• Weed & Turfgrass Science
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• 제3권4호
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• pp.378-381
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• 2014

Zoysiagrass는 대표적인 난지형 잔디로 Curvularia leaf spot, Large patch, Rhizoctonia blight, Spring dead spot, 그리고 Dollar spot 등의 다양한 병에 직면해 있으며 최근에는 많은 병원균들의 복합 감염에 의한 잔디병 양상을 보이고 있다. 최근에 패취형태의 병반을 가진 zoysiagrass 엽조직으로 부터 Rhizoctonia 속과 유사한 곰팡이를 분리하였다. 리보소옴 DNA의 염기서열을 분석하여 Waitea circinata 균주들과 98% 이상의 상동성을 보였고, Koch's 법칙에 따라 zoysiagrass에서 병원성을 확인하여 이 병의 주 원인균은 Waitea circinata로 판명되었다. 따라서 본 병은 zoysiagrass에서 Waitea circinata에 의해 최초로 국내에서 발생한 병으로 사료되며, 기본 병명과 동일하게 Waitea ring patch로 사용하기를 제안하고자 한다.

• 한국작물학회지
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• 제44권4호
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• pp.382-390
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• 1999

In order to identify the responses of Korean soybean cultivars to sudden death syndrome (SDS), forty-two Korean cultivars and three check cultivars (Hartwig and PI 520733 are resistant; Hartz 6686 is susceptible) were tested with sorghum seed inoculum infested with Fusarium solani f. sp. glycines isolate 171 in the greenhouse. This isolate has blue pigment cultural shape on potato dextrose agar (PDA) medium. All Korean cultivars inoculated with F. solani isolate 171 showed the typical SDS symptoms and disease severity on soybean leaves in each cultivar varied at 4 weeks after inoculation. Nine cultivars were included in the most SDS susceptible group and six cultivars were included in the most susceptible group based on Duncan＇s multiple range tests (P$\leq$0.05). In results of the LSD analysis for SDS the resistant group, a total of twenty-five Korean cultivars were included in the same SDS resistant group as PI 520733 or Hartwig and fourteen Korean cultivars were included in the same SDS susceptible group as Hartz 6686. In the second experiment, ten Korean cultivars, ten U.S. cultivars, and one introduced line were compared in the same way as the first experiment Disease severity ranking of check cultivars, Hartwig, PI 520733, and Hartz 6686, were the same as in the first experiment. Within Korean cultivars, seven cultivars showed the consistent severity proportions of leaf symptoms. Disease rankings of these cultivars in this experiment were the same as those in the first experiment. Three US cultivars: Hartwig, Hartz 5454, and Forrest, three Korean cultivars： Keunolkong, Myeongjunamulkong, and Jinpumkong 2, and one introduced line, PI 520733, were included in the highest SDS resistant group. Shinphaldalkong 2, Milyang 87, and Samnamkong consistently showed the highest SDS susceptibility in both experiments. Average disease severity in the first and the second experiment were 49.56% and 45.39%, respectively.

• The Plant Pathology Journal
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• 제30권4호
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• pp.355-366
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• 2014

In this study, resistance responses were investigated during the interaction of Botrytis fabae with two faba bean cultivars expressing different levels of resistance against this pathogen, Nubaria (resistant) and Giza 40 (susceptible). Disease severity was assessed on leaves using a rating scale from 1 to 9. Accumulation levels of reactive oxygen species (ROS), lipid peroxidation and antioxidant enzymes (superoxide dismutase, catalase and ascorbate peroxidase) were measured in leaf tissues at different times of infection. The expression profiles of two pathogenesis-related proteins (PRPs) encoded by the genes PR-1 and ${\beta}$-1,3-glucanase were also investigated using reverse transcription RT-PCR analysis. The accumulation of these defense responses was induced significantly in both cultivars upon infection with B. fabae compared with un-inoculated controls. The resistant cultivar showed weaker necrotic symptom expression, less ROS accumulation, a lower rate of lipid peroxidation and higher activity of the enzymatic ROS scavenging system compared with susceptible cultivar. Interestingly, ROS accumulated rapidly in the resistant leaf tissues and peaked during the early stages of infection, whereas accumulation was stronger and more intense in the susceptible tissues in later stages. Moreover, the response of the resistant cultivar to infection was earlier and stronger, exhibiting high transcript accumulation of the PR genes. These results indicated that the induction of oxidant/antioxidant responses and the accumulation of PRPs are part of the faba bean defense mechanism against the necrotrophic fungus B. fabae with a different intensity and timing of induction, depending on the resistance levels.

• 한국환경농학회지
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• 제23권3호
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• pp.128-132
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• 2004

공시된 세 품종의 고추에 대한 단기간의 오존 처리로 잎에서 나타나는 전형적인 증상은 갈색의 괴사 반응이었으며, 괴사가 심했던 오존 감수성인 다보탑과 같은 농도에서 괴사가 전혀 없었던 부촌 품종을 오존 저항성 품종으로 판단되었다. 고추의 두 품종에서 오존 처리에 의해 광합성 및 기공 전도도 등의 생리생태적 저해가 뚜렷이 나타났다. 그러나 잎에서 가시피해의 정도와 생리생태적 저해 정도와의 상호 연관성으로 고추에서의 오존 저항성 기작을 설명하고자 하였으나 생리생태적 반응으로 잎에서 발생하는 오존 저항성의 기작을 설명할 수 없었다. 다만, 고추에서 오존 처리에 의한 광합성 감소는 뚜렷한 기공전도도 감소와 명반응에서 광합성 기구들의 손상에 기인한다고 여겨진다. 그러나, 암반응에서 생화학적 반응을 설명할 수 있는 A-Ci curve 상에서는 오존 처리에 따른 효과를 찾을 수 없었다.

• 식물병연구
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• 제10권2호
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• pp.112-116
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• 2004

보통답에서 마른 상태의 잔재볏짚이 젖은 상태의 볏짚에서 보다 병원균의 분리빈도가 높았고, 염해답에서는 중간정도 젖은 상태의 볏짚과 완전히 젖은 상태의 볏짚에서 병원균의 분리빈도가 높았으며, 보통답보다는 염해답에서 병원균의 분리빈도가 대체적으로 높았다. 벼깨씨무늬병균은 벼에 포자현탁액을 접종한 후 습실상에서 6시간 유지시키면 침입이 되어 발병이 되었으며, 추청벼에서는 14시간, 대산벼와 Tetep에서는 24시간에 최대 발병율을 나타냈다. 엽령이 많은묘(63일묘)가 엽령이 어린묘(21일-49일묘)보다 병에 대해 감수성이었다. 병반은 품종과 엽위에 관계없이 비교적 고르게 분포되었으며, 대산벼와 추청벼에서 상위에 있는 제 5엽이 하위에 있는 잎들보다 감수성이 높은 경향이었으며, Tetep에서는 뚜렷한 경향이 나타나지 않았으나, 하위엽에서 병반수가 많은 경향이었다. 광의 조사와 발병과의 관계에서는 암처리한 벼가 온실조건 3,000 Lux와 6,000 Lux의 광을 조사한 벼보다 발병정도가 현저히 적은 경향이었다.

• The Plant Pathology Journal
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• 제20권2호
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• pp.106-109
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• 2004

A leaf blight disease was found on Ailanthus altissiman growing in the Manchon Mountain Park in Daegu city. When isolated, the causal fungus readily formed sex organs, being homothallic. Oogonia were spherical, 19.5-42.9 ${\mu}{\textrm}{m}$ in diameter with an average of 29.4$\pm$4.2 ${\mu}{\textrm}{m}$. Antheridia were amphigynous, round to ovoid, and measured 11.3-15.0 ${\mu}{\textrm}{m}$ long and 12.5-14.5 ${\mu}{\textrm}{m}$ wide. Oospores in the oogonia were spherical, 26.1-29.0 ${\mu}{\textrm}{m}$ in diameter. Sporangia that formed in water were spherical to sub-spherical with a conspicuous papilla and measured 19.5-56.6 ${\times}$ 15.6-44.9 ${\mu}{\textrm}{m}$ with an average of 44.0$\pm$8.7${\times}$32.7$\pm$6.3 ${\mu}{\textrm}{m}$. The mean length/breadth (I/b) ratio was 1.35. Papillae were 3.9-11.7 ${\mu}{\textrm}{m}$l high and 3.9-9.8 ${\mu}{\textrm}{m}$ wide. Sporangia formed slowly on V8 juice agar medium when cultured under fluorescent light at 12-hour alternation. The sporangia that formed on the agar medium were more spherical and measured 26.5-39.0${\times}$23.4-35.1 ${\mu}{\textrm}{m}$ with an average of 33.6$\pm$3.4${\times}$28.2$\pm$3.2 ${\mu}{\textrm}{m}$ and I/b ratio of 1.19. Disease symptom was repro-duced by artificial inoculation of the healthy plants with the isolate. The causal organism was identified as Phyto-phthora boehmeriae on the basis of its morphological characteristics.

• 한국작물학회지
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• 제42권2호
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• pp.160-165
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• 1997

팥 바이러스병에 대한 기초자료를 얻고자 병징의 유형과 생육 단계별 감량정도 및 수량에 미치는 영향을 조사하고 병징 유형별 바이러스를 분리 동정한 결과는 다음과 같다. 1. 팥에 발생되는 바이러스병의 병징은 크게 mosaic, yellow mosaic 및 severe mosaic의 3가지 군으로 분류되었으며 병징별 분포는 mosaic＞severe mosaic＞yellow mosaic 순이었다. 2. 성숙기까지 매개충 차단 재배시의 이병률은 1.5%(방임구 20.7%)로서 생육 후기에 감량될수록 이병률이 낮았으며 10a당 수량도 171kg으로서 방임구에 비하여 45% 증수되었다. 3. 지표식물 검정 결과 mosaic 유형은 CMV, yellow mosaic 유형은 AMV, severe mosaic 유형은 AzMV의 기주범위와 유사하였다. 4. 항혈청에 의한 각 병징별 반응결과 yellow mosaic 유형의 시요는 AMV 항 혈청과 mosaic 유형의 시요는 CMV의 항혈청과 침강선이 형성되어 각각 AMV 및 CMV의 한 계통으로 판정되었다. 5. 병징 유형별 전자현미경 관찰결과 yellow mosaic유형은 18~58$\times$18nm의 타원형 입자가 다수 관찰되었고 mosaic 증상의 시요에서는 직경 30nm의 구형 입자, severe mosaic병징의 시요에서는 730$\times$12nm의 사상형 입자와 봉입자가 관찰되었다.

• The Plant Pathology Journal
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• 제36권3호
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• pp.267-279
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• 2020

Fig mosaic is a viral disease (FMD) that spreads in Palestinian common fig (Ficus carica L.) orchards. Recognizing the economic value of fig plants and the harmful nature of FMD, the disease poses a significant threat to the economy of the fig production in Palestine. We applied the reverse transcription and amplification (RT-PCR) and PCR technique to leaf samples of 77 trees and 14 seedlings of 17 fig cultivars. The samples were collected from orchards in the main fig-growing provinces of the Palestinian West Bank, to assess the prevalence of viruses associated with FMD, and confirm a possible link of symptoms with viruses detected. Four viruses were detected: Fig mosaic virus (FMV), Fig badnavirus-1 (FBV-1), Fig leaf mottle-associated virus 2 (FLMaV-2), and Fig fleck-associated virus (FFkaV). FMV and FBV-1 were found in all tested fig plants (100%), while FLMaV-2 and FFkaV were detected in 61.5% and 33% of the fig samples, respectively. The high incidence of FBV-1 in the newly propagated symptomatic and symptomless seedlings from different cultivars may be an indication that FBV-1 is integrated into the genome of the fig in a cultivar nondiscriminatory manner. Very weak or no association was detected between FMD symptoms severity in the 17 Palestinian fig cultivars with the various viruses' combinations observed (i.e., number of the viruses infecting the plant). These results support the notion that FMD symptom severity expression is likely to be controlled by a combination of FMV infection, cultivars, and environmental factors, rather than the number of viruses infecting the plant.

• Weed & Turfgrass Science
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• 제1권4호
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• pp.76-79
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• 2012

골프장에서 잔디혹응애에 의한 들잔디 피해와 형태적 특징을 조사하여 골프장 잔디관리의 기초자료를 제공하고자 연구를 수행하였다. 잔디혹응애는 경기도 포천에서 경남 진주까지 전국적으로 발생하고 있었으며 봄부터 가을까지 피해가 나타났다. 피해 받은 잔디는 엽의 한쪽면이 말리고, 응애는 말린 잎 안에서 가해하였다. 피해잔디의 말려진 부분은 황화 되었으며 골프장에서는 회색의 불규칙한 패치형 병반을 형성하고 있었다.

• 한국육종학회지
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• 제41권4호
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• pp.377-384
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• 2009

Three-year-old seedlings of susceptible Pinus densiflora and resistant Pinus x rigitaeda were each inoculated with the pinewood nematode, Bursaphelenchus xylophilus, to compare disease development. Needle dehydration was evident on seedlings of P. densiflora by 20 days after inoculation, 10 days earlier than this symptom was observed on P. ${\times}$ rigitaeda. Xylem drying was more frequent in seedlings of P. densiflora than in that of P. ${\times}$ rigitaeda between 20 and 60 days after inoculation. No significant differences were found between P. densiflora and P. ${\times}$ rigitaeda for stem water content or for stem and leaf relative water content in current-year branches after nematode inoculation, but the average number of B. xylophilus recovered from stems differed significantly between the two groups. The number of B. xylophilus recovered from stems was negatively correlated with the stem water content and with stem and leaf relative water content. By the time the experiment was terminated at 60 days after inoculation, all 3 of the last group of P. densiflora seedlings had died, but 2 of the 3 remaining P. ${\times}$ rigitaeda hybrid seedlings were still alive. Additional studies are needed to further explore the specific mechanisms preventing nematode multiplication in the seedlings of resistant P. ${\times}$ rigitaeda.