• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.897-909
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• 2015

This study was conducted to evaluate the effect of weed control on disease incidence, plant growth and fruit quality, and to provide effective method to farmers at the vineyard. At the raincoat greenhouse cultivating 'Campbell Early', several weed controlling methods were compared to the control. Mean temperature of plots between soil covering (C.B., W.F., S.N., P.F. and R.H.) and non soil covering (M.W.2, M.W.3 and U.T.) were similar with $26.2^{\circ}C$ (July) and $25.8^{\circ}C$ (Aug.), but humidity of soil covering was sharply decreased in late-July under 40%. Soil water were all higher in soil covering plots than that of non-soil covering, however, soil temperature was recorded lower in soil covering plots. Disease incidence of Peudocercospora vitis according to soil coverings had effect on black plastic film mulching by decreasing grapevine leaf spot to 85% in July, 69% in August, compared to the control, with showing the smallest lesion incidence in FMB. Among growth characters, internode length and internode width of black plastic film mulching was higher than that of the control. SPAD value of black plastic film mulching was recorded the highest. It was not significant among the treatments, but brix was recorded highly in black plastic film mulching with $14{\sim}15^{\circ}Brix$.

• Mycobiology
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• v.30 no.2
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• pp.61-64
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• 2002

A Monokaryotic strain G8M without clamp connections was isolated from germinated basidiospore that was obtained from cultivated fruit body. Strain G8M was used as a tester isolate for 'dikaryon-monokaryon mating'(di-mon mating) with the strains of Ganoderma lucidum, G6 and G35(Korean wild strains), G3(Taiwan), G4(Canada), G15(America), G. oregonense G24, G. resinaceum G28, G. oerstedii G23, and G. subamboinense G29. Isolate G8M was compatible to Korean strains G6 and G35, but was incompatible to foreign strains G3, G4, or G15. Compatible reactions between strains were readily observed macroscopically. Clear barrage lines formed between incompatible strains. These clear lines were not apparent in compatible di-mon matings. The Korean strains were morphologically distinct; they did not form any chlamydospores, and stopped growth at $35^{\circ}C$. The strains of G. lucidum from Korea may be considered as different species from Taiwan, Canadian and American cultures.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.258-263
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• 2015

This study was conducted to evaluate the effects of the fog-cooling system on the growth and yield characteristics of two large-fruited paprika cultivars during summer cultivation season. The temperature inside the greenhouse equipped with fog-cooling system was $2-3^{\circ}C$ lower than that in the control. The results of study show the possibilities of maintaining indoor temperatures below $35^{\circ}C$ and relative humidity at the level of 80% using fogcooling system during hot seasons of the year. Plant height, fruit weight and number of fruits per plant were higher for both cultivars in the fog-cooling treatment compared to those in control. Mean fruit weight and yield per unit area were higher in the fog-cooling treatment than those in the control. However there were no significant differences in sugar content, flesh thickness and locule number of fruits due to fog-cooling system. Number of fruits with epidermal cracking was decreased in the fog-cooling system for both paprika cultivars. Mineral contents of plants such as nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), were not affected due to fog-cooling treatment.

• Journal of Bio-Environment Control
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• v.3 no.2
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• pp.119-127
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• 1994

This study was conducted to investigate the effects of temperature and light conditions on the vigor and growth responses of red pepper(Capsicum annuum L.) seedlings in the nonheated plastic houses with triple and quadruple coverings during winter. The results obtained were as follows ; 1. The growth in terms of plant height, number of leaves, leaf area and dry weight of each organ was reduced up to 50% in the triple coverings compared to quadruple ones. The greatest difference between the triple coverings and quadruple ones was the leaf area, showing two to five times larger in the quadruple ones. Therefore, the differences of the early environmental conditions during raising seedling stage was well reflected. 2. The leaf expansion in the early stage of seedling was delayed in the triple coverings and subsequently crop growth rate(CGR) significantly reduced. The specific leaf area (SLA) in the triple coverings was less than quadruple ones. The net assimilation rate (NAR) was increased in the early stage of seedlings and then reduced in the quadruple coverings. In triple ones, however, the great reduction showed at six weeks after sowing and then increased sharply. 3. The linear relationship among leaf area, total dry weight and leaf dry weight was observed in the all experimental areas, while between leaf area and crop growth rate only in the quadruple coverings, and between leaf area and net assimilation rate in both triple and quadruple ones. 4. The dry matter partitioned to the leaf increased up to six weeks after sowing in the triple coverings but reduced in the stem and root. However, the adverse results were obtained in the quadruple ones. 5. In the triple coverings, the number of branches showed the exponential increment while fruit weight showed linear increment in both triple and quadruple ones. Higher yield was obtained in the quadruple ones. 6. The shoot dry weight among the characteristics of seedlings was greatly contributed to the yield of red pepper after transplanting. Accordingly, one of the decisive criterion for good quality of red pepper seedlings was determined by the highest correlation between shoot dry weight of growing plant and fruit yield of pepper plant.

• Journal of Bio-Environment Control
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• v.5 no.1
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• pp.65-70
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• 1996

Water potential which is an physical chemistry and thermodynamic indicator expressed water status of plant root, stem and fruit could be use as a useful indicator for growth control of hydroponically grown muskmelon plant. Linear relationship was observed between EC and water potential of nutrient solution, consequently increment of EC related to the decreasing water potential and resulted with the alteration of water potential and solute potential of upper leaves. Rapid reduction in growth was observed in over 5${\mu}{\textrm}{m}$ of Cu concentration in the media and same tendency was recorded in the shoot fresh weight, root dry weight and chlorophyll content. Increment of Cu concentration in the nutrient solution leads to lower the growth rate and then the water potential of upper leaves. Turgor pressure was not affected the growth of hydroponically grown muskmelon and also Cu concentration of nutrient solution was not recognized the direct relationship to the growth characteristics of muskmelon. These results demonstrated that water potential of nutrient solution can be use as an useful indicator for water physiological comparison of plant growth in hydroponically grown muskmelon.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.574-579
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• 2010

Waste nutrient solution (WNS) that was the drained nutrient solution of Horticultural Research Institute of Japan for culture tomato in perlite hydroponics showed $1.9-2.4dS{\cdot}m^{-1}$ of EC and 5.7-7.1 pH from April to July. Although ${NH_4}^+-N$ concentration of WNS decreased remarkably, the other nutrients did not change significantly, as compared with supplied solution. There were no significant differences in plant height, stem diameter, and the other growth characteristics of tomato plants grown by 2 fertigation nutrient solutions; BHF (Bountiful Harvest Fertilizer, 10% of N, 13% of $PO_4$, 13% of K, 0.05% of B, 0.05% of Zn, and 0.0023% of Cu that made in Korea) and Megasol (11% of N, 8% of $PO_4$, 34% of K, 0.032% of Mn, 0.002% of B, 0.048% of Fe, 0.0122% of Zn, and 0.0023% of Cu that made in Belgium.); however, the chlorophyll content of tomato leaf was highest in WNS. The fresh and dry weight of tomato plants were higher in 3 fertigation treatments than irrigation of tap water, while there were no significant differences in fresh and dry weight among the 3 fertigation treatments. The mineral content of tomato leaf also did not show any differences among the 3 fertigation treatments and any regular tendency in all minerals. Total yield, fruit weight and fruit numbers of tomato were higher in WNS, followed by Megasol, BHF and control, although there were not any difference among the 3 fertigation nutrient solution treatments. BER(blossom-end rot)of tomato fruits decreased in fertigation treatments, especially, fruits grown in WNS and BHF showed lower BER. However, the transpiration rate of leaf was higher in control, followed by BHF, WNS and Megasol, The fruit size and soluble solids content was higher in 3 fertigation nutrient treatments than control. These results suggest that WNS can be used for fertigation solution in tomato because yield and quality of tomato fruit grown in WNS fertigation treatment were similar to those in 2 fertigation nutrient solutions treatments(BHF, Megasol).

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.312-321
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• 2014

Tricholoma bakamatsutake is one of the edible ectomycorrhizal mushrooms as an allied species of Tricholoma matsutake. This is the first report on physical characteristics of T. bakamatsutake strains collected from Quercus mongolica forests in Korea. The pure cultures of these strains were isolated from the tissues of fruit bodies and the culture characteristics were investigated under different conditions (media, temperatures, nitrogen sources). Most strains showed the highest mycelial growth on potato dextrose agar (PDA) at 20 or $25^{\circ}C$. Two strains of T. bakamatsutake preferred the ammonium-form rather than the nitrate-form as an inorganic nitrogen source. T. bakamatsutake showed significantly slower mycelial growth when compared with T. matsutake from a Korean forest, although the optimum culture conditions for the two allied species were similar. We also tested the ability to form mycorrhizae as well as cellulase activity of T. bakamatsutake. All strains showed cellulase activity on a carboxymethylcellulose (CMC) agar plate. The mycorrhizae on axenic Pinus densiflora seedlings were formed by two strains of T. bakamatsutake after 3 or 8 months of inoculation. P. densiflora seedlings inoculated with T. bakamatsutake had a much higher biomass than un-inoculated seedlings.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.51-58
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• 2013

Emerging studies suggest that vegetables or fruit juices deemed to be potential alternative base medium for lactic acid bacteria fermentation. Until now, limited studies have been carried out to evaluate such applications. Thus, the objective of present study is that lactic acid bacteria were evaluated for their viability at low pH, growth during storage at low temperature, and $CO_2$ formation. Furthermore, the effects of grapefruit extract with respect to cell viability, sensory ability, and organic acid production were evaluated for these strains. The probiotic properties of the strains, including acid tolerance, bile tolerance, and adhesion to human intestinal epithelial cells (HT-29 cells), prebiotic characteristics, and safety features were examined. All strains survived in MRS medium broth adjusted to pH 3.8, at $10^{\circ}C$ for 6 days, and did not produce $CO_2$ to check post fermentation. The medium of grapefruit extract fermentation by Lactobacillus plantarum CJIH 203 resulted in maximal viable counts, compared with other strains, and the extract subsequently tasted sour due to the presence of lactic acid. Lactobacillus plantarum CJIH203 was highly resistant to artificial gastric juice and intestinal juice, while Lactococcus lactis SJ09 strongly adhered to HT-29 cells. Tagatose showed the greatest ability to enhance the growth of L. plantarum SJ21, relative to the other strains. All strains were verified by safety tests such as hemolysis, gelatin hydration, and urea degradation. Therefore, these strains could be promising candidates for use in reducing excessive post-fermentation and functional products.

• The Plant Pathology Journal
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• v.39 no.3
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• pp.275-289
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• 2023

Fungal isolates from infected Chinese quince trees were found to cause black rot in Yeongcheon, Gyeongsangbuk Province, Korea. The quince leaves withered and turned reddish-brown and fruits underwent black mummification. To elucidate the cause of these symptoms, the pathogen was isolated from infected leaf and fruit tissues on potato dextrose agar and Levan media. Several fungal colonies forming a fluffy white or dark gray mycelium and two types of fungi forming an aerial white mycelium, growing widely at the edges, were isolated. Microscopic observations, investigation of fungal growth characteristics on various media, and molecular identification using an internal transcribed spacer, β-tubulin, and translation elongation factor 1-α genes were performed. The fungal pathogens were identified as Diplodia parva and Diplodia crataegicola. Pathogenicity tests revealed that the pathogen-inoculated fruits exhibited a layered pattern, turning brown rotting; leaves showed circular brown necrotic lesions. The developed symptoms were similar to those observed in the field. Fungal pathogens were reisolated to fulfill Koch's postulates. Apples were inoculated with fungal pathogens to investigate the host range. Strong pathogenicity was evident in the fruits, with browning and rotting symptoms 3 days after inoculation. To determine pathogen control, a fungicidal sensitivity test was conducted using four registered fungicides. Thiophanate-methyl, propineb, and tebuconazole inhibited the mycelial growth of pathogens. To the best of our knowledge, this is the first report on the isolation and identification of the fungal pathogens D. parva and D. crataegicola from infected fruits and leaves of Chinese quince, causing black rot disease in Korea.

• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.67-73
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• 2002

This study was conducted to investigate the effect of organic agricultural materials, chitosan and wood vinegar, on the growth and yield of red pepper and soil microflora. In the chitosan treatments, the density of actinomycetes in soils increased, while the density of fungi decreased. Compared with the conventional cultivation, the stem diameter of red pepper was greater in the chitosan or wood vinegar experimental plots at 50 days after transplanting, though there was no difference in chlorophyll content among treatments. The incidence of disease and insect was higher in the treatments of organic agricultural materials than the conventional cultivation, regardless of application frequency. Contents of cations such as Ca and K in leaves and fruits increased by chitosan treatment. In all experimental plots, fruit yield decreased because of diseases and insects. But in chitosan treatment plot with 10 times of application, characteristics of fruits were superior to others and the yield index of red pepper was the highest as 92.4% as compared to the conventional cultivation.