To improve the transformation efficiency by Agrobacterium tumefaciens mediation in indica rice, we used calli derived from immature and mature embryo. Calli formed from immature embryos produced more transgenic plants than those from mature embryos. The m

Transgenic plants from hypocotyl segments of buckwheat were produced with the Agrobacterium strain LBA4404 harboring the binary vector pBI121 containing chimeric genes of neomycin phosphotransferase II (npt II) and β -glucuronidase (gus). Two weeks after co-cultivation with Agrobacterium, most of the hypocotyl segments gradually became brown and died on the selection medium containing 100mg/~ell of kanamycin. Plants regenerated from the hypocotyl explants grown on selection medium were GUS-positive in the leaf, stem and vascular tissues by histochemical assay, and varied in gus activity (440-2568 pmol, 4-MU/mg protein) by fluorimetry. The plants showing GUS activity were confirmed of containing GUS and NPT-II genes by polymerase chain reaction (PCR). Within 3 months, transgenic buckwheat plants were able to obtained from the hypocotyl segments.

현삼의 기내배양에서 낮은 농도의 2,4-D(0.01, 0.1mg/l) 와 TDZ(0.01, 0.1, 2.0mg/l)이 조합처리시 shoot 분화가 좋았으나, 2,4-D의 농도가 높아질수록 TDZ과 조합처리시 shoot 분화가 저조 하였다. 형질전환 확인을 위한 PCR 분석에서 선발표지 유전자로 사용되는 NPT II gene의 확인하였는데 형질전환되지 않은 식물체에서는 나타나지 않는 DNA 절편이 형질전환 식물체에서 나타났으며 kanamycin 50 mg/ l 첨가된 배지에서 선발된 식물체에서 NPT II gene(700bp)이 plant genome 안으로 삽입되었음을 확인하였다. 형질전환 식물체의 항균활성 검정에서는 Asperigillus awamori에 대해 대조구 식물체와 같이 항균성이 없는 것으로 나타났으나 항바이러스성 단백질인 PAP가 도입된 식물체에서는 IC50의 값이 Asperigillus awamori에 대해서 각각 320 μg/ml 과 300μg/ml, C. herbarum에 대해서도 IC50 값이 80μg/ml, 100μg/ml로 높은 항균성을 나타내었다. 형질전환 식물체와 형질전환되지 않은 식물체를 대상으로 SDS-PAGE를 수행하여 본 결과 감염된 형질전환되지 않은 잎과 감염되지 않은 잎에서는 나타나지 않는 30kDa의 분자량을 가지는 새로운 band가 PAP유전자에 의하여 형질전환된 식물체에서 각각 확인되었다. Asperigillus awamori의 경우에 PAP 형질전환체의 단백질을 첨가한 경우 모두 포자가 발아가 억제 되었고 균사생장이 지연되었으며 균사가 생장되더라도 포자와 생장하는 균사가 투명하여졌으며 생장하는 균사의 굵기도 가늘어지는 특성을 나타내었다. 병원균 접종 후 생육조사에 의하면 형질전환 식물체가 초장과 지상부, 지하부의 생체 중에서 모두 형질전환 되지 않은 식물체보다 다소 높게 나타났다. Fusarium에 의한 전형적인 병징인 뿌리썩음 병과 유관속 시들음 증상이 형질전환 되지 않은 식물체에서 병징의 scale은 3.2와 3.0으로 나타나는 반면 형질전환된 식물체에서는 2.0과 2.5으로 비교적 낮게 나타났다.

Transgenic Petunia hybrida cv. Rosanpion was produced by Agrobactepium tumefaciens LBA4404 harboring a binary vector pBI 121 containing β-glucuronidase (gus) and neomycin phosphotransferase (nptII). For genetic transformation, leaf discs were precultured on MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L BA (MNB) for 2 days and cocultured for 15 mins with A. tumefaciens. For selection of transformant, leaf discs were transferred to fresh MNB containing 50 mg/L kanamycin and 500 mg/L cefotaxime. Eighteen plants were regenerated and four were confirmed by PCR for detection of gus and nptII gene integrated into the nuclear genome of petunia ‘Rosanpion’. Using this transformation system, we expect that transgenic petunia ‘Rosanpion’ incorporating a useful gene can be produced.

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.

This experiment was conducted to introduce phosphinothricin acetyl -transferase(PAT) gene, resistant to basta and non-selective herbidide, into tobacco(Nicotiana tabacum cv.BY4). For shoot formation,tobacco leaf disks were placed on the MS medium supplemented with 2.0mg/L BA and 0.1mg/L NAA. In this medium condition, tobacco leaf disces were cocultivated with A. tumefaciens MP90 containing NPT IIand PAT resistant to kanamycin and Basta, respectively. Shoots were obtained in the medium containing antibiotics, and those were transferred to rooting medium supplemented with 0.1mg/L NAA and antibiotics. The plants obtaining roots were transplanted into soil. Phenotype of transgenic tobacco plant was mostly as normal plant. However, about 5% was abnormal plant, which did not set seeds. PCR analysis and southern blot were performed to determine transformation. As the results, it was confirmed that PAT gene was stably integrated into tobacco genome.When herbicide, basta, was sprayed to the plants confirmed by PCR, the transgenic plants showed normal growth, whereas normal plants died. Therefore, the result of this experiment show that tobacco transformation for the resistance to basta, non-selective herbicide, was successful because PAT gene was stably integrated into tobacco.