A Study was conducted to investigate comparison of in vitro tuberization between normal and transgenic potato plantlets harboring adenosine deaminase gene in potato cultivar of Desiree. In time course study of in vitro tuberization, the rate of tuberization in four lines were increased till 6 weeks. but maintained stil after 7 weeks. Microtuber initiation of transgenic lines, 43 and 39 were faster than other lines, but no difference was observed after 5 weeks compared with normal plantlets. In all transgenic lines, the majoirty of microtubers produced were small(less than 100 mg) and medium(100-200mg) size rather than large size(more than 200 mg). Among 4 lines , line 9 produced the highest number of microtubers per each culture vessel. The results of this experiment suggest that there is no significant difference in microtuber production efficiency between normal and transgenic potatoes.

This study was carried out to obtain the information for growth characteristics of crown gall tumor and hairy root transformed by Agrobacterium spp,. on the media with phytohormones, casein hydrolysate and activated charoal. Crown gall tumors and hairly roots were formed respectively on potato tuber discs infected by tumerfaciens A ch 5 and A.rhizogenes ATCC15834. These tumors and roots could be grown on the phytohormone free media. PCR analysis of Rol C and Vir C gene fragments confirmed that crown gall root was prompted on the medium containing 2,4-D 2mg/l with casein hydrolysate lg/l. The survival ration of crown gall tumor callus derived from potato increased on medium containing the activated charcoal 0.5∼0.2mg/l because of the prevention, on the other hand, hairly roots were necrosis on the same medium. Callus derived from hairly root were excellently grown for a short time by suspension culture on liquid medium containing 2.4-d 2mg/L and casein hydrolysate lg/l.