• Journal of Applied Biological Chemistry
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• 제48권1호
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• pp.11-15
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• 2005

Salinity of soils in greenhouse has been increased by massive application of fertilizers. Nitrogen fertilizer was most popular, and thus nitrate became the majority of soil salinity. Accumulation of nitrate led to deleterious effects on the growth and development of crops and vegetables. Microbial strains able to utilize nitrate and thus remove excess nitrate from farm land soils were isolated from 15 different soils of greenhouses and plastic film houses. Four strains able to grow in medium containing 50 mM $KNO_3$ were isolated, among which only E0461 showed high capacity of nitrate uptake. Nitrate uptake by E0461 was dependent on culture medium and was increased by addition of tryptone and peptone. Although E0461 was able to grow without tryptone and peptone, growth was slow, and no nitrate uptake was observed. Nitrate appeared to facilitate E0461 growth in the presence of tryptone and peptone. Through kinetic analysis, nitrate uptake was measured at various concentrations of nitrate, and half-life was calculated. Nitrate concentration decreased with increasing incubation period, and plot between half-lives and initial concentrations of nitrate fitted to single exponential function. These results suggest one major factor plays an important role in microbial nitrate uptake.

• 한국농공학회논문집
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• 제52권3호
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• pp.47-55
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• 2010

Investigations on the inundation damage and improvement measures were carried out centering around the protected horticultural complex concentrated in lowlands on the side of Geum river, in Nonsan and Buyeo, Chungnam. Most greenhouses were single-span plastic houses in this area, and tomato, strawberry and watermelon were cultivated mainly. 45.8 % of whole farmhouse were experienced in damage by inundation, and a frequency of the damage was average once in 11 years. The most urgent problem at the greenhouse culture in this area was showed in order of drainage improvement, irrigation water resources and energy saving. Consideration items in drainage improvement project for protected horticulture were showed in order of extending drain pumps, extending drain canals, using concrete flume in drain ditch. It needs to consider systematic plans that can restrain new establishment of greenhouses on the lowland paddy field in drainage area. It is difficult to remove greenhouses which are already established or prohibit cultivation. Therefore we should impose minimum duty items so that greenhouse tillers can cope with inundation. And it is thought that managing agency need to minimize farmers damage by improving drainage ability and introducing maintenance pattern that is different from rice cropping.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.50-61
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• 1994

Biological control of important fungal diseases such as Phytophthora blight of red pepper, gary mold rot of vegetables, and powdery mildew of many crops was attempted using an antagonistic bacterium, Bacillus sp. AC-1 in greenhouses and fields. The antagonistic bacterium isolated from the rhizosphere soils of healthy red pepper plant was very effective in the inhibition of mycelial growth of plant pathogenic fungi in vitro including Phytophthora capsici, Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Valsa mali, Fusarium oxysporum, Pythium ultimum, Alternari mali, Helminthosporium oryzae, and Colletotrichum gloeosporioides. Culture filtrate of antagonistic Bacillus sp. AC-1 applied to pot soils infested with Phytophthora capsici suppressed the disease occurrence better than metalaxyl application did until 37 days after treatment in greenhouse tests. Treatments of the bacterial suspension on red pepper plants also reduced the incidence of Phytophthora blight in greenhouse tests. In farmers' commercial production fields, however, the controlling efficacy of the antagonistic bacteria was variable depending on field locations. Gray mold rot of chinese chives and lettuce caused by Botrytis cinerea was also controlled effectively in field tests by the application of Bacillus sp. AC-1 with control values of 79.7% and 72.8%, respectively. Spraying of the bacterial suspension inhibited development of powdery mildew of many crops such as cucumber, tobacco, melon, and rose effectively in greenhouse and field tests. The control efficacy of the bacterial suspension was almost same as that of Fenarimol used as a chemical standard. Further experiments for developing a commercial product from the antagonistic bacteria and for elucidating antagonistic mechanism against plant pathogenic fungi are in progress.

• 식물조직배양학회지
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• 제24권2호
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• pp.87-91
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• 1997

제초제 저항성 유전자를 코팅시킨 입자를 particle bombardment 기법으로 자주감자 품종의 인공씨감자에 도입시켰다. 발아직전에 있는 인공씨감자의 생장점 부위를 집중적으로 particle bombardment 한 후 발아한 인공씨감자를 온실에 심었다. 온실에서 5주동안 생육시킨 후 northern 분석결과 유전자가 발현된 2개의 형질전환체를 선발하였고 제초제 살포 실험을 한 결과 형질전환 되지않은 식물체는 모두 고사하였지만 형질전환된 2개의 자주감자 식물체는 생존하였다.

• 한국육종학회지
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• 제40권3호
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• pp.211-214
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• 2008

Haploid system by anther culture allows the development of homozygous lines when doubled. The response of anther culture to Basta (glufosinate) resistance was investigated on transgenic plants (cv. Anjungbyeo) in order to identify inheritance of bar gene associated with Basta. Most of the regenerated transgenic plants were sterile, and only a few plants produced viable seeds ($A_1$) in the greenhouse. The bar gene was analysis by PCR in basta resistant transgenic plant ($TA_0$). The transgenic seeds ($A_1$) were significantly germinated in Basta solution compared with non-transformed seeds. As a result of anther culture, in regenerated haploid plants, segregation ratio was 1:1 in five of eight cross combinations. In diploid plants, segregation ratio was 1:1 in seven of eight cross combinations. Although there was some differences in the cross combinations, most of the combinations had 1:1 segregation ratio which supports the theory. The difference may be a result of the small sample size or the difference of anther culture response caused by genotypic difference. Hence, when many cross combinations were anther-cultured the results would support the theory.

• 한국자원식물학회지
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• 제28권3호
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• pp.363-369
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• 2015

Sweet potato has low regeneration capacity, which is a serious obstacle for the fruitful production of transgenic plants. Simple and rapid regeneration method from storage root explants of purple sweet potato (Ipomoea batatas L.) was investigated. The embryogenic callus was observed from 4 cultivars and its highest rate was induced at 1 μM 2,4-D after 5 weeks of culture. Result revealed that a low concentration of 2,4-D and low light intensity was important factors for embryogenic callus formation. After subculture on medium with 5 μM ABA for 4 days, subsequently, occurred the regeneration of shoots within 4 weeks when these embryogenic callus was transferred onto the MS hormone free medium. Regenerated shoots were developed into platelets, and grown normal plants in the greenhouse. We developed a simple and quickly protocol to regenerate plantlets in storage root explants of purple sweet potato. This regeneration system will facilitate tissue culture and gene transfer research of purple sweet potato.

• The Plant Pathology Journal
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• 제15권3호
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• pp.152-157
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• 1999

An antibiotic compound was isolated from the culture of an antagonist against Fusarium oxysporum f. sp. sesami, Bacillus polymyxa strain KB-8, and tested for the control of Fusarium wilt of sesame in greenhouse conditions. Optimum conditions for culturing the antagonist to obtain the maximum antibiotic activity were determined using different culture media, initial medium acidity, and incubation periods for which yeast -malt extract agar with the initial acidity of pH 5 and over 13 days culture were best. Antibiotic substances extracted by methanol had 2 main fractions, KB-8A and KB-8B, in thin layer chromatography (OLC) with Rf values of 0.35 and 0.67 in a solvent system of chloroform : methanol = 7 : 3. The fraction KB-8A wa purified further by XAD-2, silica gel and Sephadex LH-20 column chromatography, and crystalization. Its minimum inhibitory concentrations (MICs) were $12.8\mu\textrm{g}$/ml for F. oxysporum and Alternaria mali, $6.4\mu\textrm{g}$/ml for Colletotrichum gloeosporioides and Rhizoctonia solani, and $3.2\mu\textrm{g}$/ml for Phytophthora capsici. Soil drenching of antibiotic KB-8A in the concentrations of $13.0\mu\textrm{g}$/ml and $26.0\mu\textrm{g}$/ml effectively inhibited the Fusarium wilt of sesame in a greenhouse test, which appeared to be comparable to the fungicide benlate of $6.5\mu\textrm{g}$ a. i./ml.

• 식물조직배양학회지
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• 제22권6호
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• pp.335-337
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• 1995

주목의 줄기절간 조직배양에 의한 다경줄기 유도를 위해 식물생장조절물질 중 4가지 형태의 싸이토키닌 효과를 조사 한 바, BAP, kinetin 및 thidiazuron의 경우 거의 반응을 보이지 않았으나, zeatin을 5 $\times$ $10^{-5}$M 처리하였을 경우 평균 6 개 이상의 다경줄기를 얻을 수 있었으며, 배양시료에 따라서 는 12개 이상의 다경을 형성하는 경우도 관찰되었다. 유도된 다경줄기를 지속적으로 계대배양하여 줄기를 신장시킨 후 이로부터 2 cm 크기의 기내삽목도 가능하였다. 기내발근율은 LP기본배지를 이용하는 것이 비교적 양호하였으나 효율은 3%에 지나지 않았다. 기외발근의 경우, 약 34%까지 발근율을 올릴 수 있었으며 포지에 이식시킨 조직배양묘는 1년이상 정상적인 생육을 보이고 있음이 관찰되었다.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.88-94
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• 2005

Plant tissue culture studies have been done for the preservation of medicinal plant resources and efficient production of pharmaceutically important secondary metabolites. Micropropagation methods for Cephaelis ipecacuanha have been established and these methods enabled much more efficient propagation of the plants than the conventional methods using seedling or layering. The C. ipecacuanha plants derived from tissue culture grew uniformly in the field and they showed higher alkaloid contents compared to the plants grown from seedlings. Hairy root cultures of C. ipecacuanha and Panax ginseng have been established by infection with Agrobacterium rhizogenes, and the production of important pharmaceuticals by these cultures have been successfully demonstrated. In the case of C. ipecacuanha, the highest alkaloid yields from the hairy roots cultured for 8 weeks were 2.75-fold cephaeline (5.5 mg) and one third emetine (0.7 mg) compared with those from the roots of one-year old plant propagated through shoot-tip culture and cultivated in a greenhouse (2.0 mg cephaeline and 2.0 mg emetine). In the case of P. ginseng, ginsenoside contents in the hairy roots optimally cultured for 4 weeks were much higher than those in the roots of 4-year old field-grown plant. Thus our medicinal plant tissue cultures demonstrate desirable properties. However, they are always exposed to danger of microbial contamination or unexpected trouble of culture facilities. Cryopreservation of plant tissue cultures is a reliable method for long-term preservation. Cryopreservation studies on these cultures are also presented.

• 원예과학기술지
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• 제19권4호
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• pp.488-494
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• 2001

95-98년에 걸쳐 대구지방에서 '여홍'을 공시하여 육묘하고 9월 중순 24cm 플라스틱 포트에 정식하여 노지재배 관리하였다. 9월 하순부터 다음해 1월 말까지 5일 간격으로 전조온실에 딸기를 입실재배하면서 휴면최심기, 반휴면 상태의 초형을 나타내는 보온개시기, 노지포장의 초상온도 측정치로부터 '여홍'의 휴면 타파 경과 시기, 저온적산시간의 기점, 생육 및 수량에 관한 조사 결과는 다음과 같다. 대구지방에서 '여홍'의 휴면이 가장 깊은 시기는 95년에는 11월 5일, 96년에는 10월 25일, 97년에는 10월 31일이였다. '여홍'이 전조온실에서 반휴면 상태의 초형을 나타낸 보온개시기는 95년도와 96년에는 11월 10일-20일, 97년에는 11월 10일-30일이었다. 휴면최심기를 기점으로 '여홍'의 휴면타파에 요하는 초상기온 $5^{\circ}C$ 이하 100-200시간의 경과시기는 96년에는 11월 16일-25일, 97년에는 11월 24일-12월 5일이었다. '여홍'의 수량은 각 연도마다 10월-11월의 보온개시에서 좋은 결과를 나타내었다. '여홍'은 전조 재배 시 촉성작형의 적응특성을 나타내었고 전조반촉성 재배 시에는 휴면최심기 기점 $5^{\circ}C$ 이하 50-150시간 경과 시에 보온 개시하는 것이 최선이라 사료되었다.