• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1744-1749
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• 2010

The role of endophytic fungi in plant growth and development is well documented. However, endophytic fungi with growth promotion capacity have never been isolated from weeds previously. In the current study, we isolated 8 fungal endophytes from the roots of Monochoria vaginalis, a serious weed of rice paddy in Korea. These isolates were screened on Waito-C, in order to identify plant growth promoting metabolites. Two fungal isolates (M5.A & M1.5) significantly promoted the plant height and shoot length of Waito-C during preliminary screening experiments. The culture filtrates (CFs) of M5.A and M1.5 also promoted the shoot length of Echinocloa crusgalli. Gibberellins (GAs) analysis of the CFs of M5.A and M1.5 showed that these endophytic fungi secrete higher quantities of GAs as compared with wild-type G. fujikuroi KCCM12329. The CF of M5.A contained bioactive GAs ($GA_3$, 2.8 ng/ml; $GA_4$, 2.6 ng/ml, and $GA_7$, 6.68 ng/ml) in conjunction with physiologically inactive $GA_9$ (1.61 ng/ml) and $GA_{24}$ (0.18 ng/ml). The CF of M1.5 contained physiologically active GAs ($GA_3$, 1.64 ng/ml; $GA_4$, 1.37 ng/ml and $GA_7$, 6.29 ng/ml) in conjunction with physiologically inactive $GA_9$ (3.44 ng/ml), $GA_{12}$ (0.3 ng/ml), and $GA_{24}$ (0.59 ng/ml). M5.A and M1.5 were identified as new strains of Penicillium sp. and Aspergillus sp., respectively, based on their 18S rDNA sequence homology and phylogenetic analysis.

• 한국약용작물학회지
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• 제15권5호
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• pp.315-318
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• 2007

An effective rapid propagation method was established through in vitro cultures of the medicinal plant, Cudrania tricuspidata. In vitro plantlets were obtained from in vitro germinated seeds. The various levels of cytokinins (BAP, Kinetin and TDZ) were tested on multiple shoot formation from plantlets. BAP (1.0 mg/l) treatment induced highest number of multiple shoots. Single shoot cultures gave higher initial shoot numbers than 5 shoots per culture. Among the various culture media, the shoot elongation was optimal on 2 MS basal medium without growth regulators. The IAA (2.0 mg/l) treatment induced highest number of roots. IBA (2.0 mg/l) treatment more promoted in vitro root growth than other concentrations. Rooted shoots were transferred directly to small pots with an artificial soil and successfully acclimatized.

• Journal of Plant Biotechnology
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• 제50권
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• pp.183-189
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• 2023

This study investigated the impact of two distinct MS basal media: one containing FeNaEDTA and the other FeEDDHA, on the growth of five unique gerbera cultivars (Shy Pink, Pink Holic, Breeze, Harmony, Snow Dream). Notably, the response to these media types varied significantly among the cultivars, particularly concerning leaf yellowing and plant growth. 'Shiny Pink' and 'Pink Holic' exhibited leaf yellowing on the FeNaEDTA-containing medium but displayed leaf greening on the FeEDDHA-containing medium. In contrast, 'Snow Dream,' 'Harmony,' and 'Breeze' remained unaffected on both medium types. However, the FeNaEDTA-containing medium promoted higher plant height and petiole length in 'Breeze,' 'Harmony,' and 'Snow Dream' than the FeNaEDTA-containing medium did. A promotive effect of silver nanoparticles (AgNPs) on plant growth and leaf greening was observed in 'Pink Holic,' particularly on the FeNaEDTA-containing medium, while the addition of AgNPs to the FeEDDHA-containing medium negatively affected plant growth. These results highlight the substantial influence of medium type, specifically the presence of FeNaEDTA or FeEDDHA, on gerbera growth responses, emphasizing the critical role of medium selection in gerbera propagation. Additionally, when contemplating the addition of AgNPs for in vitro gerbera propagation, it is crucial to consider the medium type.

• Journal of Plant Biology
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• 제33권1호
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• pp.41-48
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• 1990

Changes in polamine titers during shoot differentiation in Cymbidium sp. (Jungfrau) protocorms were studied in order to investigate the mechanism of shoot differentiation by using auxin-inhibitors(PCIB, TIBA), hormones(GA3, ABA, BA), and phenolic compounds (2,4-dichlorophenol, catechol). The shoot differentiation and propagation of protocorms were promoted by PCIB or 2,4-dichlorophenol, and the growth of differentiated shoot were promoted by TIBA or catechol. In BA-treated protocorms, white or brown protocorms were observed. Putrescine was the most abundant polyamine during the propagation and differentiation processes. As compared with putrescine, spermidine did not show significant changes and spermine was not detected at all. Putrescine titers decreased after a temporary increase, and then again increased in the presence of GA3, ABA, 2,4-dichlorophenol, and then again increased in the presence of GA3, ABA, 2,4-dichlorophenol, catechol, or PCIB. But, in BA-treated protocorms, putrescine level was much lower than spermidine.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.327-330
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• 2002

A plant growth-promoting substance, FM001, was isolated from the culture broth of Acremonium strictum MJN1. The purification steps included solvent extraction, adsorption chromatography using Diaion HP20, TLC on silica, and HLPC using a C-18 column. The purified FM001 enhanced rice seedling growth by $11.1\%\;and\;34.0\%$ of the dried weight of the shoots and roots, and also radish growth by $26.5\%\;and\;23.7\%$ of the top length and dried weight. FM001 also significantly promoted the growth of red pepper by increasing $32.7\%$ of fruit weight and $11.3\%$ as regards the height. FM001 consisted of C, H, O, N, and S, and its molecular weight was determined to be 537.78 Da. The structure of FM001 resembled brassinosteriods, and it would appear to have great potential as an effective bio-fertilizer.

• Journal of Plant Biotechnology
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• 제4권2호
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• pp.83-89
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• 2002

To establish in vitro mass production system of grape anthocyanin pigments through callus and cell suspension culture, the effects of nitrogen amount and the ratio of $NO_3^-$/$NH_4^+$ in the medium on cell growth and anthocyanin production were investigated. Total nitrogen amount and the ratio of $NO_3^-$/$NH_4^+$ in the medium strongly affected anthocyanin production and cell growth. When $NH_4^+$ was fixed, the cell growth was promoted by 50 mM total nitrogen (20 mM $NO_3^-$ : 30 mM $NH_4^+$ ) than other nitrogen combinations, and was strongly inhibited when $NO_3^-$ was lacking (0 mM $NO_3^-$ : 60 mM $NH_4^+$ ) while anthocyanin production was increased. When $NO_3^-$ was fixed, the cell growth was promoted by 70 mM total nitrogen (40 mM $NO_3^-$ : 30 mM $NH_4^+$) than other nitrogen combinations, and was strongly inhibited when $NO_3^-$ was lacking (0 mM $NO_3^-$ : 60 mM $NH_4^+$ ) while anthocyanin production was increased. Cell growth was gradually increased by all nitrogen combinations, but anthocyanin production reached its peak on day 4 in culture. Anthocyanin content increased with decreasing cell density. Sucrose was rapidly hydrolyzed to fructose and glucose within 4 days. Glucose and fructose concentrations in the medium increased and peaked at the 4th day. The anthocyanin content of $NH_4^+$-free 2% sucrose media was 2 times (200 $\mu\textrm{g}$/g) higher than that of 1% sucrose. When $NO_3^-$ was lacking, the highest anthocyanin production was observed at 4% sucrose after 12 days of culture, and increased along with the sucrose concentration.

• 한국토양비료학회지
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• 제44권1호
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• pp.112-117
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• 2011

A strain of phosphate solubilizing bacterium was isolated from rhizosphere and identified as Burkholderia sp. by 16S-rRNA gene sequence analyses. The bacterium was found to release gluconic acid and the solubilization of hydroxyapatite in the liquid medium by a significant drop in pH to 3.7 from an initial pH 7.0. The soluble-P concentration continuously increased during the incubation periods and the total amount of soluble P released in culture filtrate was detected at 990 mg $L^{-1}$ after 10 days of inoculation. Most promoted maize growth was found in the standard NPK (240-120-120 kg $ha^{-1}$) soil inoculation with Burkholderia sp. (Twenty milliliters/plant, 106 CFU) and also in the absence of Burkholderia sp. inoculation, the soil amended with only 2/3 levels of P gave significant higher plant yield compared to 1/3 levels of P or without P supplementation.

• Journal of Plant Biology
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• 제35권4호
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• pp.425-429
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• 1992

Ranunculus sceleratus 엽병의 세포 신장은 에틸렌에 의하여 촉진되는 것으로 알려져 있다. 오옥신을 처리한 엽병조직 절편에서 spermine은 세포 신장과 에틸렌의 생성을 비슷한 양상으로 억제하였다. Spermine 농도에 대한 오옥신 유도 에틸렌 생성 억제반응은 ACC에 의한 에틸렌 생성의 경우도 유사한 양상을 나타내었으며 이는 폴리아민이 ACC가 에틸렌으로 전환되는 과정을 억제한다는 것을 시사한다. 오옥신 유도 에틸렌 생성은 폴리아민 생합성 억제제인 DFMA아 DFMO에 의하여 각각 현저하게 촉진되었으며 DFMA에 의한 에틸렌 생성의 증가는 spermine을 고농도로 처리하므로써 완전히 소멸되는 결과를 얻었다. 이러한 결과들은 오옥신과 에틸렌에 대한 Ranunculus의 세포성장 반응에서 내생 폴리아민이 조절 역할을 수행한다는 가능성을 입증하는 것이다.

• The Plant Pathology Journal
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• 제37권3호
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• pp.307-314
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• 2021

Pepper (Capsicum annuum L.) is an important agricultural crop worldwide. Recently, Colletotrichum scovillei, a member of the C. acutatum species complex, was reported to be the dominant pathogen causing pepper anthracnose disease in South Korea. In the present study, we isolated bacterial strains from rhizosphere soil in a pepper field in Gangwon Province, Korea, and assessed their antifungal ability against C. scovillei strain KC05. Among these strains, a strain named BS1 significantly inhibited mycelial growth, appressorium formation, and disease development of C. scovillei. By combined sequence analysis using 16S rRNA and partial gyrA sequences, strain BS1 was identified as Bacillus velezensis, a member of the B. subtilis species complex. BS1 produced hydrolytic enzymes (cellulase and protease) and iron-chelating siderophores. It also promoted chili pepper (cv. Nockwang) seedling growth compared with untreated plants. The study concluded that B. velezensis BS1 has good potential as a biocontrol agent of anthracnose disease in chili pepper caused by C. scovillei.

• 원예과학기술지
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• 제35권4호
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• pp.439-445
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• 2017

Transplant production in a plant factory with artificial lighting provides several benefits; (1) rapid and uniform transplant production, (2) high production rate per unit area, and (3) production of disease free transplants production. To improve the growth of runner plants when strawberry transplants are produced in a plant factory, we conducted two experiments to investigate (1) the effect of different light intensity for stock and runner plants on the growth of runner plants, and (2) the effect of different container volume for runner plants on their growth. When the stock and runner plants were grown under nine different light conditions composed of three different light intensities (100, 200, and $400{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPF) for each stock and runner plants, increasing the light intensity for stock plants promoted the growth of runner plants, however, the growth of runner plants was not enhanced by increasing the light intensity for runner plants under same light intensity condition for stock plants. We also cultivated runner plants using plug trays with four different container volumes (21, 34, 73, and 150 mL) for 20 days after placing the stock plants, and found that using plug trays with lager container volume did not enhance the growth of runner plants. These results indicate that providing optimal condition for stock plants, rather than the runner plants, is more important for increasing the growth of the runner plants and that the efficiency of strawberry transplant production in a plant factory can be improved by decreasing light intensity or container volume for runner plants.