• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.129-134
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• 2001

Winter bud explants from 15 individual angelica tree (Aralia elata) were cultured in vitro to find out optimal conditions for somatic embryo induction as well as plant regeneration. Calli are induced and grown on MS medium supplemented with 1.0 mg/L 2,4-D for 4 weeks and subcultured on a half-strength MS medium without phytohormones to induce somatic embryos. Inter-simple sequence repeat (I-SSR) markers were analyzed with total DNAs extracted from the trees. Genotype effects on somatic embryo induction were examined by cluster analysis. Callus induction rate varied from 58.5 to 100% among the genotypes. Somatic embryo induction rate also greatly varied from 0 to 100% among the genotypes. There was a significant difference in somatic embryo induction rate even among the individual trees that showed close genetic relationships each other. This suggested that somatic embryo induction rate in Aralia elata be influenced by a few major specific genes rather than whole genomic similarity among individual trees. Four individuals of Ulneong-7, Cheju-1, Shingu and China, which are recalcitrant to somatic embryo induction, turned out to have a close genetic relationship, suggesting that both physiological and genetic factors affect somatic embryo induction. The results suggest that genotype selection be the most important factor to achieve an efficient propagation, although cultural optimization through medium and explant manipulation may also play crucial roles in somatic embryogensis as well as plant regeneration of these species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.356-360
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• 2005

Mature embryos were aseptically excised with a scalpel and sliced in fragments measuring 0.5 mm in diameter (sliced mature embryo fragment; 4 ${\~}$ 5 fragments/one embryo). Sliced mature embryo fragments of six wheat cultivars were cultured to develop an efficient method of callus induction and plant regeneration. Callus derived from sliced mature embryo fragments showed a good capacity to embryogenesis and regeneration. Furthermore sliced mature embryo fragments decreased contamination from fungi and bacteria. The high efficiency of callus induction were obtained Keumkangmil and Bob­white. For plant regeneration, selected embryogenic calli were transferred to two types regeneration media. An average number of green spots per callus was 4 to 5 in regeneration media after about one week. Percentage of plant regeneration showed high in regeneration medium containing 0.1 mg/l 2,4-D and 5 mg/l zeatin. Especially, Keumkangmil ($27.5\%$) and Bobwhite ($33.3\%$) showed high regeneration efficiency. This regeneration system from sliced mature embryo fragments may provide an effective and convenient explant for plant transformation studies.

• Journal of Plant Biotechnology
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• v.3 no.1
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• pp.19-25
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• 2001

Induction of somatic embryogenesis from Brazilian eggplant variety F-100 was studied in response to four auxin types. NAA, at the optimal concentration of 54 $\mu\textrm{m}$, was the only one that resulted in the induction of somatic embryos in either leaf and cotyledon explant and, at murk lower intensity and frequency, in hypocotyl and epicotyl explants. The optimal temperatures for embryo induction were 28 and 35$^{\circ}C$ for cotyledon and leaf explants. Incubation at 22$^{\circ}C$ caused a significant reduction both in the frequency and intensity of induction. This system was used to study the effects of position and orientation of the tissue on the culture medium as well as of antibiotics and explant co-cultivation with Agrobacterium on the efficiency of somatic embryo induction. The intensity of embryo induction was greater in the midsections of cotyledons relative to apical and basal regions, when the abaxial surface was in contact with the culture medium. The presence of antibiotics resulted in approximately 40-60% reduction of embryo induction relative to control explants, which originated 335$\pm$26.6 embryos. Co-cultivation with Agrobacterium before treatment with antibiotics caused a more drastic reduction (80-99%). Ampicilin treatment after cocultivalion with Agrobacterium caused the least inhibitory effect, allowing the production of 60 embryos/explant.

• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.71-76
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• 1999

Anthers of two hot pepper cultivars, Milyang-jare and Geryongsan-jare, were cultured on MS medium containing 0.1 mg/L 2,4-D and 0.1 mg/L kinetin. The influence of pretreatment at 4$^{\circ}C$ and 32$^{\circ}C$ on induction of microspore embryo was investigated. Milyang-jare was superior to the Geryongsan-jare in microspore embryo induction. The 32$^{\circ}C$ pretreatment increased embryo induction compared to the 4$^{\circ}C$ pretreatment while the 4$^{\circ}C$ pretreatment stimulated callus induction. Microspore embryos were regenerated to plantlets in the same medium or hormone free medium at 32$^{\circ}C$ treatment but most embryos failed to develop directly into plantlets at 4$^{\circ}C$ treatment. The optimal period of the 32$^{\circ}C$ pretreatment was 3 days in Milyang-jare and 6 days in Geryongsan-jare. The 32$^{\circ}C$ pretreatment was essential for induction and growth of microspore embryo in pepper.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.349-353
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• 2004

Mature embryo and leaf base segment of Korean oat were used as materials in an experiment to check plant regeneration efficiency. MS media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin, and picloram were used for callus induction from mature embryos and leaf base segments. Three mg/l of 2,4­D and 3 mg/l of picloram in callus induction medium showed high frequency for plant regeneration from mature embryos. Leaf base segments were transferred to callus induction medium and incubated at $25^{\circ}C$ in 16/8 hr light/dark cycle for 3 weeks. Callus induction from leaf base segments of Malgwiri showed high efficiency in medium containing 3 mg/l of 2,4-D and 1 mg/l of kinetin $(91.8\%)$. In case of Samhangwiri, the combinations of phytohormones did not show significant difference. Regeneration from leaf base segments showed high frequency in shoot medium containing 1 mg/l of antiauxin, tri-iodobenzoic acid (TIBA) and 1 mg/l of 6-benzyladenine (BA). Calli induced from leaf base segments of Samhangwiri and Malgwiri in media containing 3 mg/l of 2,4-D and 3 mg/l of picloram showed high regeneration frequency. It appears that the callus initiation medium may be an important factor for subsequent plant regeneration.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.388-395
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• 2015

Somatic embryogenesis is as an excellent technology for potential use in plant mass production, germplasm conservation, or genetic engineering. We examined the effect of cold storage using 3 embryogenic callus lines with different levels of embryogenesis competence derived from immature zygotic embryo cultures of Kalopanax setemlobus. Somatic embryo induction, germination and plant conversion were evaluated after 1, 3 and 6 months storage at $4^{\circ}C$ in the dark. Most cold-stored embryogenic calli formed somatic embryos normally even after 6 months; however, the induction rate was gradually decreased by increasing the storage period. The most competent line tended to show a slight decline in somatic embryo induction rate, as compared with other lines after cold storage. In general, cold storage resulted in reduced somatic embryo germination and plant regeneration, although 93% somatic embryo germination and 91% plant conversion were achieved regardless of the storage period. Cold storage led to cell browning and degradation. Additionally, the cell structures were confirmed by the aceto-carmine and evans blue dye evaluation. Collectively, our results showed that embryogenic callus of K. septemlobus could be preserved at $4^{\circ}C$ without subculture for 6 months, and suggested the need for storage of relatively more competent embryogenic calli lines to support somatic embryo induction.

• Journal of Plant Biotechnology
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• v.6 no.1
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• pp.45-50
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• 2004

Somatic embryos were induced from immature cotyledons and cultured on a MS medium containing 40mg/L 2,4-D. The maximum induction of embryos was obtained from immature cotyledons in a size of 3-4mm, and the highest frequency was obtained in the induction medium at pH 7.0. For embryo development, embryogenic tissues were transferred to a MSM6AC and MSM6 media. Developing embryos were placed at 27$^{\circ}C$with dim light (20$\mu$$molm^{-2}$$s^{-1}$) provided by cool fluorescent tubes (3-D wavelength light is better than standard light). Somatic embryos were clearly developed from globular stage to cotyledonary stages. The color of embryo may be a useful parameter for estimation of embryo quality. When the embryo becomes mature, embryo will be ready for desiccation in order to induce roots and shoots of embryos.

• Journal of Plant Biology
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• v.14 no.1
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• pp.1-4
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• 1971

To determine the amylase fromation mechanism and the effect of GA. in germinating barley seeds, they were divided into embryo-less seed, isolated embryo, aleurone layer and pure endosperm etc., treated with GA, and cultured separately or in mixed lots. The result obtained are as follows. 1) The amylase of barley seed is formed in the aleurone layer under the effect of inducing materials excreted from the embryo. 2) The embryonic materials amylase formation could be substituted for by GA. Therefore it can be presumed that the substance produced by the embryo which induces amylase synthesis is probably GA or material similar to it.

• Journal of Embryo Transfer
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• v.1 no.1
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• pp.69-75
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• 1986

These studies were carried out to investigate the induction of superovulation, the synchroniration and the effect of the number of embryos transferred, the developmentai stage of embryos and the donor-recipient synchrony on pregnancy rate in cattle. The results obtained in these studies were as follows: 1. The number of oorpus leuteum(CL) and the embryos reoovered were higher in FSH treated animals than in PMSG treated (9.4 vs 8.1 and 6.1 vs 4.5) and showed the same trend in recovery rate (64.9% vs 55.6%). 2. Two shots of cioprostenol at 11 days showed significantly high no. of animals in estrus in order of crossbred, Holstein and Korean native cattle. No significant differencies were noted in the seoond shots groups. And the interval to estrus and response were shorter and better in second shot group than that in first shot group. 3. The pregnancy rate when additional one embryo was transferred after Al at estrus (52.8%) was higher than the group transferred one (32.8%) or two (36.9%) embryos. 4. The pregnancy rate of embryo in morula stage was better than that in blasto cyst stage (39.3% vs 32.5%). 5. The pregnancy rate in the recipients exhibited estrus later than the donor (66.7%) was the higher than those exhibited estrus (40.3%) or exhibited estrus before the donor (37.5%).

• Journal of Embryo Transfer
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• v.14 no.2
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• pp.89-92
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• 1999

효율적인 homozygous 동물을 생산하기 위한 실험의 단계로 염색체가 4배체인 수정란의 이용성을 타진하기 위해 생쥐 수정란과 cytochalasin B를 사용하여 4배체 유도에 관한실험을 수행하였다. 생쥐 2-세포기 수정란을 10$\mu\textrm{g}$/ml 농도의 cytochasin B로 약 20시간 배양하였을 때 모든 수정란은 발육을 거의 멈추었으나, 이 수정란을 cytochalasin B-free medium에 체외배양하였을 때 발육이 재개되어 48시간 후 상실기나 배반포기까지 약 74%의 발육율을 나타내었다. 그러나 발육된 수정란의 세포수는 대조구에 비해 휠신 적은 것으로 나타났다. 염색체 분석결과 cytochalasin B로 처리한 대부분의 수정란은 4배체인 것으로 나타났고 약간의 수정란은 mosaicism과 다배체를 나타내기도 하였다. 그러므로 cytochalasin B를 이용하여 효과적으로 4배체의 수정란을 유도할 수 있는 것으로 나타났다.