Morphological and Growth Characteristics of Tetraploid Polygonum multiflorum L. with Colchicine Treatment
Background : This study was performed to investigate the morphological and growth characteristics of tetraploid Polygonum multiflorum L. with colchicine treatment, and to clarify its effective induction and time for the increase of rhizome hypertrophy and effective components. Methods and Results : The induction of tetraploid P. multiflorum were done with colchicine treatment of 0.1, 0.5, and 1.0% conc. and the time was treated with 12, 24, and 48 hrs, respectively. DMSO 1% is treated for the effective penetration of colchicine with constant-temperature oven at 24C. Leaf explant was added the HR-A solution stained with HR-B solution, and then determined whether DNA contents of the doubles or not. Seed stand rate showed lower tendency as higher treatment concentration and as delayed the treatment time. When treated in DMSO 1% with 48 hr, seed stand was so small rate with 2%, and treated in 0.5% with 12 hr, seed stand was recorded higher rate with 33%. When treated in 0.5% colchicine with 24 hr, chimera and tetraploid induction rates were highest and obtained 29 individual chimera and 5 individual tetraploid. On overground growing, mean stem diameter of tetraploid (11.3 ㎜) is two times thicker than that of diploid (6.4 ㎜), with the vigorous growth. leaf length and width of tetraploid was 9.1 and 6.2 ㎝, respectively, and that of diploid was 6.8, and 5.1 ㎝, respectively. Stem diameter of a scape was also more thicker tendency in tetraploid than in diploid, chlorophyll contents over 29% existed in tetraploid. Investigated result from stoma no. and size of leaf with 400 magnification, stoma no. of diploid (26 individual) was four times higher than that of tetraploid (7 individuals), the size of tetraploid (38 ㎛) is twice longer in size of diploid (18 ㎛) and stoma area are broaden in four times. Seed length of tetraploid (3 ㎜) is longer than that of diploid (22 ㎜); but, seed width of tetraploid (22 ㎜) is widen than that of diploid (14 ㎜) in seed size comparison. That is, seed length is bigger in 1.4 times and seed width is bigger in 1.6 times, and seed surface area is broaden in two times. Conclusion : From above results, overground growing of tetraploid P. multiflorum is fairly better than that of native P. multiflorum. In the future, this tetraploid variety will promote to register when recognize the excellence than native species after tested the disease tolerance, underground growing characteristics, and key index component.