• Journal of the Korean Society of Tobacco Science
• /
• v.13 no.1
• /
• pp.43-52
• /
• 1991

These studies were carred out to obtain the transformant from tobacco cells by Agrobacterium spp. from crown gall and soil at the natural field in Korea, and identified their virulence. Kodo's and Clark's selective media were used for isolation of Agrobacterium spp. In these media, total of 99 strains were characterized based on the morphological characteristics of colonies. Among them 34 strains were able to induce on carrot discs. And hypervirulent strains C23-1 and K29-1 were identified as Agrobacterium tumefaciens biotype 1 and biotype 2, respectively. These strains formed fast growing, larger gall as compared to those induced by other strains on the carrot discs. Transformed tobacco callus was initiated on the phytohormone free MS medium with 250$\mu\textrm{g}$/ml carbenicillin after co-cultivation of tobacco stem explants and Agrobacteria. On the phytohormone free media, shoot was rarely formed from transformed callus. However, these shoot were teratoma shoots which were not grown as normal shoot, and teratoma shoot from transformant by C23-1 was smaller than that of K29-1.

• Korean Journal of Agricultural Science
• /
• v.38 no.2
• /
• pp.213-217
• /
• 2011

Agrobacterium rhizogenes, a gram-negative soil bacterium, is one of the most widely studied among them. A, rhizogenes can transfer T-DNA, excised from Ri (root inducing)-plasmids from the bacterial to the plant cell. It is the causal agent of 'hairy root' diseases in plants, and has been used for the production of hairy root cultures from a multitude of species. Five different strains of Agrobacterium rhizogenes differed in their ability to induce Scutellaria baicalensis hairy roots and also showed varying effects on the growth in hairy root cultures. A. rhizogenes R 1000 is the most effective strain for the induction (57.3%) and growth (11.9 g $L^{-1}$) in hairy root of Scutellaria baicalensis. Our results demonstrate that use of suitable strains of A. rhizogenes may allow study of the regulation of flavone biosynthesis in hairy root cultures of Scutellaria baicalensis.

• Korean Journal of Microbiology
• /
• v.4 no.2
• /
• pp.1-4
• /
• 1966

As a part of studies of plant tumor induction, this experiment was prepared for the purpose of studying the ability of tumor induction and the tendency of tumor initiation in some Korean plants using the various Agrobacterium tumefaciens strains. Results obtained from this experiment are as follows. The virulences of five strains used in this experiment were gradually decreased in order of strain A6Kl, B6, 11BV7, T37 and 11 BNV6. Especially strain T37 which is known to the host limited strain showed virulent effect to the most of plants given for the materials as well as strain A6Kl, B 6 and 11BV7. Concerning the grade of tumor development, in plants which has tough stem, for example, Glycine max Meer, tumor induction was not well developed after the inoculation of all strains. Particullary in Ricinus communes Linne all strains showed virulent effect but tumor tissues were declined in relation to the development of lignification. It was also confirmed that the induction of tumor tissues on plants is to delay according to the increase of the age of host plants.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.120.2-120
• /
• 2003

Agrobacterium vitis is a causal agent of crown-gall disease on grapevine. In Korea, grapevine variety (GeoBong) have severely been infected by the bacteria since stems of the variety were buried in soil for overwintering. Infection ratio over 70-80％ was observed on 7 years old GeoBong grapevine in Ansung and Cheonan. PCR specific primers for A. vitis strains were designed using nucleotide sequences of vir A gene in Ti-Plasmid, pheA gene in chromosomal DNA and a URP-PCR polymorphic band. Three hundred bacterial strains were isolated from the different 80 galls formed on GeoBong grapevine in Cheonan and Ansung of Korea and were screened to identify A. vitis using the three specific PCR primers for Agrobacterium vitis. Twenty-four bacterial strains that are detected by the primers were further confirmed by pathogenicity and biochemical methods. To investigate the genomic diversity of the bacterial strains, twenty primers of 20 mer referred to universal rice primers (URP) were applied for PCR fingerprinting, Of them, URP2R and URP2F primers could effectively be used to detect polymorphism within the bacterial strains.

• Research in Plant Disease
• /
• v.13 no.3
• /
• pp.137-144
• /
• 2007

Fifty nine strains of Agrobacterium vitis, the causal agent of crown-gall disease on grapevine, originating from different geographical regions and 16 grapevine cultivars including 35 Kyoho cultivar of Korea, were characterized by PCR polymorphic analysis using Universal Rice Primer(URP). Of 12 URP primers, primers URP1F, URP2R, URP2F, and URP4R, URP17R were available for detecting PCR polymorphic bands among the A. vitis strains. PCR polymorphic bands produced by primers URP2F and URP17R were profiled to 12 strain types. A. vitis strains originated from Kyoho cultivar of grapevine showed relatively simple genetic diversify of the four PCR types, while the A. vitis strains originated from other grapevine cultivars and type culture strains showed various genetic diversity with 8 types. Unweighted Pair-Group Method with Arithmetic mean(UPGMA) cluster analysis using the URP-PCR polymorphic bands showed 59.4. vitis strains are genetically clustered into large seven groups.

• Journal of Plant Biology
• /
• v.39 no.3
• /
• pp.179-184
• /
• 1996

The purpose of this study is to obtain the most efficient combination of Agrobacterium tumefaciens strains and Ti plasmids for the construction of dicotyledonous plant vector system. Ti plasmid-curing A. tumefaciens A136 and KU12C3 were transformed with four kinds of Ti plasmids, pTiBo542, pTiA6, pTiKU12 and pTiAch5, respectively. The stems of 28 species of dicotyledonous plants were then inoculated with these transformants and examined for crown gall formation. The different combination of A. tumefaciens strains and Ti plasmids showed quite a difference in terms of the crown gall formation. Agrobacterium strins A136 and KU12C3 have a same plant host range in case that both strains harour the same kind of Ti plasmid, pTiBo542 or pTiAch5. However, the above-mentioned both strains have quite different host range in the event of containing the same Ti plasmid, pTiKU12 or pTiA6. In case that KU12C3 contains pTiA6 or pTiKU12, this strain has a wider plant host range than A136. The plant host range of pTiBo542 is the widest, followed by pTiA6, pTiKU12 and pTiAch5. Twelve plants among 28 tested plants are not transformed by any virulent Agrobacterium strains used in this study. In conclusion, A. tumefaciens KU12C3 and A136 harboring pTiBo542 showed the widest host range for transforming dicotyledonous plants. Also, it was acertained that the host range of Ti plasmids is affected by chromosomal level.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.5
• /
• pp.415-418
• /
• 2004

The effects of sonication and vacuum infiltration on transformation efficiency was investigated by using immature embryos of Korean wheat as explants. Two Agrobacterium tumefaciens strains, KYRT1 and EHA105, carrying pCAMBIA 1305.1 were used. Transformation efficiency was demonstrated by the detection of $\beta-glucu-ronidase$ (GUS) activity. GUS expression showed clear difference among Korean wheat cultivars. Geurumil showed higher GUS expression efficiency $79.1\%$ compared with other cultivars. The effects of the duration of vacuum infiltration and sonication treatment showed a tendency high GUS expression efficiency by their combination. In comparison with other Agrobacterium strains, KYRT1 showed high efficiency in most Korean cultivars.

• Journal of Plant Biotechnology
• /
• v.32 no.3
• /
• pp.161-165
• /
• 2005

Agrobacterium tumefaciens-mediated cotyledonary explants transformation was used to produce transgenic cucumber. Cotyledonary explants of cucumber (c.v., Eunchim) were co-cultivated with strains Agrobaderium (LBA4404, GV3101, EHA101) containing the binary vector (pPTN289) carrying with CaMV 355 promoter-gus gene as reporter and NOS promoter-bar gene conferring resistance to glufosinate (herbicide Basta) as selectable marker. There was a significant difference in the transformation frequency depending Agrobacterium strains. The EHA101 of bacterial strains employed gave the maximum frequency (0.35%) for cucumber transformation. Histochemical gus and leaf painting assay showed that 15 individual lines were transgenic with the gus and bar gene. Southern blot analysis also revealed that the gus gene was successfully integrated into each genome of transgenic cucumber.

• Journal of Plant Biotechnology
• /
• v.31 no.4
• /
• pp.255-259
• /
• 2004

Agrobacterium tumefaciens-mediated cotyledonary node transformation was used to produce transgenic soybean. Cotyledonary node explants of three cultivars and one genotype were co-cultivated with strains Agrobacterium (LBA4404, GV3101, EHA101, C58) containing the binary vectors (pCAMBIA3301 and pPTN289) carrying with CaMV 35S promoter-GUS gene as reporter gene and NOS promoter-bar gene conferring resistance to glufosinate (herbicide Basta) as selectable marker. There was a significant difference in the transformation frequency depend on bacteria strain. The EHA101 strain of the bacterial strains employed gave the maximum efficiency (3.6%). One hundred-six lines transformed showed the resistance in glufosinate. Histochemical GUS assay showed that at least 11 plants transformed with the GUS gene were positive response. The soybean transformants were obtained from the Thorne (5 plants), 1049 (5 plants) and Bakun (1 plant), respectively. Southern blot analysis and leaf painting assay revealed that the GUS and bar gene segregated and expressed in their progeny.

• Molecules and Cells
• /
• v.39 no.9
• /
• pp.705-713
• /
• 2016

The efficiency of Agrobacterium-mediated transformation in plants depends on the virulence of Agrobacterium strains, the plant tissue culture conditions, and the susceptibility of host plants. Understanding the molecular interactions between Agrobacterium and host plant cells is crucial when manipulating the susceptibility of recalcitrant crop plants and protecting orchard trees from crown gall disease. It was discovered that Arabidopsis voltage-dependent anion channel 1 (atvdac1) mutant has drastic effects on Agrobacterium-mediated tumorigenesis and growth developmental phenotypes, and that these effects are dependent on a Ws-0 genetic background. Genetic complementation of Arabidopsis vdac1 mutants and yeast porin1-deficient strain with members of the AtVDAC gene family revealed that AtVDAC1 is required for Agrobacterium-mediated transformation, and there is weak functional redundancy between AtVDAC1 and AtVDAC3, which is independent of porin activity. Furthermore, atvdac1 mutants were deficient in transient and stable transformation by Agrobacterium, suggesting that AtVDAC1 is involved in the early stages of Agrobacterium infection prior to transferred-DNA (T-DNA) integration. Transgenic plants overexpressing AtVDAC1 not only complemented the phenotypes of the atvdac1 mutant, but also showed high efficiency of transient T-DNA gene expression; however, the efficiency of stable transformation was not affected. Moreover, the effect of phytohormone treatment on competence to Agrobacterium was compromised in atvdac1 mutants. These data indicate that AtVDAC1 regulates the competence of Arabidopsis to Agrobacterium infection.