IN VITRO MASS-PROPAGATION OF CHINESE ARTICHOKE (STACHYS SIEBOLDII MIQ.)

In vitro mass-propagation of Chinese artichoke (Stachys sieboldii Miq.) was conducted. The shoot tips were cultured in the medium which consists of Murashige-Skoog (MS) major salts and FeEDTA, Ringe and Nitsch vitamins and microelements, 2% sucrose and 0.8% agar at pH 5.6. N⁶-benzylaminopurin (BA)(0.1 mg 1^-1) was supplemented. The multiple shoots were formed by the growth of axillary shoots about 1 month after culture. They were then logitudinally separated into a few clumps. If the explant grew to a single shoot without branching, the shoot was transversely sectioned into upper half and lower half. The shoot clupms or the half shoot-sections were cultured in the same medium. Again, multiple shoots were formed. In the similar manner, total 5 times of the shoot separation/sectioning were conducted at 25 day intervals. Total 1067 shoots were obtained from 11 initial explants after 4 month culture period. Roots were easily formed from the shoots in the hormone free basal medium or 0.1 mg 1^-1 3-indolebutyric acid (IBA) supplemented MS medium. The rooted plantlets were successfully acclimatized in the soil condition. Thus, this in vitro multiplication method was by far rapid compared to conventinal tuber separation.