• 식물병연구
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• 제16권1호
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• pp.66-73
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• 2010

2008년 수원과 안동 시헝포장과 2009년 경북 봉화와 충남 태안 농가포장에서 역병, 담배나방, 탄저병의 병충해를 관리하는 고추 종합 예찰 방제 타당성 평가를 실시 하였다. 이병과율과 수확량이 무방제, 예찰방제, 관챙방제 등 세 처리 간에 비교평가 하였다. 2009년 봉화의 두 품종은 예찬방제 처리의 이병과율과 수확량이 각각 3.1-3.5%와 30-33 kg/40주 였 다. 이 는 관행 방제 의 0.3-0.8%와 35-36kg/40주와 비슷하면서도 무방제의 23-27%와 18-24 kg/40주보다 월등한 방제였다. 예찰방제 살포 횟수는 g회 였으나 농가에서 관행방제는 11-19회 였다. 또한 다른 세 포장에서의 탄저병 예찰방제의 결과에서도 탄저병을 방제하면서도 관행방제보다 세균제 사용량과 방제 비용을 줄일 수 있다는 결과를 보여주었다. 그런데, 무방제 탄저병 이병과율이 60-80%이상으로 극심했던 태안 농가의 경우 탄저병 예찰 방제의 보완이 필요하다. 왜냐하면 예찰방제의 방제가는 겨우 무방제와 관행방제의 중간 정도에 머물렀기 때문이다. 만일 재배 초기에 탄저병 발병이 심한 포장이라면, 아직 과실이 익기 전이라도 추가적인 예방 방제가 필요하다.

• The Plant Pathology Journal
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• 제25권1호
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• pp.38-46
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• 2009

Lichen-forming fungi (LEF) were isolated from 67 Hungarian lichen species from ascospores or thallus fragments. LFF were successfully isolated from 26 species with isolation rate of 38.8%. Of the total number of isolation from ascospores (27 species) and thallus fragments (40 species), 48% and 32.5% of the species were successfully isolated, respectively. Comparison of rDNA sequences of ITS regions between the isolated LFF and the original thallus confirmed that all the isolates originated from the thallus fragments were LEF. The following 14 species of LEF were newly isolated in this study; Acarospora cervina, Bacidia rubella, Cladonia pyxidata, Lasallia pustulata, Lecania hyaline, Lecanora argentata, Parmelina tiliacea, Parmotrema chinense, Physconia distorta, Protoparmeliopsis muralis, Ramalina pollinaria, Sarcogyne regularis, Umbilicaria hirsuta, Xanthoparmelia conspersa and X. stenophylla. Antifungal activity of the Hungarian LFF was evaluated against plant pathogenic fungi of Colletotrichum acutatum, C. coccodes and C. gloeosporioides, causal agent of anthracnose on hot pepper. Among the 26 isolates, 11 LFF showed more than 50% of inhibition rates of mycelial growth of at least one target pathogen. Especially, LFF of Evernia prunastri, Lecania hyalina and Lecanora argentata were remarkably effective in inhibition of mycelial growth of all the tested pathogens with antibiotic mode of action. On the other hands, five isolates of Cladonia furcata, Hypogymnia physodes, Lasallia pustulata, Ramalina fastigiata and Ramalina pollinaria exhibited fungal lytic activity against all the three pathogens. Among the tested fungal pathogens, C. coccodes seemed to be most sensitive to the LFF. The Hungarian LFF firstly isolated in this study can be served as novel bioresources to develop new biofungicides alternative to current fungicides to control hot pepper anthracnose pathogenic fungi.

• 식물병연구
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• 제19권2호
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• pp.121-123
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• 2013

사과, 호박, 고추에서 분리된 탄저병균들(Colletotrichum gloeosporioides, C. orbiculare, C. acutatum)이 복분자딸기에 병원성을 나타냈으며. 특히 사과에서 분리된 탄저병균은 무상처 접종에서도 병원성을 나타냈다. 복분자 딸기에서 분리한 탄저병균(Colletotrichum gloeosporioides, C. coccodes, C. acutatum)은 사과와 딸기에서는 dropping 접종에 의해 병원성을 보였으나 고추와 토마토에서는 낮은 병원성을 나타내었다.

• The Plant Pathology Journal
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• 제27권2호
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• pp.156-163
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• 2011

Antifungal activity of three Myxococcus spp., KYC 1126, 1136, and 2001, was tested in vitro against three phytopathogenic fungi (Botrytis cinerea, Colletotrichum acutatum, and Pyricularia grisea). Spore germination and mycelial growth of the three pathogenic fungi were completely inhibited by bioactive substances from a myxobacterium KYC 1126. In addition, the activity of KYC 1126 was fungicidal, but liquid culture filtrate of KYC 1126 did not affect protoplast reversion in C. acutatum. A bioassay of KYC 1126 filtrate against anthracnose in hot pepper was conducted in the greenhouse and field at 2009 and 2010. The incidence of anthracnose in control seedlings was 74%, but was reduced to 29% after KYC 1126 treatment. The control value with KYC 1126 was 60% while that with the fungicide dithianon was 42%. In the greenhouse, disease incidence with KYC 1126 was consistentely 10-35% lower than with fungicide as a positive control. The control value with KYC 1126 was 13.4% and 41.0%, whereas that with the fungicide was 52.3% and 63% in 2009 and 2010, respectively. Although anti-anthracnose activity of KYC 1126 was not maintained for long time in the field, the bacteriolytic myxobacterium KYC 1126 could be a prospective biocontrol agent.

• 한국농림기상학회지
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• 제13권1호
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• pp.10-19
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• 2011

미래 고추탄저병 위험도를 예측하기 위해 남한 지역에서 A1B 시나리오 온실가스 배출에 따라 예측된 일별 기온과 강우량 자료를 국립기상연구소에서 제공받아 고추 탄저병 예찰 모형에 대입하여 감염위험도(IR)을 추정하였다. 감염위험도는 탄저병 방제 횟수를 추정하는 것으로써 일평균 온도와 강우량을 기초로 감염위험도 추정식을 만들었다. 이 추정식(IR=(일평균기온-$16^{\circ}C$) ${\times}$ 0.07 + (일별강우량 ${\times}$ 0.11))을 활용하여 우리나라 135지역에서 2011년부터 2100년까지 총 12,150의 탄저병 권장 방제 횟수 자료를 얻었다. 각 지역별로 135개의 회귀분석 결과 우리나라 전 지역에서 향후 탄저병 발병은 증가 추세라는 것이 확인되었다. 상대적으로 탄저병 발병이 급증하리라 예측되는 지역은 경북의 영덕, 영양, 의성 등이었고, 반면 발병 증가가 완만하리라 기대되는 곳은 강원 횡성, 경남 함양 그리고 충남 태안 등이었다. 현재 고추 주산지인 경북동부지역은 미래 탄저병 발병압이 심각하게 증가되리라 예측되었다. 전 지역에 걸쳐 탄저병 방제 살포 횟수는 2058, 2061, 2078 그리고 2096년에는 대단히 심각하여 방제 경보가 매년 8-11회에 달하리라 예측되었다. GIS 지도로 탄저병 발병 정도를 비교한 결과 충북과 전북의 산간 지역은 상대적으로 탄저병 발병압이 낮아 향후 재배적지로 판단된다.

• The Plant Pathology Journal
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• 제25권3호
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• pp.213-219
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• 2009

An understanding of anthracnose (Colletotrichum acutatum) infections, including the infection of flowers and latent infection early in the season, is necessary to achieve successful control by means of properly timed spraying with a curative fungicide. In the present study, latent anthracnose infection of chili was investigated under greenhouse and field conditions in 2007-2008. Flowers on greenhouse-grown seedlings were infected and 11% of the young fruits subsequently showed symptoms of anthracnose. Apparently healthy-looking green peppers obtained from unsprayed fields or an organic market also exhibited symptoms of anthracnose after 4 days of incubation under high moisture conditions at $25^{\circ}C$; less than 1% of the peppers were found to be latently infected. To determine the natural timing of infection in the field, 3,200 fruits were wrapped in paper bags and then selectively unwrapped and examined for signs of infection. Field experiments were conducted at Suwon (cvs. Yokkang, Manitta, Olympic) and Asan (cv. Chunhasangsa) in 2008. The 7- to 10-day wrapping periods were July 25-31, July 31-August 7, August 7-15, August 15-24, and August 24-September 3. The 1-to 2-month wrapping periods were from July 4, July 31, and August 15 until harvest (Sept. 3). The controls consisted of 1,712 field-grown non-wrapped fruits. The rates of infection on the various cultivars were Yokkang 55%, Manitta 37%, Olympic 55%, and Chunhasangsa 20%. A distinct period in which anthracnose infection suddenly increased could not be identified; however, attempts to guess the approximate timing of field infection showed that 0-39% of the plants had latent infections, while depending on the cultivar, 8-14% of the plants examined in August and 4-13.5% of the those examined during May-July showed symptoms of infection. Delaying fungicide spraying by 24 and 48 h after artificial infection decreased the rates of infection by 10% and 25-30%, respectively. Chemical control of anthracnose based on a forecasting model should be considered starting from the transplanting stage, with spraying within a day after warning and care being taken not to latently infect apparently healthy pepper fruits.

• The Plant Pathology Journal
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• 제29권3호
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• pp.294-304
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• 2013

To improve the integrated pest management (IPM) of hot pepper, field study was conducted in Hwasung from 2010 to 2012 and an IPM system was developed to help growers decide when to apply pesticides to control anthracnose, tobacco budworm, Phytophthora blight, bacterial wilt, and bacterial leaf spot. The three field treatments consisted of IPM sprays following the forecast model advisory, a periodic spray at 7-to-10-day intervals, and no spray (control). The number of annual pesticide applications for the IPM treatment ranged from six to eight, whereas the plots subjected to the periodic treatment received pesticide 11 or 12 times annually for three years. Compared to the former strategy, our improved IPM strategy features more intense pest management, with frequent spraying for anthracnose and mixed spraying for tobacco budworm or Phytophthora blight. The incidences for no pesticide control in 2010, 2011, and 2012 were 91, 97.6, and 41.4%, respectively. Conversely, the incidences for the IPM treatment for those years were 7.6, 62.6, and 2%, and the yields from IPM-treated plots were 48.6 kg, 12.1 kg, and 48.8 kg. The incidence and yield in the IPM-treated plots were almost the same as those of the periodic treatment except in 2011, in which no unnecessary sprays were given, meaning that the IPM control was quite successful. From reviewing eight years of field work, sophisticated forecasts that optimize pesticide spray timing reveal that reliance on pesticides can be reduced without compromising yield. Eco-friendly strategies can be implemented in the pest management of hot pepper.

• The Plant Pathology Journal
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• 제32권3호
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• pp.260-265
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• 2016

We observed the changes in aggressiveness and fecundity of the anthracnose pathogen Colletotrichum acutatum on hot pepper, under the ambient and the twice-ambient treatments. Artificial infection was repeated over 100 cycles for ambient ($25^{\circ}C/400ppm$ $CO_2$) and twice-ambient ($30^{\circ}C/700ppm$ $CO_2$) growth chamber conditions, over 3 years. During repeated infection cycles (ICs) on green-pepper fruits, the aggressiveness (incidence [% of diseased fruits among 20 inoculated fruits] and severity [lesion length in mm] of infection) and fecundity (the average number of spores per five lesions) of the pathogen were measured in each cycle and compared between the ambient and twice-ambient treatments, and also between the early (ICs 31-50) and late (ICs 81-100) generations. In summary, the pathogen's aggressiveness and fecundity were significantly lower in the late generation. It is likely that aggressiveness and fecundity of C. acutatum may be reduced as global $CO_2$ and temperatures increase.

• 농업생명과학연구
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• 제46권3호
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• pp.37-45
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• 2012

고추에 큰 피해를 일으키는 탄저병에 대한 강한 길항력이 있는 세균을 선발하기 위해 선행연구에서 식물뿌리 시료로부터 분리하여 보관중인 세균들을 대상으로 검정에 사용하였다. 총 457균주로부터 IA70-5균주를 최종 선발하였고, 16S rDNA 염기서열 분석을 통해 Streptomyces padanus로 동정하였다. S. padanus IA70-5는 색소를 분비하지 않고 운동성이 없으며 전형적인 Streptomyces속에 속하는 세균들처럼 나선형의 형태를 이루고 있었다. S. padanus IA70-5 균주는 in vitro에서 Colletotrichum acutaum의 균사생장, 포자발아, 그리고 부착기 형성을 효과적으로 억제하였다. 실내 고추 과실에 대하여 병원균 접종 전 IA70-5 배양액 처리 시 약 90%의 탄저병 억제효과를 나타내었다. 본 연구결과를 통하여 길항방선균 S. padanus IA70-5는 고추 탄저병을 억제하는 효과가 있음을 확인하였다.

• The Plant Pathology Journal
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• 제30권3호
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• pp.279-287
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• 2014

KYC 3262 was selected as a biocontrol agent against anthracnose on hot pepper from 813 extracts of myxobacterial isolates. Dual culture with Colletotrichum acutatum and 813 myxobacterial extracts was conducted, and 19 extracts were selected that inhibited germination and mycelial growth of C. acutatum. All selections were Sorangium cellulosum, which are cellulolytic myxobacteria from soil. With the infection bioassay on detached fruits in airtight containers, KYC 3262, KYC 3512, KYC 3279, and KYC 3584 were selected. The listed four myxobacteria were cultured in CSG/1 liquid media, and harvested filtrates were sprayed on the infected fruits. KYC 3262 was selected from the studies of attached fruit in a greenhouse study. KYC 3262 filtrate was applied for 3 years (from 2011 to 2013) in a field study in Asan, Republic of Korea. Control values of the KYC 3262 in the field were 31%, 89%, and 82% in 2011, 2012, and 2013, whereas values of the fungicide spray treatment were 19%, 97%, and 91%, respectively. Yields (kg/20 plants) of the KYC 3262 were 2.66 kg and 18.6 kg in 2011 and 2013, respectively, and those of the fungicide treatment were 2.0 kg and 20.2 kg, in 2011 and 2013, respectively.