• Journal of Life Science
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• v.24 no.11
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• pp.1187-1192
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• 2014

Pepper, consumed as a typical spice food around world, is mainly cultivated in warm countries, including Korea, China, and Mexico. Phytophthora capsici is a pathogen on several economically important crops, including pepper. The oomycete attacks the roots, stems, leaves, and fruit of the host plants. To understand the molecular mechanisms underlying development of the disease, the genes expressed during pepper-P. capsici interaction were explored by analyzing expressed sequence tags (ESTs). A cDNA library was constructed from total RNA extracted from pepper leaves challenged with P. capsici for three days, resulting in an early stage of symptom development for comparable interaction. A comprehensive analysis of single-pass sequencing of 5,760 randomly selected cDNA clones extracted 5,148 high-quality entries for contig assembly, which generated 2,990 unigenes. A homology search of the unigenes with BLASTX resulted in 2,409 matches, of which 606 showed classified functional catalogs.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.201-209
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• 2006

Antifungal activities of 43 different plant oils were evaluated against different phytopathogenic fungi. Thyme oil showed highest antifungal activity among the tested oils. The major of thyme oil were found to be thymol, carvacrol, bomeol, p-cymene and linalool. Thymol and carvacrol were found to be responsible for thyme's antifungal activity. The spore germination assay was conducted on Alternaria mail and Botrytis cinerea. Thymol and carvacrol strongly inhibited spore germination in the fungi test. In addition, thymol and carvacrol showed a curative effectiveness to gray mold disease on cucumber crop. The antifungal activities of alkylphenol and alkylaniline compounds, which has similar molecular structure to that of thymol or cavacrol, were also tested. It was found that alkylphenol compounds also show higher inhibition to spore germination. Thus, thymol, carvacrol and alkylphenol compounds can be used an potent antifungal agents.

• The Korean Journal of Mycology
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• v.16 no.2
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• pp.60-63
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• 1988

Each of 103 isolates of Phytophthora capsici was obtained from diseased red pepper plants randomly belonged to either the mating type $A_1$ or the mating type $A_2$. Fifty four isolates were classified as mating type $A_1$, and 49 isolates were classified as mating type $A_2$.Oospores were formed in each combination of isolates between $A_1$ or $A_2$ on 5% V-8 juice agar except one combination.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.235-241
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• 2003

For the biological control of Phytophthora blight of red-pepper caused by Phytophthora capsici, an antibiotic-producing plant growth promoting rhizobacteria (PGPR) Bacillus sp. KL 39 was selected from a local soil of Kyongbuk, Korea. The strain KL 39 was identified as Bacillus megaterium by various cultural, biochemical test and API and Microlog system. B. megaterium KL 39 could produce the highest antifungal antibiotic after 40 h of incubation under the optimal medium which was 0.4% fructose, 0.3% yeast extract, and 5 mM KCl at 30 C with initial pH 8.0. The antifungal antibiotic KL 39 was purified by Diaion HP-20 column, silica gel column, Sephadex LH-20 column, and HPLC. Its RF value was confirmed 0.32 by thin-layer chromatography with Ethanol:Ammonia:Water = 8:1:1. The crude antibiotic KL39 was active against a broad range of plant pathogenic fungi, Rhizoctonia solani, Pyricularia oryzae, Monilinia fructicola, Botrytis cinenea, Alteranria kikuchiana, Fusarium oxysporum and Fusarium solani. The purified antifungal antibiotic KL39 had a powerful biocontrol activity against red-pepper phytophthora blight disease with in vivo pot test as well as the strain B. megaterium KL 39.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.619-624
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• 1992

Tn5 lac 삽입으로 채소입고병원균에 길항력이 약화된 T-67 및 고추역병균과 참깨역병균에 길항력이 약화된 T-81의 Tn5 lac 유전자 일부와 오른쪽 말단에 있는 길항관련 유전자의 flanking sequence가 cloning된 pAG67 및 pAG81 clone을 선발하였고, pAG67 및 pAG81 clone된 길항관련 유전자의 flanking sequence를 야생 길항균 Pseudomonas maltophilia B-14의 DNA를 probe로 사용하여 Southern hybridization으로 확인하였으며, 제한효소 지도를 작성하여 8Kb 및 4Kb 크기의 flanking sequence가 cloning되었음을 확인하였다. pAG6 및 pAG81의 flanking sequence를 EcoRi-BglII와 EcoRI-MpaI으로 분리하여 유전자 은행으로부터 길항관련 유전자가 cloning된 cosmid clone 7개주를 선발하였다.

• Research in Plant Disease
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• v.16 no.2
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• pp.158-162
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• 2010

Four promising biocontrol agents against Phytophthora capsici were selected from 507 bacterial isolates collected from rhizosphere soils and roots of pepper plants. In vitro experiment, these four biocontrol agents inhibited mycelial growth, germination of cystospores, and formation of zoosporangia and zoospores of Phytophthora capsici. In the pot experiment, the four biocontrol agents showed control efficiency higher than 70%. In greenhouse experiment, the isolates G28-6 gave the control value of 79.4%. These four biocontrol agents successfully colonized in the population density beyond 105 cfu/g on roots of pepper in vitro. The isolates G28-6 was identified as Pseudomonas aurantiaca, based on its cultural, morphological, and biochemical characterization and 16S rRNA gene sequence analysis.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.186-193
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• 2001

A powerful antagonistic bacterium against Phytophthora capsici causing phytophthora blight of red pepper was isolated from the cultivated soil in Kyongju Korea, The bilogical control mechanisms of the isolated strain were caused by strong antifungal antibiotic, siderophore and cellulase. The strain was identified as Chryseomonas luteola by the cultural morphological and physiological characteristics. The opti- mal culture medium for the antibiotic production was determined as follows : 0.15%D(+) cellobiose, 0.55% $NH_4$CI, 0.01% KCI 0.7% $K_2$$HPO_4$ 0.2% $KH_2$PO$_4$ and 0.5% sodium citrate at pH 7.0 The optimal incubation time was 84 hours at $30^{\circ}C$ In pot bioassay, the treatment of C luteola 5042 protected red pepper plant against the blight of Phytophthora capsici.

• Journal of Mushroom
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• v.19 no.4
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• pp.272-278
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• 2021

Bacillus velezensis HKB-1 was isolated from the composted spent mushroom substrate of Lentinula edodes (LeCSMS) and inhibited mycelial growth of phytopathogenic fungal species, Phythhopthora capsici, Collectotrichum coccodes and Fusarium oxysporium by more than 70%. B. velezensis HKB-1 showed bacterial growth rate 10 to 100 times higher than that of other commercial bacterial media in water extract of LeCSMS supplemented with 1% molasses. The LeCSMS medium was effective in promoting the growth of pepper and controlling Phytophthora blight disease of pepper.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.311-317
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• 2006

Using PCR amplification, we cloned a cellulase gene (ce/H) from the Bacillus subtilis AH18 which has plant growth-promoting activity and antagonistic ability against pepper blight caused by Phytophthora capsici. The 1.6 kb PCR fragment contained the full sequence of the cellulase gene and the 1,582 bp gene deduced a 508 amino acid sequence. Similarity search in protein database revealed that the cellulase of B. subtilis AH18 was more than 98% homologous in the amino acid sequence to those of several major Bacillus spp. The ce/H was expressed in E. coli under an IPTG inducible lac promoter on the vector, had apparent molecular weight of about 55 kDa upon CMC-SDS-PAGE analysis. Partially purified cellulase had not only cellulolytic activity toward carboxymethyl-cellulose (CMC) but also insoluble cellulose, such as Avicel and filter paper (Whatman No. 1). In addition, the cellulase could degrade a fungal cell wall of Phytophthora capsici. The optimum pH and temperature of the ce/H coded cellulase were determined to be pH 5.0 and $50^{\circ}C$. The enzyme activity was activated by $AgNO_3$ or $CoCl_2$. However its activity was Inhibited by $HgC1_2$. The enzyme activity was activated by hydroxy urea or sodium azide and inhibited by CDTA or EDTA. The results indicate that the cellulase gene, ce/H is an antifungal mechanism of B. subtilis AH18 against phytophthora blight disease in red-pepper.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.303-308
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• 1994

We have obtained following results by executing this experiment to define effects of organic substances applied and temperature on fungistatic effect which is regarded as basic factor of inhibition against hot-pepper blight affection : 1. Fungistatic effect of soil on Phytophthora capsici is enlarged by application of organic material such as rice straw rather than matured composts. Morever, it is confirmed that fungistatic efect is more eminent at the temperature of $15^{\circ}C$ and $5^{\circ}C$ than at $30^{\circ}C$, Degree of fungistatic effect of soil tends to decrease as the goe on from the moment of using organic substance generally, in soil applied as the goes on from the moment of using organic substance generally, in soil applied rice straw it is prove that fungistatic effect is maintained stably in a long term. 2. Effect of applicating organic substances and treating by temperature on production of zoosporangium of Phytophthra capsici is reviewed. In case that sterilized soil solution is added on cultured hypae of Phytophthra capsici, increase in the production of zoosporangium is found which is statistically significant(at degree of 1%), while decrease effect statistically significant is found in case of adding soil solution used for applying bark compost. However, defferences between treatments of temperature is not found. On the other hand, when nonsterilized soil solution is added, significant defference between types of organic substance is not found, while significant difference is found between treatments of temperature, therefore formation of zoosporangium is increased at the condition of $5^{\circ}C$ comparing to that of $30^{\circ}C$. 3. Putting above result of examination concerning to composition of soil microrganisms in each treated soil and to fungistatic effect of them, it seems that fungi and bacteria in soil is mostly related to fungistatic activity of soil.