• 한국균학회지
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• 제11권1호
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• pp.27-32
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• 1983

Five species of the genus Pythium were identified from 91 isolates which were collected from rice seedlings in machine transplanting nursery boxes and paddy fields in Korea. They included P. graminicola complex, P. monospermum complex, P. rostratum complex, and P. ultimum complex. The most frequently found species of the genus Pythium was P. graminicola complex followed by P. monospermum complex. Rice seed germinability was greatly decreased by being infested with P. graminicola complex at nursery box. P. graminicola complex was the most virulent in terms of prohibiting germinations and stunting plants in nursery boxes.

• 한국균학회지
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• 제11권3호
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• pp.105-108
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• 1983

The mycelial growth of Pythium graminicola, P. ultimum, P. rostratum was best at -3 osmotic potential. P. monospermum was best grown at -8 bars osmotic potential. Mycelial growth by Pythium spp. was prevented at -42 bars for P. graminicola, P. ultimum and P. monospermum. Sporangial formation by P. graminicola and P. ultimum was influenced by water potential in much the same way as mycelial growth: -3 bars was maximum and -42 bars or below was minimal. Pythium spp. tested was grown faster on PDA than other media including oat meal agar. P. ultimum was best grown on any media among Pythium spp. tested.

• Weed & Turfgrass Science
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• 제2권1호
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• pp.70-75
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• 2013

본 연구에서는 7종의 약용식물(송절, 지구목, 측백, 대풍자, 유백피, 은행잎, 참오동나무)을 사용하여 잔디의 주요 병원균 6종(R. solani AG 2-2(IV), R. solani AG-1 IB, Pythium sp., S. homoeocarpa, R. cerealis, C. graminicola)을 대상으로 항진균 활성을 실험하였다. 디스크 확산법으로 항진균 활성이 있는 약용식물 추출물을 선발하였고, 선발된 추출물을 사용하여 균사생육 억제 효과를 검정하였다. 디스크 확산법으로 실험 한 결과 7종의 약용식물 중 송절, 측백, 유백피 등 3종의 추출물에서 항진균 활성이 있는 것으로 나타났다. 송절 추출물 1,000배 처리에서 Pythium sp.에 대하여 100%, C. graminicola에 대하여 84.3%의 균사생육 억제율을 나타내었으며, 특히 Pythium sp.에 대해서는 5,000배 처리에서도 89.5%의 균사생육 억제율을 나타내었다.

• The Plant Pathology Journal
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• 제15권2호
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• pp.112-118
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• 1999

Eleven species of Pythium were isolated from leaf blight symptoms on creeping bentgrass (Agrostis palustirs Huds.), Kentucky bluegrass (Poa pratenisis L.) and zoysiagrasses (Zoysia japonica Steud., and Z. matrella (L.) Merr.) planted on golf courses in Korea. Mycelial growth on potato carrot agar medium under various temperature conditions indicated that Pythium species obtained in this study could be divided into four groups based on their responses to temperature conditions. P. vanterpoolii was found to favor low temperature conditions with the optimum temperature of $25^{\circ}$, whereas P. aphanidermatum and P. myriotylum favored relatively high temperature conditions with the optimum temperature of $35^{\circ}$. Other species including P. arrhenomanes, P. catenulatum, P. graminicola, P. oligandrum, P. rostratum, P. torulosum, and P. ultimum were the intermediate group with the optimum temperature of 25~$35^{\circ}$. P. periplocum was similar to the intermediate group but the minimum temperature for its mycelial growth was $15^{\circ}$, which was approximately $5^{\circ}$ above that for the intermediate Pythium spp.group. In the pathogenicity tests conducted in the lab using potted plants, P. aphanidermatum, P.a arrhenomanes, P. catenulatum, P. graminicola, P. myriotylum, P. periplocum, P. rostratum, P. torulosum, P. ultimum, and P. vanterpoolii were found to be pathogenic to creeping bentgrass and Kentucky bluegrass. P. aphanidermatum, P. catenulatum, and P. graminicola were frequently isolated from leaf blight symptoms of creeping bentgrass and Kentucky bluegrass in golf courses during the warm and humid periods in July-August. On the other hand, P. vanterpoolii and P. torulosum were frequently isolated during the cool and humid periods in March-May, suggesting both species might be the major causes of leaf blight occurring in the spring time. Zoysiagrass was susceptible to P. arrhenomanes and the heterothallic Pythium sp. (Ht-F), showing stem and crown rot of turf-grasses at poorly drained areas under coool and humid or rainy conditions. P. oligandrum and the heterothallic Pythium sp. (Ht-L) isolated from creeping bentgrass were avirulent to all species of turfgrasses tested in this study.

• Mycobiology
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• 제32권1호
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• pp.35-41
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• 2004

A total of 374 Pythium isolates were isolated and identified from the rhizosphere soils of maize plants grown in 100 different agricultural fields in nine provinces at El-Minia Governorate, Egypt. Five Pythium spp. of P. deliense, P. graminicola, P. irregulare, P. oligandrum and P. splendens were obtained P. deliense and P. oligandrum were predominant in all of the locations with 48.1% and 41.4% of total counts, respectively. P. graminicola, P. irregulare and P. splendens were not isolated in 4, 2 and 4 provinces out of 9 provinces with 5.3%, 3.5%, and 1.6% of isolation percentage from total counts, respectively. Number of Pythium isolates in each were 34, 31, 34, 33, 34, 96, 37, 37 and 38 out of 374, for locations of El-Edwa, Maghagha, Beni-Mazar, Matai, Samalout, El-Minia city, Abou-Querquas, Mallawi and Der Mawas, respectively. Pre- and post-emergence pathogenicity tests indicated that only P. deliense was highly pathogenic to germinating grains and seedlings of maize whereas P. oligandrum was non-pathogenic.

• 한국균학회지
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• 제18권4호
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• pp.181-190
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• 1990

The growth and biochemical activities of Chlorella fusca were studied in the presence of different concentrations of either filtrates or mycelial mats of Saprolegnia ferax and Pythium graminicola. Low concentrations of both fungal filtrates exerted increase in total count, dry weight and in the biosynthesis of photosynthetic pigments, carbohydrates and nitrogen content. High concentrations showed inhibitory effect on both growth and biochemical activities of Chlorella fusca. Supplementation with different concentrations of dry mycelial mats of either fungi the culture of Chlorella showed elevation in biomass, dry weight, and biosynthesis of carbohydrates and nitrogen content especially at low concentrations. The contents of photosynthetic pigment were inhibited only at low concentrations. Neither the culture filtrate of Pythium nor Saprolegnia had cellulolytic activity, although polygalacturonase enzymes were detected, whereas chloroform-extract of both fungal filtrates showed blue spots under long wave light (366 nm).

• 아시안잔디학회지
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• 제13권4호
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• pp.223-234
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• 1999

Antibiotic activity of selected biocontrol agent Trichoderma harzianum ABGS-95 showed 59% to P. graminicola, 65% to P. aphanidermatum and 57% to Rhizoctonia solani compare to non-treated control. ABGC-95 showed resistant to major agrochemicals such as metalaxyl+mancozeb, etridiazole, propamocarb, toclofos methly, terbuconazole, pencycuron and flutolanil. The biocontrol agent T. harzianum ABGC-95 grew vigorously in low nutrient media and water agar. And sand mixture with wheat bran or mowing debris of zoysia grass also provided good growth of the organism. Application of sand mixture of Trichoderma spp. into aeration cores in golf showed most effective biocontrol of pythium blight. Top dressing application of T. harzianum ABGC-95 reached 83% control efficient while spray application of same biocontrol agent showed only 69% control. The biocontrol agent ABGC-95 successfully suppressed the population density of Pythium spp. in soil. The population density of total Pythium spp. in ABGC-95 treated soil was sustained almost same population at beginning(early May) up to end of August, while the population in untreated control plot was increased 5 times that of beginning and even 10 times in pathogen accumulated soil.

• 한국균학회지
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• 제30권2호
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• pp.157-165
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• 2002

국내 35개 골프장에 식재된 잔디류의 잎마름 증상으로부터 분리한 125개 Pythium spp. 균주 중 분리시기별, 골프장별 그리고 Pythium spp. 별로 선발한 44개 균주를 사용하여 실내실험을 통해 metalaxyl에 대한 감수성정도를 조사하였다. 다양한 농도(0, 0.1, 1.0, 10.0, 50.0, 100.0 및 $250.0{\mu}g\;a.\;i./ml$)로 metalaxyl을 함유한 Difco corn meal agar 배지에서 균사생장억제 정도를 조사한 결과 1.0과 $10.0{\mu}g\;a.\;i./ml$수준의 metalaxyl에 대해 감수성정도에 따라 크게 2 group으로 나눌 수 있었다. Metalaxyl 함량이 $10.0{\mu}g\;a.\;i./ml$에서 균사생장억제율은 감수성 group에 속한 31개 균쥬는 $66{\sim}98%$, 저항성 group에 속한 13개 균주는 $6{\sim}26%$이었고. $10.0{\mu}g\;a.\;i./ml$에서는 각각 $82{\sim}99%$와 $27{\sim}47%$를 나타냈다. 이처럼 metalaxyl에 저항성을 나타내는 Pythium spp.의 출현과 골프장 잔디에서의 분리는 국내에서 처음 보고되는 것이다. Metalaxyl에 저항성을 나타낸 Pythium spp. 균주 중 분리빈도가 상대적으로 높았던 P. graminicola 중 metalaxyl에 감수성을 나타내는 4개 균주와 저항성을 나타내는 3개 균주를 이용하여 pot 내 creeping bentgrass에 대하여 농약 스크리닝시험을 한 결과 metalaxyl 감수성 균의 경우 $6.25{\mu}g\;a.\;i./ml$ 처리구에서는 병 발생이 없었지만 저항성 균의 경우는 $12.5{\mu}g\;a.\;i/ml$와 그 이상의 처리구에서도 방제가 되지 않았다. 50.0과 $100.0{\mu}g\;a.\;i/ml$ 처리구에서는 creeping bentgrass에 약해를 나타냈다. 병원균 접종 전 약제처리가 발병 후 처리에 비하여 우수한 방제효과를 나타냈다.

• 한국균학회지
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• 제25권4호통권83호
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• pp.276-290
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• 1997

1990년부터 1996년에 걸쳐 전국 35개 골프장에서 한지형잔디인 creeping bentgrass, Kentucky bluegrass 그리고 난지형잔디인 zoysiagyass의 잎마름 증상으로부터 Pythium spp. 125균주를 분리 하였고, 이를 동정한 결과 P. aphanidermatum, p. arrhenomanes, P. catenulatum, p. gramlnicola, p. myriotylum, P. oligandrum, P. periplocum, P. rostratum, P. torulosum, P. ultimum Trow var. ultimum 그리고 P. vanterpoolii로 모두 11개 종으로 동정되었다. 본 실험에서 사용한 semi-solid 상태의 'sucrose-asparagine bentgrass leaf culture' 방법을 이용할 경우 Pythium spp.의 동정에 필요한 포자낭, 장란기, 장정기 그리고 난포자의 형태적 특징의 관찰이 용이하였다. 동정된 Pythium spp.는 국내에서는 잔디류에 대하여 처음 보고되는 것이고, 이 중에서 P. arrhenomunes, P. cutenulatum, P. graminioota, P. oligandrum, P. periplocum, P. rostratum, P. torulosum 그리고 P. vanterpoolii는 국내에서 처음 보고되는 미기록종이다. P. myriotylum, P. rostratum, P. torulosum, P. vanterpoolii의 경우는 PCA 배지상에서 특이한 균사생장형을 나타내므로 이를 균 동정에 이용할 수 있었다.

• 아시안잔디학회지
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• 제24권2호
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• pp.176-181
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• 2010

잔디에 발생하는 주요 병해로 한지형 잔디에서 갈색잎마름병(Rhizoctonia solani AG1-1), 동전마름병(S. homoeocarpa), 피시움마름병(Pythium. spp.), 탄저병(C. graminicola)과 난지형 잔디에서 누른잎마름병(R. cerealis), 라이족토니아마름병 (R. solani AG2-2)이다. 본 연구에서는 이들 잔디 주요 병원균 6종에 대한 한약재 23종의 항진균 활성을 알아보았다. 디스크 확산법으로 항진균 활성이 있는 한약재를 선발하였고, 선발된 한약재를 대상으로 균사생육억제 효과를 실험하여 검정하였다. 항진균 활성 시험 결과, 한약재 23종 중고삼 외 11종의 시료에서 항진균 활성이 있었으며, 균사생육 억제효과를 통한 검정에서는 10 mg/10 ml(1000배) 추출물 첨가 배지에서 잔디 병원균 6종 중 1종이라도 균사 억제율이 80% 이상인 추출물은 고삼, 울금, 대황, 황련, 족두리풀로 나타났다. 특히 고삼 추출물은 실험 대상인 잔디 병원균 6종에 대해 모두 항진균 활성이 나타났고, 울금 추출물 10 mg/10 ml(1000배), 5 mg/10 ml(2000배), 2 mg/10 ml(5000배) 첨가 배지에서 S. homoeocarpa 에 대해 100% 균사 생육 억제 효과를 나타내었다. 그리고 Pythium spp. 균사 억제효과가 100%인 것은 고삼, 대황, 황련으로 나타났다.