ABSTRACT
INTRODUCTION Although Salvia, one of the most commercially important and widely cultivated medicinal plants, is a perennial, it does not last above three or four years without degenerating, so that plantations should be renewed at least every four years (Grieve, 1994). In addition, and in spite of the fact that considerable progress has been made in the field of the in vitro production of various secondary metabolites, such as rosmarinic acid and cryptotanshinone (see I. Hippolyte and Em. Panagiotopoulos, in this volume), the application of biotech nological methods for the propagation of these species is rather limited. This might be due to the fact that most Salvia species can be easily propagated by cut tings and layers, most frequently in the spring and in the autumn, by pulling off or pegging down shoots from threeyear-old plants (Grieve, 1994). Some species, like S. sclarea, the clary sage, are propagated by seed, but for most species this method of propagation is limited by the rather low seed germination rate.
