감자절간 기내배양에서 소괴경의 형성과 형태적 발달

Abstract

One-node stem pieces　ca. 1 cm in length containing a axillary bud and a fully　expanded leaf were obtained from in vitro plants of potato (Solanum tuberosum L.). Leaves　were removed and the nodes were cultured on the MS medium to investigate the effects of temperature, day length, sucrose, and CCC in microtuber formation and development. The fresh weight of microtubers after 80 days increased significantly at 8% sucrose and 20℃ compared with 28℃. The tuberization and develpment were reduced at 28℃ except short-day treatment of 8 hours at 8% sucrose. The fresh weight　and diameter were increased on the culture medium added CCC 500 mg/L. The potato tuberization was promoted under short daylength, and it showed great effect by treatment with the CCC. Though the tuberization was promoted at low temperature of 20℃ in a histologic change of an axillary bud part cell of a potato, the cells were able to observe the swelling growth. Swelling growth of tissue was stimulated in the darkness and was more remarkable by addition of CCC. In particular, in the visual ratio of cell division for each position in the tissue, the cortex part showed larger ratio of cell expansion than that of the pith part. The effect of CCC was identified at 8% sucrose in the darkness. The effect of CCC was not showed in sucrose 3% under long daylength of 16 hours. As a result, the fact of a substance with AGPase important for starch composition was certified by the result with the increse of AGPase activity on high concentration of sucrose, CCC, and dark treatment by which tuber formation and development are promoted.