• The Korean Journal of Ecology
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• 제15권3호
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• pp.297-309
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• 1992

The growth of digitaria adscendens and eleusine indica, annual weeds common in japan, was experimentally analyzed under varying untrient conditions. compared with e. indica, d. adscendensshowed a higher the two under high nitrogen availability. Higher net assimilation rate(nar) in d. adscendens than e. india was responsible for high RGR in D. adscendens under the low nitrogen availability. The different of NAR in the two species was induced not by leaf nitrogen content but by nitrogen use efficiency. Under unfertilized conditions nitrogen uptake rate(nur) was greater in d. adscendens than e. indica. Specific absorption rate in two species was similar, but root mass was greater in d. adscendens than e. indica.d. adscendens allocated more dry matter to roots than e. india earlier stage of seedlings. The contributed to higher rot mass and in turn resulted in higher nur in d. adscendens than that in e. india. It is concluuded that the larger allocation of dry matter to roots at early seedling stage in d. adscendens plays an important role in obtaining nitrogen for the continuation of growth under low nitrogen availability.

• Journal of Ginseng Research
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• 제4권2호
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• pp.186-193
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• 1980

The causal organism of Phytophthora disease on Panax ginseng Meyer in Korea was isolated and identified as Phytophthora cactorum. It's pathogenicity, etiology, and possible control measures were investigated. Disease symptoms on various parts of ginseng plants were also described The fungus caused seedling and mature plant blight and root rot. Oospores were easily formed on potato dextrose agar and corn meal agar. Oospores, however, were not formed in the diseased root tissues but did in the in footed shoots such as leaves, petioles, and stems and in the inoculated berries.

• 미생물학회지
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• 제12권2호
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• pp.94-98
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• 1974

This study was conducted from April 1 to September 31, 1973. Ten strains of Fusarium spp. were isolated from the diseased ginseng in two local areas at Kangwha-Gun nad Kumsan-Gun in Korea. Among of them, 2 strains ($G_1$, $G_4$) did not have virulence to ginseng in reinoculation. Their cultural, morphological characteristic and hose virulence to pea seedling were examined. Taxonomical identification of 8 isolates followed by the method of Wollenweber, Snyder nad Toussoun, Booth, Matuo and Snyder. All of eight strains were identified as the Fusarium solani f.sp.pisi(Jones) Synd. et Hans.

• 생물환경조절학회지
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• 제9권3호
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• pp.146-150
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• 2000

본 시험은 단고추 자루식 양액재배시 육묘일수에 따른 생육, 수량에 미치는 영향을 구명하고자 풋트당 2주로 하여 육묘일수 20일, 30일, 40일, 50일, 60일 처리구를 두고 재배를 요약하면 다음과 같다. 묘 소질은 육묘일수가 길수록 묘 생육이 좋았고 정식후 개화일 빨랐으나 평균 개화소요일수는 30일묘에서 48일로 가장 짧았고 다음으로 20일묘 순이었다. 뿌리활력은 20일과 30일묘에서 양호하였고 1차측근수는 30일묘가 1.5mm 이하 굵기의 뿌리수가 106.5개로 가장 많았으며 1차 측근장도 1,085cm로 가장 길었다. 정식후 생육은 엽중, 그중,경중 모두 30일묘에서 좋았으며, 수량은 수확초기에는 육묘일수가 긴 60일과 50일묘에서 수량이 많았으나 재배기간이 길어질수록 30일과 40일묘에서 수확량이 많았고 총수량도 많았다.

• The Plant Pathology Journal
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• 제20권1호
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• pp.63-66
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• 2004

Ginseng (Panax ginseng) is one of the most widely cultivated medicinal herbs in Korea. However, yield losses reached up to 30-60％ due to various diseases during 3 or 5 years of ginseng cultivation in the country. Therefore, successful production of ginseng roots depends primarily on the control of diseases. The objective of this study was to select potential biocontrol agents from rhizobacteria isolated from various plant internal root tissues for the control of multiple ginseng diseases as an alternative to fungicides. Among 106 Bacillus strains, two promising biocontrol agents, Bacillus pumilus strain B1141 and Paenibacillus lentimobus strain B1146, were selected by screening against root rot of ginseng caused by Cylindrocarpon destructans in a greenhouse. Pre-inoculation of selected isolates to seed or l-year-old root of ginseng resulted in stimulation of shoot and/or root growth of seedlings, and successfully controlled root rot caused by C. destructans (P<0.05). Furthermore, drenching of cell suspension of the selected isolates on seedling-growing pots reduced the incidence of Phytophthora blight after the seedlings were challenged with zoospores of Phytophthora cactorum (P<0.05). P. lentimorbus strain B1146 showed antifungal activity against various soil-borne pathogens in vitro, while B. pumilus strain B1141 did not show any. Results of this study suggest that some rhizobacteria can induce resistance against various plant diseases on ginseng.

• Current Research on Agriculture and Life Sciences
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• 제17권
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• pp.7-13
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• 1999

고추의 뿌리에 서식하고 있는 근권미생물을 30여종 분리하여 고추 검은 곰팡이병원균 A. alteranta에 길항하는 미생물을 분리한 결과 분리주 No. J-24 균주가 가장 길항력이 우수하였으며 Bacillus subtilis로 동정되었다. B. subtilis J-24는 검은곰팡이병균(Alternaria alternata)에 대해서는 생육저지 효과가 99%로 나타났으며, 그외 갯빛곰팡이병균(Botrytis cinerea), 역병균(Phytophthora capsici), 잘록병균(Pythium ultimum), 탄저병균(Colletotrichum gloeosporioides), 겹무늬병균(Stemphylium botryosum)에도 생육저지효과를 강하게 나타내었다. 고추 유묘의 생장활력은 미생물제제가 첨가된 상토가 일반 상토 보다 엽면적이 15%, 줄기길이가 12%, 뿌리길이가 12% 증가하였고 전체 건물중이 약 13% 증가하여 고추유묘의 생장활력이 증가되었다.

• 한국응용곤충학회지
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• 제20권4호
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• pp.183-190
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• 1981

작물시험장, 충남농촌진흥원 및 일반농가에서 수집한 40개 참깨종자표본의 종자전염진균을 Blotter 법으로 조사하였던 바 Alternaria sesami, A. sesamicola, A. tenuis, A. longissima, Cercospora sesami, Cephalosporium sp., Corynespora cassiicola, Fusarium equiseti, F. moniliforme, F. oxysporum, F. semitectum, Macrophomina phoseolina 그리고 Myrothecium roridum이 검출되었다. 그 중 A. sesami, A. sesamicola, A. tenuis, C. cassiicola가 많은 비율로 검출되었다. 참깨 종자내의 감염부위를 알아본 결과, C. cassiicola가 가장 깊숙이 배에까지 감염되어 있었으며 Chlorine으로 종자표면소독을 하였을 경우에도 완전히 제거되지 않았다. 이균에 이병된 종자를 살균토양에 파종하였을 경우 심한 발아저해와 유묘고사를 초래하였다. C. cassiicola의 종자상에서의 생육상과 배양기상에서의 배양적성질 및 포자의 형태를 기술하였다. 병원성을 조사하기 위하여 배양균의 포자현탁액을 참깨에 분무접종한 결과, C. cassiicola는 참깨의 잎과 줄기에 또는 자색의 병반을 나타내며 이것이 급격히 확대되어 고사하였다. A. sesami, A. sesamicola, A. longissima, C. sesami도 참깨 잎에 반점 또는 blight의 병징을 나타내었으나, A. tenuis은 병원성이 없었다. 토양접종실험의 결과, F. oxysporum과 M. phaseolina는 강한 병원성을 나타내어 심한 종자부패와 유묘고사를 초래하였다.

• The Plant Pathology Journal
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• 제34권5호
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• pp.393-402
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• 2018

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

• 한국작물학회지
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• 제37권1호
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• pp.59-67
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• 1992

벼 기계이앙을 위한 어린모 육묘에 이앙 가능한 최단기 육묘일수와 맷트형성기간을 구명하기 위하여 육묘온도와 깔판재료를 달리하여 그 효과를 조사하였던 바 다음과 같은 결과를 얻었다. 1. 육모온도가 높을수록, 또 육묘기간이 길어질수록 어린모의 맷트형성이 양호하였으며, Metalaxyl(25% 수화제, 1,000 배액) 종자침종처리는 무처리에 비하여 맷트형성 기간이 단축되었다. 2. Metalaxyl 침종처리는 무처리에 비하여 어린모의 초장신장 효과가 있었고, 경엽중과 근중도 무거웠으며, 입고병과 뜸묘의 발생을 방지하였다. 3. 어린모의 맷트형성 촉진 보조재로서 흡수지깔판(키친타올 1컵)의 효과가 인정되었으며, ＆apos;Metalaxyl 침종＋비닐＋흡수지＆apos;처리는 다른 처리에 비하여 맷트형성 기간을 1～2일 단축시켰다. 4. 어린모의 최소 육묘일수는 파종 후 5일이였다. 육묘조건은 종자를 Metalaxyl 1,000배액에 24시간 침종한 후 비닐＋흡수지 깔판에 파종하여 30/2$0^{\circ}C$(획 / 야) 온도에서 육묘한다. 5. 일반농가 비닐하우스에서 어린모 육묘시(중부지방)에는 5월의 하우스내 온도를 야간 11～16$^{\circ}C$, 획간 28～32$^{\circ}C$ 정도로 볼 때, 산파상자를 사용할 경우에는 ＆apos;Metalaxyl 침종＋비닐깔판＆apos;처리로, 또 어린모 전용 육묘상자를 사용할 경우에는 ＆apos;Metalaxyl 침종＆apos;처리로 육묘하면 파종 후 6일에 안전 이앙이 가능한 것으로 판단된다.

• 한국약용작물학회지
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• 제26권5호
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• pp.345-353
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• 2018

Background: Some phenolics detected in the soil may inhibit the seed germination and seedling growth of ginseng (Panax ginseng). This study investigated the effect of irrigation and ginseng root residue addition on the soil microbial community and root rot disease in 2-year-old ginseng. Methods and Results: Each $20{\ell}$ pot was filled with soil infected with ginseng root rot pathogens, and irrigated daily with $2{\ell}$ of water for one month. After the irrigation treatment, ginseng fine root powder was mixed with the irrigated soil at a rate of 20 g per pot. In descending order, ${NO_3}^-$, electric conductivity (EC), exchangeable Na (Ex. Na) and K (Ex. K) decreased due to irrigation. In descending order, ${NO_3}^-$, EC, Ex. K, and available $P_2O_5$ increased with the additon of ginseng powder to the soil. The abundance of Trichoderma crassum decreased with irrigation, but increased again with the incorporation of ginseng powder. The abundance of Haematonectria haematococca increased with irrigation, but decreased with the incorporation of ginseng powder. The abundance of Cylindrocarpon spp. and Fusarium spp., which cause ginseng root rot, increased with the incorporation of ginseng powder. The abundance of Arthrobacter oryzae and Streptomyces lavendulae increased with irrigation. The abundance of Streptomyces lavendulae decreased, and that of Arthrobacter spp. increased, with the incorporation of ginseng powder. Aerial growth of ginseng was promoted by irrigation, and ginseng root rot increased with the incorporation of ginseng powder. Conclusions: Ginseng root residues in the soil affected soil nutrients and microorganisms, and promoted ginseng root rot, but did not affect the aerial growth of ginseng.