• The Plant Pathology Journal
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• 제32권6호
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• pp.489-499
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• 2016

Green shoot cuttings of 10 different grapevine species were inoculated with Agrobacterium vitis to find disease-related metabolites in the grapevine. Crown galls formed 60 days after inoculation varied in gall severity (GS) evaluated by gall incidence (GI) and gall diameter (GD), which were classified into three response types as RR (low GI and small GD), SR (high GI and small GD), and SS (high GI and large GD), corresponding to resistant, moderately resistant, and susceptible responses, respectively. In this, 4, 4, and 2 Vitis species were classified into RR, SR, and SS, respectively. Gas chromatography mass spectrometry (GC-MS) analysis of the grapevine stem metabolites with A. vitis infection showed 134 metabolites in various compound classes critically occurred, which were differentially clustered with the response types by the principal component analysis. Multivariate analysis of the metabolite profile revealed that 11 metabolites increased significantly in relation to the response types, mostly at post-inoculation stages, more prevalently (8 metabolites) at two days after inoculation than other stages, and more related to SS (7 metabolites) than RR (3 metabolites) or SR (one metabolite). This suggests most of the disease-related metabolites may be rarely pre-existing but mostly induced by pathogen infection largely for facilitating gall development except stilbene compound resveratrol, a phytoalexin that may be involved in the resistance response. All of these aspects may be used for the selection of resistant grapevine cultivars and their rootstocks for the control of the crown gall disease of the grapevine.

• 식물병연구
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• 제18권4호
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• pp.331-337
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• 2012

감귤 검은점무늬병은 감귤 재배에 있어서 매우 중요한 병으로 감귤의 상품 가치를 떨어뜨리고 경제적 손실을 유발한다. 다른 감귤병과 마찬가지로 감귤 검은점무늬병 방제에는 주로 화학 농약이 사용된다. 최근 농약의 부작용 때문에 농약을 대체할 수 있는 방제 수단이 절실히 요구되고 있다. 본 연구에서는 감귤 검은점무늬병균 Diaporthe citri에 항균효과가 있는 식물근권세균 TRH423-3, MRL408-3, THJ609-3, TRH415-2을 선발하였다. 이들 세균의 감귤 검은점무늬병에 방제 효과가 있는지 알아보기 위해 감귤 잎에 전 접종한 후 감귤 검은점무늬병균을 접종하였다. 선발된 모든 식물근권세균이 감귤 검은점무늬병에 대해 방제 효과를 나타내었고 방제 정도는 식물근권세균의 균주에 따라 차이가 있었다. 감귤 검은점무늬병균을 접종한 후 추가로 식물근권세균을 접종하였더니 모든 처리구에서 방제 효과가 증진되었다. 한편, 식물근권세균 rDNA의 internal transcript spaces 염기서열을 분석한 결과 MRL408-3와 TRH423-3은 Burkholderia gladioli로, TRH415-2은 Pseudomons fluorescens로 그리고 THJ609-3은 Pseudomonas pudia로 동정되었다. 이들 선발된 식물근권세균은 화학적 방제 수단의 적용이 제한된 친환경 감귤 재배지에서 가치 있게 사용될 수 있을 것으로 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권1호
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• pp.9-16
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• 2007

The present study was aimed to screen different antibiotics in vivo for their effects against the bacterium Bacillus coagulans in silkworm Bombyx mori in three experimental conditions viz., a) healthy larvae treated with the antibiotics b) larvae which were first inoculated with Bacillus coagulans immediately after the $2^{nd}$ moult and treated with the antibiotics from 24 hour after inoculation up to the end of the $5^{th}$ instar(pre-inoculated larvae) and c) larvae which were treated with the antibiotics right from hatching up to the end of the $5^{th}$ instar and inoculated with Bacillus coagulans immediately after the $2^{nd}$ moult(post-inoculated larvae). All the antibiotics used in this study stimulated better performance in improving the rearing performance and economic characters of the cocoons in healthy, pre-inoculated and post-inoculated larvae, besides reducing the mortality of infected larvae. Cephelexin and Tetracycline were more effective than the others in their overall performance under all the three experimental conditions. Chloramphenical caused greater increase in the length of the reelable silk filament, but was not as good in elevating the other parameters compared to the remaining antibiotics. Of the four concentrations of antibiotics tested, 2.0% performed better under all the three experimental conditions.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.133-138
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• 2003

Five seed kernel namely, Neem (Azadirachta indica A. Juss.), Pongamia (Pongamia glabra L. Pierre), Tamarind (Tamarindus indica L.), Mahua (Madhuca indica Gmel.) and Shikakai (Acacia cancinna De.) were tested against hatching of eggs and larval mortality of Meloidogyne incognita causing root knot disease in mulberry along with Furadan (Carbofuran) and Bionema (a bioformulation developed from Verticillium chlamydosporium) for comparison. Results revealed that highest hush-up of hatching was observed in Neem (77.40%) and Pongamia (75.99%) seed kernel extracts at 100% concentration over the check. Similarly, highest larval mortality was observed in Neem and Pongamia by 76.00% and 74.50%, respectively at 100% concentration after 72 hrs of exposure period. Pot culture studies revealed that pre-application of seed kernel powders (20 days before inoculation of nematode) found to be more effective in controlling the root knot disease than post application. In pre application of seed kernel powders, maximum reduction of root knots was observed in case of Neem seed kernel powder (54.85%) followed by Pongamia (51.9%). Similar trend was also observed in reduction of egg masses/plant and nematode population ／250 cc soil. Rest of the seed kernel extracts was found to be less effective in suppression of hatching, enhancing the larval mortality and controlling the root knot disease. However, application of Furadan and Bionema tested for the comparison were found to be more effective than seed kernel powders. The generated information seems to be useful in developing an ecofriendly integrated approach for the control of root knot nematode disease in mulberry.

• KSBB Journal
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• 제32권2호
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• pp.96-102
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• 2017

The lignocellulose that is a major component of spent coffee ground was degraded and saccharified. To implement the spent coffee, after several pre-treatments, inoculation of Phanerochaete chrysosporium and solid-state fermentation were conducted. The optimal temperature of the enzymes (lignin peroxidase, manganese peroxidase, xylanase, laccase, and cellulase) for degradation of lignocellulose by P. chrysosporium was found. We also measured the maximum activity of enzymes (lignin peroxidase 0.15 IU/mL, manganese peroxidase 0.90 IU/mL, laccase 0.11 IU/mL, cellulase 5.87 IU/mL, carboxymethyl cellulase 9.52 IU/mL, xylanase 1.16 IU/mL) used for the process. As a result, 4.73 mg/mL of reduced sugar was obtained and 61.02% of lignin was degraded by solid state fermentation of P. chrysosporium on spent coffee ground.

• The Plant Pathology Journal
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• 제29권4호
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• pp.451-453
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• 2013

Common root rot caused by Cochliobolus sativus is a serious disease of barley. A simple and reliable method for assessing this disease would enhance our capacity in identifying resistance sources and developing resistant barley cultivars. In searching for such a method, a conidial suspension of C. sativus was dropped onto sterilized elongated subcrown internodes and incubated in sandwich filter paper using polyethylene transparent envelopes. Initial disease symptoms were easily detected after 48h of inoculation. Highly significant correlation coefficients were found in each experiment (A, B and C) between sandwich filter paper and seedling assays, indicating that this testing procedure was reliable. The method presented facilitates a rapid pre-selection under uniform conditions which is of importance from a breeder's point of view.

• Mycobiology
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• 제35권2호
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• pp.72-75
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• 2007

Antifungal activity of 2-hydroxy 4,4'6'trimethoxy chalcone individually was tested against spore germination of ten fungi of different genera. Efficacy of the chemical was also tested against conidial germination and other growth parameters of Erysiphe pisi on excised pea leaves. 2-Hydroxy 4,4'6'trimethoxy chalcone inhibited spore germination at all the concentrations. Maximum inhibition was observed at 2000 ppm where more than 78 per cent inhibition of spore germination was observed in Ustilago cynodontis, Alternaria brassicicola, A. solani and Aspergillus flavus. It also reduced conidial germination of E. pisi significantly, when applied as pre-inoculation treatment.

• 식물병연구
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• 제20권2호
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• pp.101-106
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• 2014

감귤 궤양병은 Xanthomonas citri subsp. citri (Xcc)에 의해 발생하는 감귤에서 매우 중요한 병 중에 하나이다. 비록 한국에서 대부분 재배되는 감귤인 온주밀감은 감귤 궤양병에 대해 중도저항성이긴 하지만 지난 10년전 이래로 자주 발생되었다. 감귤에서 다른 병과 마찬가지로 감귤 궤양병도 포장에서 주로 화학농약에 의해 방제되고 있다. 농약의 부작용으로 인해 최근 다른 방제 수단이 요구되고 있다. 본 연구에서는 Xcc에 직접적인 항균 활성이 있는 식물근권세균 TRH423-3, MRL408-3, THJ609-3, TRH415-2을 선발하였다. 선발된 식물근권세균을 감귤 잎에 전 처리하였더니 감귤 궤양병균을 접종한 후 병 발생이 억제되었다. 유사하게, 포장 실험에서도 선발된 식물근권세균을 여러 차례 살포한 감귤나무에서 무처리한 나무에 비해 병이 적게 진전 되었다. 따라서 선발된 식물근권세균이 친환경 감귤농가에서 대체 수단으로 가치가 있다고 생각된다.

• 식물병연구
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• 제22권1호
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• pp.1-8
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• 2016

감귤 더뎅이병을 일으키는 E. fawcettii에 항균효과가 있는 식물근권세균 B. gladioli MRL408-3, TRH423-3, P. fluorescens THJ609-3, TRH415-2에 의해 감귤 더뎅이병이 감소하였다. 이들 식물근권세균을 전 처리한 Satsuma mandarin 감귤 잎에 감귤 더뎅이병균을 접종한 후 주사전자현미경을 이용하여 관찰하였다. 식물근권세균을 전 처리한 잎에서 무처리한 잎에 비해 감귤 더뎅이병의 병반수가 감소되었다. 특히 B. gladioli MRL408-3 균주를 전 처리한 식물에서 감귤 더뎅이병의 병반수가 뚜렷하게 억제되었다. 주사전자현미경을 통해 관찰 결과 식물근권세균을 전 처리한 감귤 잎 표면에서 병원균의 발아율과 발아관의 길이가 감소되는 것을 확인하였다. 시판 농약인 imibenconazole을 처리한 잎에서 감귤 더뎅이병균의 성장이 가장 뚜렷하게 억제되었는데, 이는 병반수가 가장 적게 형성된 것과 상통한다. 이들 결과를 통하여 식물근권세균에 의해 감귤 잎 표면에서 감귤 더뎅이병균의 발아와 생장이 억제되고 그 결과 감귤 더뎅이병의 발생이 감소되는 것으로 판단된다.

• 식물병연구
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• 제22권4호
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• pp.257-263
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• 2016

클로렐라는 광합성을 통해 독립적으로 생활할 수 있는 녹조류로서 작물의 생육촉진효과와 더불어 식물병 발생을 억제한다고 알려져 있다. 그러나 클로렐라에 의한 식물병 억제 기작에 대해서는 연구가 미흡한 실정이다. 본 연구에서 클로렐라 일종인 C. fusca의 현탁액을 오이 잎에 전처리하였을 때 오이탄저병 진전이 억제되는지 여부를 조사하였으며, C. fusca를 전처리한 오이 잎에서 오이탄저병 억제 기작을 알아보았다. 그 결과, 무처리한 잎에 비해 C. fusca를 전처리한 잎에서 C. orbiculare의 부착기 형성률이 뚜렷하게 감소하였다. 또한 접종 부위에서 발견된 포자수도 무처리한 잎에 비해 유의성 있게 감소하였다. 한편, 살균제 $Benomyl^{(R)}$을 전처리한 오이 잎에서도 C. orbiculare의 부착기 형성률이 크게 감소하였으며 포자수도 C. fusca를 전처리한 잎과 유사하게 감소되었다. 따라서 이들 결과를 통해 C. fusca 전처리에 의해 오이탄저병 발생이 억제되며 이는 C. fusca에 의한 식물잎 표면에서 생화학적 또는 구조적 작용으로 인한 C. orbiculare의 부착기 형성 감소가 그 원인 중 하나일 것이라고 생각된다.