid culture medium containing 0.1 mg/l IAA and 1 mg/l BAP. Shoots of either origin were rooted in medium containing 1 to 5 mg/l IAA and 0.5 to 4 mg/l IBA. Rooted plantlets were cultivated for 2 to 3 weeks in hormone-free modified MS medium and then transferred to the greenhouse, where they developed into healthy plants.

Key words

Cardenolides - Isoplexis canariensis - Scrophulariaceae - micropropagation - shoot culture - rooting - Vermiculite