• The Plant Pathology Journal
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• 제28권1호
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• pp.55-59
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• 2012

Northern stem canker caused by $Diaporthe$ $phaseolorum$ var. $caulivora$ ($Dpc$) has become a serious disease in soybean. The objectives of this study were to survey the existence of $Dpc$ on soybean in Korea, and to examine the potential pathogenicity of $Dpc$ in seed decay. One such isolate, SSLP-4, isolated from a field-grown plant of the Korean soybean cultivar Danbaekkong, was identified as $Dpc$, based on its morphological and molecular characteristics by sequences of internal transcribed spacer (ITS), translation elongation factor (TEF) 1-${\alpha}$ and ${\beta}$-tubulin regions, as well as pathogenic analyses. Moreover, morphological and molecular analyses revealed that isolate SSLP-4 was nearly identical to $Dpc$ strains from the United States. Pathogenicity tests on hypocotyls of soybean seedlings and detached leaves resulted in typical symptoms of soybean northern stem canker and inoculation on plants at R5-R7 stage caused seed decay. All results suggest that the $Dpc$ strain SSLP-4 can cause both stem canker and seed decay on soybean. Thus, the SSLP-4 isolate has the potential to contribute greatly to understanding of host plant resistance mechanisms, both at vegetative and reproductive growth stages in soybean.

• Mycobiology
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• 제51권6호
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• pp.463-467
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• 2023

Soybean is one of the world's most widely cultivated food crops, and soybean seeds are supplied from national seed resources in Korea. However, the transmission of seed-borne diseases through infected soybean seeds is problematic. Among these diseases, soybean seed decay is caused by Diaporthe spp. Infecting the pods, and the infected seeds show rotting symptoms. Most diseased seeds are removed during the selection process; however, it is difficult to distinguish infected seeds that do not display symptoms. Hence, a sequencebased method was devised to screen Diaporthe-infected seeds. Based on the nuclear ribosomal internal transcribe spacer (ITS) region of the pathogen, a primer was designed to distinguish the infection from other soybean seed pathogens. As a result of the comparison between healthy and Diaporthe-diseased seeds by using the primers, Diaporthe was detected only in the diseased seeds. Therefore, it is possible to distribute healthy soybean seeds by detecting Diaporthe-diseased seeds at the genetic level using the Diaporthe-specific primers.

• 한국식물병리학회지
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• 제14권5호
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• pp.526-530
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• 1998

The effect of field sanitation using ecological characters of the pathogen was investigated for controlling Phomopsis seed decay in soybean. Field sanitation which was eliminated the inoculum by removing host debris, abscised petioles and cotyledones out of field, reduced remarkably infection percentage of pods and seeds by Phomopsis spp. as compared to the inoculated field. Neverthless, seed infection was 28.7% in the sanitized field. The fields sanitized by benlate application around the soybean plants also decreased seed infection with Phomopsis spp. Total seed infection including that with miscellaneous pathogens occurred as much as 75∼79% to the no application and their control values were 34∼42% over the routine application schedule. Even though it was not satisfactory, field sanitation seemed to be effective in controlling Phomopsis seed decay when infection pressure was low level. Diaporthe phseolorum va. sojae, D. phaseolorum var. caulivora and Phomopsis longicolla were mostly identified from soybean seeds and Colletotrichum truncatum, Cercospora kikuchiana were also isolated in sequence. Field sanitation did not significantly increase in soybean yield over the no application, while routine application schedule did in field.

• The Plant Pathology Journal
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• 제18권4호
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• pp.216-220
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• 2002

Seed decay of soybean caused by Diaporthe phaseolorum, Colletotrichum truncatum and Cercospora kikuchii is a serious disease when soybean is harvested under warm and wet weather conditions. Benomyl has been used for controlling the disease, however, benomyl application may be limited due to common occurrence of resistance. The efficacy of 21 fungicides against the pathogens was evaluated in vitro. Among the fungicides tested, benomyl, carbendazim, fluazinam, iprodione+propineb, thiophanate-methyl, and triflumizole were found effective and were evaluated for their ability to control the seed pathogens. Fluazinam completely inhibited mycelial growth at a concentration of 100 $\mu\textrm{g}$/$\textrm{m}{\ell}$ for D. phaseolorum; and at a concentration of 500 $\mu\textrm{g}$/$\textrm{m}{\ell}$ for C. truncatum and C. kikuchii. $EC_90$ values of fluazinam were similar to that of benomyl. Because fluazinam, iprodione+propineb, and triflumizole were found effective against the seed pathogens, these were subjected for field-testing. Suppression of pod and seed infection by fluazinam and iprodione+propineb was as high as that of benomyl without any reduction in agronomic characters of soybean. This study shows that fluazinam and iprodione+propineb may be used in combination with benomyl to control seed pathogens, manage resistance, and ensure production of high quality soybean seeds.

• 한국식물병리학회지
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• 제10권3호
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• pp.222-227
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• 1994

Effects of field applications of benomyl on Phomopsis seed decay of early soybeans were investigated at Suwon in 1992 and 1993. Pod and immature seed infections were markedly suppressed by benomyl application at the R6 stage whereas the spray at the R7 stage was not as effective as the spray at R6. When compared with unsprayed plots, benomyl spray at R6 resulted in decrease in Phomopsis seed infection by 37.1% and 73.9%, and increased in frequency of seed germination by 1.8% and 8.0% in 1992 and 1993, respectively. The results indicated that only one spray at early R6 could effectively reduce seed infection by Phomopsis spp.and could be adopted in a disease management program for commercial production of healthy soybean seeds.

• 한국작물학회지
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• 제41권2호
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• pp.178-187
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• 1996

풋콩 조생품종들인 오꾸하라와세, 미카와시마, 화엄풋콩 및 석량풋콩의 4품종을 고냉지인 철원과 평창 및 평야지인 수원과 대구의 4개 지역에 1992년 5월15일과 6월15일 2회 파종하여 수확종실의 병해정도와 품종에 따라 6~7개월의 저온 저장후(5$\pm$1$^{\circ}C$) 발아율을 검토하였던 바, 그 결과를 요약하면 다음과 같다. 1. 종실의 병감염은 미이라병 나병률이 가장 높았고, 다음으로 갈반병이었으며 갈반병 나병이 가장 낮았다. 2. 종실의 미이라병, 갈반병 및 자반병 나병을 포함한 총 병해립율은 평창지역이 가장 낮았고, 6월15일 파종이 5월I5일 파종보다 낮은 경향을 보였다. 3. 종실의 미이라병 나병립율은 고냉지인 평창과 철원이 평야지인 수원과 대구보다 낮았고, 6월 15일 파종이 5월I5일 파종보다, 성숙기수확이 성숙후10일 수확보다 낮았다. 4. 종실의 저장후 발아율은 고냉지인 평창과 철원이 90% 이상으로 높아 평야지인 수원과 대구보다 높았으며 6월15일의 만파가 5월15일 파종보다 높았다. 5. 풋콩종실의 미이라병 나병이 낮고, 발아율이 높은 양질종자를 생산키 위해서는 국내 고냉지에서 6월15일의 만파가 유리하였다.

• 한국작물학회지
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• 제53권3호
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• pp.303-307
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• 2008

Cotyledon Black Decay (CBD) on soybean sprout mimics the black spot due to microbial infection. CBD, not visible or predictable at seedlot state, for some reason, shows up exclusively on cotyledon of soybean sprout during sprouting process. Such an incidence rate fluctuated from 0.8 to 19.5% over three years from 2004. We suspected some pod-infecting anthracnose fungi and/or pod-blight pathogen, or pod-sucking bean bug, one of the major pests of soybean, might have involved, of which we ruled out fungal pathogen because it was preventable through heat treatment, a proven method for seedlot disinfestation. The healthy seeds artificially fed by bean bug for one to seven days were sprouted, and 6 to 41% of the soybean sprout revealed the CBD mimic to those occurred in soybean sprout from previous commercial seedlot screening experiments. This finding is the first report to confirm that bean bug damage to pod at $R_8$ stage is directly responsible for the CBD, which did not concur with any other deleterious effects on sprouting such as reduction in hypocotyls elongation and rooting except unsightly sprout quality. However, earlier feeding either at green pod or greenish yellow pod stage ($R_6$ -early $R_7$ stage) resulted in rather severe damages, which strikingly reduced hypocotyls growth to about one forth to about two third, as well as the reduction in rates of seed germination.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2006년도 한국약용작물학회 공동춘계학술발표회
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• pp.142-143
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• 2006

• 한국작물학회지
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• 제40권1호
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• pp.44-51
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• 1995

도입에 의존하고 있는 풋콩 종자 생산체계를 확립하고자 조숙성 품종인 큰올콩과 풋콩 도입풍종인 Fukura 피두를 평야지（영남농업시험장） 및 고랭지（경남 밀양군, 사자평 ：해발 850m）에 파종시기（5월 15일, 6월 15일, 7월 15일）를 달리하여 생육 및 수량과 병해립 및 저장후 발아력을 조사한 결과를 요약하면 다음과 같다. 1. 파종시기가 빠를수록 협수가 많고 100립종은 무거웠으며 수량도 높았다. 재배지별로는 평야지가 고랭지보다 증수되었고, 큰올콩이 Fukura보다 수량성이 높았다. 2. 남부지방의 산간 고랭지는 평야지에 비해 생육 및 100립종이 저하하고 수량성이 크게 떨어져 평야지보다 불리하였다. 3. 안전립 수량은 파종시기가 빠를수록 높고, 평야지 및 큰올콩품종에서 증수되었으며, 전체 립종에 대한 안전립 비율은 고랭지에서 높게 나타났다. 4. 파종시기에 따른 병해정도는 큰올콩은 뚜렷한 차이가 없었으나 Fukura는 파종기가 빠를수록 나병립율이 높았고, 미이라병은 파종기가 빠를수록 심하게 발생하였으며 자정병은 파종기가 늦을수록 많이 발생하는 경향이었다. 5. 종자의 발아율은 파종기가 늦은 것이 높았으며, 5월 15일에 파종하여 수확ㆍ저장한 종자의 발아율은 매우 낮아 문제시 되었다. 따라서 풋콩 종자생육을 위한 적정파종시기는 수파기의 고온ㆍ다습한 환경을 고려하여 6월 중순경이 좋을것으로 생각되었다.

• 한국자원식물학회지
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• 제19권2호
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• pp.204-208
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• 2006

콩나물의 생산과정에서 야기되고 있는 부패를 방지하기 위한 다양한 방법이 제시되고 있다. 본 연구는 물에 침종하는 수침(水浸)을 이용한 종자정선과 0.1% acetic acid에 2분간 실시한 종자소독이 콩나물의 발아와 생장, 형태 및 생산수율에 미치는 영향을 조사하고자 실시하였던 바 그 결과를 요약하면 다음과 같다. 1. 물에 뜨는 부유 종자의 비율은 5분간 물에 침종시킨 종자를 건져 40분간 aeration 시켜 다시 물에 침종시킬 경우 가장 높았다. 2. 상품으로 판매가 가능한 하배축 길이가 4cm이상의 비율은 은하콩에서는 水浸(水浸)과 acetic acid 처리간 차이가 없었던 반면, 풍산 나물콩과 준저리에서는 acetic acid 처리에 비하여 가결 수침 처리(水浸 處理)에서 높았다. 3. 세근형성 비율과 개체당 세근수는 은하콩과 준저리에서는 수침 처리(水浸 處理)에서, 풍산나물콩은 acetic acid 처리에서 상대적으로 높고 많았다. 4. 개체당 전체생계중은 은하콩과 풍산나물콩에서는 수침 처리(水浸 處理) 보다는 acetic acid 처리에서 많았던 반면. 준저리는 이와 반대의 결과를 보였다. 그러나 준저리를 이용한 대량생산 체계에서의 생산 수율은 수침(水浸)을 이용한 종자정선과 acetic acid를 이용한 종자소독간에 차이가 없었다.