Atractylodes lancea autotetraploids induced by colchicine treatment of shoot cultures

Two strains of autotetraploid plants of Atractylodes lancea DC. (Compositae) were raised from the in vitro colchicine-treated shoot cultures, and field trials were performed to evaluate their growth and the amount of essential oil components in the rhizome in comparison with the corresponding diploids. The tetraploid plants had larger leaves than the diploids. One of the selected tetraploid lines had about 1.5 times as heavy rhizomes as the diploid and contained atractylodin, hinesol and beta-eudesmol in the rhizome to as great an extent or slightly less than the diploids. However, the contents of these constituents in the rhizome of the other tetraploid strain were lower than the diploids. The chloroplast number per guard cell, stomatal length, and stomatal density of leaf lower epidermis of the shoot cultures were good indicators for distinguishing tetraploids from diploids.