• 한국산림과학회지
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• 제86권4호
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• pp.430-434
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• 1997

희귀 수종인 산개나리(3년생)의 산초지 액아를 배양하여 식물체를 유도하였다. 효과적인 증식법 구명을 위해 MS 배지에서 세 가지 싸이토키닌(BAP, kinetin, zeatin)의 농도별 효과를 조사하였다. 증식은 식물 생장조절 물질이나 농도별 효과가 뚜렷하지 않았으나 zeatin 처리시 줄기 및 잎의 발달에 효과가 있었다. kinetin 처리는 줄기 생장과 더불어 모두 발근되는 특징을 보였고, BAP와 zeatin은 발근은 가능하나 고농도로 갈수록 발근율이 감소하였다. 황화처리는 줄기의 생장을 촉진하였다. 줄기는 3년 이상의 계대배양 후에도 정상적인 증식이 가능했다. 발근된 식물체는 인공 배양토에서 100% 활착되었으며 산지에 이식하여 정상 생장하였다. 이상의 결과는 희귀 수종인 산개나리의 기내 번식으로 자생지의 복원이 가능함을 시사한다.

• 한국작물학회지
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• 제44권4호
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• pp.316-320
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• 1999

Nine accessions of red rices collected from different regions were tested for germination characteristics in relation to seed maturity and several storage conditions after harvest. No red rice seeds germinated at five days after anthesis (DAA). Wanjuaengmi (long-grain red rice) seeds at 10DAA germinated up to 30% of total samples, producing only abnormal seedlings, whereas 10D-AA-seeds of normal cultivar showed only 3.3% germinability. Some red rice seeds absorbed more water than cultivated varieties, and showed less decrease in germination rate than cultivated varieties when seeds were exposed at -1, -5 or -1$0^{\circ}C$ for up to 60 hours after soaking. Red rice accessions maintained more than 95% germination when stored. indoor for 120 days. Two short-grain red rices showed about 50% germination when overwintered in the field, while other long-grain red rices and cultivated rices germinated less than 10%. Germination of seeds overwintered in clay loam soil was lower than that in loam soil, and seeds on surface germinated less than those in 1~7cm depth.

• The Plant Pathology Journal
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• 제22권1호
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• pp.11-15
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• 2006

Five seed samples of carrot were tested to detect Alternaria spp. by blotter method. A. alternata and A. radicina were detected from all the seed samples as high as $25.8-70.5\%$ and $37.5-63.5\%$, respectively. A. dauci was detected from four seed samples as low as $0.5-7.5\%$. The three Alternaria spp. were detected from the pericarp and the seed coat and endosperm of the carrot seeds but not from the embryo by component plating test. A. alternata and A. radicina were much more detected from the pericarp than the seed coat and endosperm. A. dauci was detected from the pericarp and the seed coat and endosperm at similar rate. The seed sample which was most severely infected with A. radicina showed the lowest rate of germination in the test on top of paper (TP). In the TP test, differences in total infection rate of A. radicina and A. dauci of the seed samples were very closely correlated with those in incidence of seedling rot on the seed samples. However, there was no correlation between infection rate of A. alternata and rate of germination or seedling rot of the seed samples. Soil test for seedling growth revealed that there was no correlation between differences in total infection rate of A. radicina and A. dauci and those in rate of normal seedlings of the seed samples.

• 한국작물학회지
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• 제44권2호
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• pp.134-137
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• 1999

An experiment was carried out to determine the effects of priming and growth regulator treatment of seeds on the emergence and seedling growth of rice, Oryza sativa L. (cv. 'Ilpumbyeo'). Normal seeds were primed in a -0.6 MPa polyethylene glycol solution at 15$^{\circ}C$ for four days with air-bubbling. Then both primed and non-primed seeds were soaked in water, 100 ppm GA$_3$, 2 ppm ABA, and 10 ppm kinetin solutions for 24 hours. The seeds were planted in soil at 3 and 5 cm depths and allowed to germinate in a growth cabinet at 2$0^{\circ}C$. Generally, the emergence rate at the 3 cm seeding depth was higher and emerged faster compared with the 5 cm seeding depth. The emergence rate of primed seeds was higher and emerged faster compared to non-primed seeds. GA$_3$ and kinetin treatments were the most effective to improve the emergence rate of non-primed seeds. Coleoptile length at the 5 cm seeding depth was longer than that at the 3 cm seeding depth. Leaf number, plant height, and root length of primed seedlings were higher compared with non-primed seeds. GA$_3$ promoted the elongation of plant height and mesocotyle length.

• Plant Biotechnology Reports
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• 제4권4호
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• pp.243-251
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• 2010

Nitric oxide (NO) has been shown to be involved in diverse physiological processes in microbes, animals and plants. In this study, the involvement of NO in the development and possible roles in oxidative stress protection of Chinese cabbage (Brassica rapa subsp. pekinensis cv. Samrack-ulgari) seedlings were investigated. Exogenous application of sodium nitroprusside (SNP) retarded root elongation, while increasing lateral root formation of Chinese cabbage. Plants showed no signs of external stress due to SNP application in true leaves. Cotyledons of 3-week-old Chinese cabbage plants were found to be highly sensitive to SNP application. Treated cotyledons displayed rapid tissue collapse and associated cell death. Although SNP application reduced root growth under normal growth conditions, it also enhanced methyl viologen (MV)-mediated oxidative stress tolerance. Analysis of SNP application to Chinese cabbage leaf disks, revealed SNP-induced tolerance against oxidative stresses by MV and $H_2O_2$, and evidence includes prevention of chlorophyll loss, superoxide anion (${O_2}^-$) accumulation and lipid peroxidation. This report supports a role for nitric oxide in modulating early seedling development, programmed cell death and stress tolerance in Chinese cabbage.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.938-945
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• 2018

Salinity stress is an important environmental problem that adversely affects crop production by reducing plant growth. The impacts of rhizobacterial strains to alleviate salinity stress on the germination of Lactuca sativa and Raphanus sativus seeds were assessed using different concentrations of NaCl. Plant growth-promoting rhizobacteria (PGPR) strains were also examined to improve the early germination of Chinese cabbage seeds under normal conditions. Lactobacillus sp. and P. putida inoculation showed higher radicle lengths compared with non-inoculated radish (Raphanus sativus) seeds. LAP mix inoculation increased the radicle length of lettuce (Lactuca sativa) seedlings by 2.0 and 0.5 cm at salinity stress of 50 and 100 mM NaCl concentration, respectively. Inoculation by Azotobacter chroococcum significantly increased the plumule and radicle lengths of germinated seeds compared with non-inoculated control. A. chroococcum increased the radicle length relative to the uninoculated seeds by 4.0, 1.0, and 1.5 cm at 50, 100, and 150 mM NaCl concentration, respectively. LAP mix inoculation significantly improved the radicle length in germinated radish seeds by 7.5, 1.3, 1.2, and 0.6 cm under salinity stress of 50, 100, 150, and 200 mM NaCl concentration, respectively. These results of this study showed that PGPR could be helpful to mitigate the salinity stress of different plants at the time of germination.

• 한국자원식물학회지
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• 제11권1호
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• pp.30-39
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• 1998

Carrot seedling emgryos showing variations in cotyledon number were selected and anatomical comparisons of the embryo vascular systems were performed between the variants and normal two cotyledonary (5) embryos from 800 seedings germinated . Externally, all of the four and six cotyledonary embryos had two cotyledonary petioles. Each of the cotyledonary petioles divided into two or three on the upper part fo the petiole which result in four and six cotyledons, respectively. However, the embryos had three different cotyledonary petioles in the three cotyledonary embryos. On the basis of the pattern of vascular system, the four and six cotyledonary embryos had the same basic vascular system as fnormal two cotyledonary embryos, Therefore the cotyledon number abnormality could result from the branching split of the abnormally thickened upper part of the cotyledonary petiole. However, the three cotyledonaryembryos had a different vascular system from the normla two cotyledonary embryos. They could be regarded as different varieties form the two cotyledon embryos. All embryos observed had short cylindrical plumule sheath which formed by the fusion of the cotyledon bases. The presence of plumule sheath strontgly implied that the initiation of the cotyledons was not from the two localized primordia but from the circular proimordiu formed at the blobular stageof embryo, and it is not consistent with current views of cotyledon initiation. On the formation of the primary vascular system of carrot seedlings, it is suggested that the primary vascular system of the plumule was formed independently from that of the root-hypocotyle-cotyledon system.

• 한국작물학회지
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• 제55권2호
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• pp.126-132
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• 2010

천립중이 가벼워 수량은 낮으나 sucrose와 glucose함량이 상대적으로 높아 환자의 이유식 등의 사용을 목적으로 개발된 단미 벼 종자의 발아 및 출아특성과 기계이앙 상자육묘시 적정 파종량을 구명하기 위한 시험결과는 다음과 같다. 1. 단미의 비중별 분포비율은 1.0이하로 가벼운 종자가 97.4%로 대부분이었고 1.12이상인 충실한 종자비율은 2.0% 이하로 낮았다. 반면 일미벼는 단미와 달리 1.12이상 충실한 종자의 비율이 82.3%로 가장 높았고 1.0이하의 충실하지 못한 종자의 비율은 6.4%로 낮았다. 2. 비중별 발아율은 단미의 경우 88-91%로 비중에 관계없이 비슷하였으나 일미벼의 발아율은 단미와 달리 1.0이하는 24%, 1.0～1.12는 61～66%, 1.12이상은 93%로 종자 비중이 무거울수록 발아율이 높았다. 3. 발아속도도 단미 및 일미벼 모두 발아율과 비슷한 경향을 나타냈으나 비중이 1.12이상일 경우 일미벼의 발아속도는 단미보다 빨랐다. 4. 육묘를 위한 단미의 침종기간은 침종온도에 관계없이 일미벼보다 2～4일 더 길었다. 5. 단미는 일미벼에 비해 정상모의 비율이 낮고 비정상모의 비율이 높았는데 비정상모중에서 출아불량이 4.9%, 출아후 shoot의 생육정지는 4.7%, 출아후 생육불량모는 5.3%로 높았다. 6. 기계이앙 육묘시 단미의 적정 파종량은 관행 일미벼 어린모 및 중묘의 상자당 성묘개체수를 기준으로 볼때 관행과 같이 어린모는 220g, 중묘는 130g이었고 부피로는 육묘일수에 관계없이 관행 일미벼의 1.5배량이었다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.25-25
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• 2014

Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

• Journal of Ginseng Research
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• 제40권4호
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.