• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1430-1437
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• 2016

This study was performed to investigate the changes in isoflavone composition, estrogenic activity and antiestrogenic activity of soybean cultivars of different isoflavone content (Aga 8, Uram, Cheongja 3, and Dawon) with germination. Total isoflavone contents of Aga 8, Dawon and Cheongja 3 was increased from 2,671.74, 261.08 and 2,240.08 to 2,977.50, 966.13 and $2,354.11{\mu}g/g$, respectively after germination except for Uram cultivars, and highest contents of total isoflavone showed $2,977.50{\mu}g/g$ and $2,354.11{\mu}g/g$, respectively in Aga 8 and Cheongja 3 after germination. MTT cell proliferation assay using MCF-7 cells revealed that germinated soybean of Aga 8 and Cheonja 3 obtained not only contained a high content of isoflavone but also had estrogenic activity. Estrogenic activity of Aga 8 and Cheongja 3 soybean extracts increased from 116.21% and 101.60% to 135.34% and 121.05% after germination. These results suggest that germinated soybean of Aga 8 and Cheongja 3 might have a potential preventive effect on estrogen-deficient diseases.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.343-354
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• 2014

Rice blast disease caused by Magnaporthe oryzae is one of the most serious diseases of cultivated rice (Oryza sativa L.) in most rice-growing regions of the world. In order to investigate early response genes in rice, we utilized the transcriptome analysis approach using a 300 K tilling microarray to rice leaves infected with compatible and incompatible M. oryzae strains. Prior to the microarray experiment, total RNA was validated by measuring the differential expression of rice defense-related marker genes (chitinase 2, barwin, PBZ1, and PR-10) by RT-PCR, and phytoalexins (sakuranetin and momilactone A) with HPLC. Microarray analysis revealed that 231 genes were up-regulated (>2 fold change, p < 0.05) in the incompatible interaction compared to the compatible one. Highly expressed genes were functionally characterized into metabolic processes and oxidation-reduction categories. The oxidative stress response was induced in both early and later infection stages. Biotic stress overview from MapMan analysis revealed that the phytohormone ethylene as well as signaling molecules jasmonic acid and salicylic acid is important for defense gene regulation. WRKY and Myb transcription factors were also involved in signal transduction processes. Additionally, receptor-like kinases were more likely associated with the defense response, and their expression patterns were validated by RT-PCR. Our results suggest that candidate genes, including receptor-like protein kinases, may play a key role in disease resistance against M. oryzae attack.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.488-498
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• 2017

The aim of this study was to identify volatile and agardiffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.16-21
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• 2011

Ginseng root rot caused by Cylindrocarpon destructans is one of the most destructive diseases of ginseng(Panax ginseng). We analyzed the features of the species through pathogenicity test and genetic diversity analysis of C. destructans in Korea, for its application as basic data to attempt for effective control. C. destructans isolated from rotted ginseng roots exhibited a variety of colonial colors on media. It was assumed that there may exist genetic diversity in the population by the diversity of pathogenicity among isolates observed when artificially inoculated into ginseng roots. Pathogenicity tests using ex vivo wound inoculation with agar mixture inoculation on ginseng roots were performed similar results as were observed appear to be useful for rapid pathogen inspection. According to RAPD analysis results, Korean C. destructans isolates formed a single genetic group which can be distinguished readily from closely related other fungi. C. destructans group was divided into two small groups. Therefore, we were able to confirm pathogenicity and genetic difference between the isolates in each of the groups of the pathogen.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.282-289
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• 2012

The root rot of pepper (Capsicum annuum L.) caused by Phytophthora capsici is one of the most important diseases affecting this crop worldwide. This work presents the evaluation of the capacity of Streptomyces griseus H7602 to protect pepper plants against Phytophthora capsici and establishes its role as a biocontrol agent. In this study, we isolated an actinomycete strain H7602 from rhizosphere soil, identified it as Streptomyces griseus by 16S rRNA analysis and demonstrated its antifungal activity against various plant pathogens including P. capsici. H7602 produced lytic emzymes such as chitinase, ${\beta}$-1,3-glucanase, lipase and protease. In addition, crude extract from H7602 also exhibited destructive activity toward P. capsici hyphae. In the pot trial, results showed the protective effect of H7602 against pepper from P. capsici. Application of H7602 culture suspension reduced 47.35% of root mortality and enhanced growth of pepper plants for 56.37% in fresh root and 17.56% g in fresh shoot as compared to control, resulting in greater protection to pepper plants against P. capsici infestation. Additionally, the enzymatic activities, chitinase and ${\beta}$-1,3-glucanase, were higher in rhizosphere soil and roots of pepper plants treated with H7602 than other treated plants. Therefore, our results indicated a clear potential of S. griseus H7602 to be used for biocontrol of root rot disease caused by P. capsici in pepper.

• The Korean Journal of Pesticide Science
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• v.18 no.2
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• pp.104-114
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• 2014

Scale insects heavily damaged many agricultural crops and trees in urban and forest areas. This study was conducted to carry out alternative control methods for environmentally friendly control of scale insects. Hot water extract of Quisquali indica produced high mortality against the black pine bast scale, Matsucoccus thunbergianae in previously experiment. Methanol extract obtained from fruit of Q. indica was successively fractionated using hexane, chloroform, ethyl acetate, buthanol and water which were examined by exposing for their insecticidal activity against four Cocoidea species (Eriococcus lagerstroemiae, Ceroplastes japonicus, Crisicoccus pini and Planococcus citri) in laboratory. Hexane fraction gave the highest insecticidal activity against scale insect pest. GC-mass analysis confirmed that the main compounds of Q. indica were alpha-pinene, methyl palmitate, eugenol, methyl myristate, phthalic acid mono(2-ethylhexyl)ester and palmitic acid. Among those compounds, ${\alpha}$-pinene was included 10 hexane subfractions. $LC_{50}$ of ${\alpha}$-pinene was 0.0114 ppm against 2nd instar of E. lagerstroemiae. These results suggest that Q. indica extracts might be used as an alternative control agent of scale insects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.919-927
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• 2011

Avocado (Persea americana Mill., Family Lauraceae) is an important subtropical crop in the Americas where it has been cultivated for several thousand years. To investigate the bioactivities of avocado, which acts on bone formation, we prepared methanol extracts from the sarcocarp, peels, and seeds of avocado. The methanol extracts of peels and seeds showed higher bone-forming activity than avocado sarcocarp extracts accompanied by MC3T3-E1 osteoblast proliferation and alkaline phosphatase (ALP) activity. Additionally, the extracts of sarcocarp and peel from avocado also decreased tartrate-resistant acid phosphatase (TRAP) activity against differentiation of osteoclasts, derived from mouse bone marrow macrophages. The hexane fraction from avocado peels showed strong bone-forming activity accompanied by osteoblast proliferation and ALP activity (170.7${\pm}$8.4%), and the ethyl acetate fraction from avocado peel decreased TRAP activity (5.2${\pm}$0.3%) and differentiated osteoclasts at 50 ${\mu}g$/mL. Therefore, avocado is expected to be a natural source for developing medicinal agents to prevent bone-related diseases, such as osteoporosis, by increasing osteoblast differentiation and reducing osteoclast activity.

• Research in Plant Disease
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• v.13 no.3
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• pp.164-169
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• 2007

Three kinds of disease occurring on ginseng leaves, such as grey mold, Alternaria blight, and anthracnose, started at the beginning of June, July, and August, respectively. The disease incidence was rapidly increased from the beginning of rainy season. To develop the control system with fungicides, 6 fungicides were selected and applied on ginseng at the indicated time. Calculating the control value by using the area under the disease progressing curve (AUDPC), the control activities of the supervised control system with fungicides were 61.7, 78.8 and 70.5% against grey mold, Alternaria blight, and anthracnose, respectively. The application of the mixture of carbendazim and diethofencarb on first of June was very important in control system with fungicides. If it was deleted in control system, control value was decreased against grey mold. In the case of Alternaria blight and anthracnose, the application of difenoconazole on July 18, and trifloxystrobin on August 7 were indispensible. If difenoconazole and trifloxystrobin were not applied on July 18, and August 7, the control activities against Alternaria blight and anthracnose, respectively, were decreased to 28.9% and 44.4%.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.3
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• pp.267-274
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• 2017

Recently, several researches have been studied on agricultural automation system according to convergence of IT technology with agriculture. An automatic control system of the growth environment in crops is one of the these researches. The controls of damages caused by diseases and insects pest in crops are mainly carried out by manual mode or semi-automatic mode because of farmer's concerns for poor efficiency. But, this situation needs to be improved because it occurs various problems, such as human exposure to toxic pesticides, environmental pollution and waste due to drug overuse. In order to solve these problems, we developed an automatic quantity control system which based on the amount of pesticides for area under cultivation. The amount of pesticides is calculated according to the manufacturer's instruction for pesticides. To verify the effectiveness of our developed automatic system, we also compared with the systems of manual mode and the semi-automatic mode. The experimental results of a pest control performance of an automatic quantity control system showed that automatic system can reduce overuse of drugs. These results suggested that it can be expected to replace the existing system, with equivalent effectiveness to the manual mode.

• Research in Plant Disease
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• v.19 no.2
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• pp.95-101
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• 2013

Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is one of the most serious diseases of crucifers world-wide. To establish the efficient screening method for resistant cabbage to Xcc, different inoculation methods, inoculation positions, growth stages of seedlings, and incubation temperatures after inoculation were investigated with the seven cabbage cultivars showing different resistance degrees to the pathogen. Clipping with mouse-tooth forceps was better inoculation method than piercing with 18 pins or cutting with scissors to distinguish the level of resistance and susceptibility. In inoculation using mouth-tooth forceps, clipping the edges of the leaves near veins is more effective than injuring the veins of the leaves directly. In addition, the inoculated plants kept at $22^{\circ}C$ showed more clear resistant and susceptible responses than those kept at 26 or $30^{\circ}C$. On the basis of the results, we suggest that an efficient screening method for resistance of cabbage cultivars to black rot is to clip the edges of the leaves near veins of the four-week-old seedlings with mouth-tooth forceps dipped in a suspension of Xcc at a concentration of $7{\times}10^7$ cfu/ml and incubate the inoculated plants in a growth room at $22^{\circ}C$ with 12-hr light a day.