• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.44 no.4
• /
• pp.294-303
• /
• 2008

Squid jigging fishery is very important in that there are about 1,000 jigging vessels more than 10 tonnage and about 5,000 ones less than 10 tonnage in Korea. But the cost of oil which is used to light fishing lamps, goes significantly up to almost one hundred million won for 50 tonnage vessels and forty million won in case of vessels less than 10 tonnage. This cost has almost taken 40% of total fishing costs. That is, the fishing business condition of squid jigging fishery is recently in the very difficult situation. As oil price increases, the business condition of the fishery gets worse and worse. Therefore it is very urgent to develop an economical fishing lamp, to solve this problem of fishery's business difficulty. This research aims at developing a fishing lamp for squid jigging fishery using the light emitting diode which has very excellent efficiency and durability. We made a water tank with 20 meters width which is a shape of raceway to research behavioral characteristics of Japanese flying squid to LED light, and made an experiment to investigate optimum wave of LED light to lure squid. The method is to establish LED lamps on both ends of water tank and to observe squid's behavior. Colors and wave lengths of LED lamps, used in experiment, are red(634nm), yellow(596nm), green(523nm), blue(454nm) and white(454nm+560nm). In experiment for attractive capability of LED lamp to squids, Japanese flying squid are highly attracted to blue lamp and white lamp. However, they are dispersed to red and yellow lamps. In addition, Japanese flying squid have moved and stayed in both dark ends of water tank. When compared intermittent lamp with continuous lamp, Japanese flying squid are highly attracted to intermittent lamp when intermittent interval is 0.25 second.

• The Korean Journal of Mycology
• /
• v.29 no.1
• /
• pp.34-40
• /
• 2001

RAPD test and the observation of morphological, cultural characteristics of fourteen selected entomogenous fungi were conducted to investigate the analysis of their internal relationships. Paecilomyces tenuipes showed snow flower form attached to numerous white conidiophores, produced globular and semi-egg types on the club types of phialides. Cordyceps militaris formed globosely conidiophores, dark yellow fruiting body on pupa. The phialide as on Acremonium-type in global conidiophores. Beauveria bassiana covered with conidia was not formed fruiting body and adhered conidia on conidiophore of zigzag type. The PDA and SDAY medium were confirmed as an optimum growth of them. P. tenuipes showed to velvet and plane types in several media whereas C. militaris was belong to centrally raised and floccose in the morphological type. In contrast, B. bassiana covered with conidia on velvet shape. The size of amplified products were analyzed by RAPD using URP primer and were from 100 bp to 2.0 kb with $10{\sim}14$ geuomic DNA. Total similarities of two groups were by dendrogram of UPGMA analysis. The homology of P. tenuipes groups was 94.8 to 100%. It also showed 70.1 to 96.6% in C. militaris group and B. bassiana was higher similarity than any other. The internal change of C. militaris, produced telemorph fruiting body, was higher seperated in species than P. tenuipes and B. bassiana in the RAPD.

• The Korean Journal of Mycology
• /
• v.39 no.1
• /
• pp.39-43
• /
• 2011

A new cultivar "Dan Bi" of Pleurotus eryngii was developed by the method of mono-mono crossing between monokaryotic strains derived from KNR2312 and KNR2596. The parental strains, KNR2312 and KNR2596, are characterized by the property of high quality and a small number of primordia formation, respectively. The optimum temperature of mycelial growth was 25 and that of fruiting body development was $15{\sim}16^{\circ}C$. The period of harvesting including primordia formation was 0.7~1.3 days later than that of control strain Knneutari No. 3 in the culling cultivation. The color of pileus and stipe surface was neutral-brown and pure white, respectively. The shape of pileus was dome and has a scale like as cobweb. The yield was $93{\pm}9.7$ g per 850 cc of plastic bottle. Analysis of the genetic characteristics of the new commercial variety "Dan Bi" showed a different profile as that of the control strain, Knneutari No. 3, when RAPD (Random Amplified Polymorphic DNA) primer #8005 was used. This new variety "Dan Bi" of Pleurotus eryngii is characterized by a small number of primordia formation after scratching.

• The Korean Journal of Mycology
• /
• v.45 no.3
• /
• pp.246-250
• /
• 2017

Sclerotium rot was observed on mungbean (Phaseolus radiatus L.) plants cultivated in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services in September 2015. The progression of rot was initially observed as water-soaked lesions on several parts of the affected plant. Severely infected plants were blighted and eventually died. White mycelial mats spread over the lesions and numerous sclerotia formed on stems near the soil line. The sclerotia were globoid in shape, 1~3 mm in size, and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$ and the hyphal width was $4{\sim}8{\mu}m$. Typical clamp connections were observed on the hyphae of fungus grown on PDA. For molecular identification, the complete internal transcribed spacer (ITS) ribosomal DNA (rDNA) of the causal fungus was sequenced and analyzed. Based on the mycological characteristics, ITS rDNA sequence analysis, and pathogenicity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report of Sclerotium rot on mungbean caused by S. rolfsii in Korea.

• Applied Biological Chemistry
• /
• v.46 no.1
• /
• pp.46-49
• /
• 2003

Paddy and milled rice quality, milling characteristics, energy consumption of milling process were investigated using Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo varieties. Thousand grains weights of the varieties dried to 15% moisture content were 22.92-28.60 g, with Dasanbyeo being the heaviest. Optimum clearance of rubber roller for obtaining maximum dehulling recovery was 30% of each rice variety thickness. At that time, perfect brown rice ratios of Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo were 95.24%, 98.86%, 95.97%, 97.75%, and 97.31%, respectively, and showed no significant differences among varieties. Ratios of removed rice bran after two times milling ranged 70.93-91.38%, with Dasanbyeo showing the highest ratio, and the average head rice ratio was 92.87%.

• The Korean Journal of Mycology
• /
• v.30 no.2
• /
• pp.173-175
• /
• 2002

Sooty leaf blight was found on Dendrobium sp. in several farmers' fields located in Namji-eup, Changnyeong-gun, Gyeongnam province, Korea in 2001. Symptoms of the disease appeared on leaves. Sooty leaf spots were started with amphigenous, subeircular to irregular spots, with light grayish brown to black color with definite margin lines on the upper surface of leaves. Infected leaves became defoliated and whole plants eventually were died. The infection rates of the disease in the surveyed area reached up to 64.8%, in the early September. Conidiophores of the causal fungus were dark grayish brown in color, densely fasciculate, straight, curved to sinuous, branched, $5{\sim}10$ septate and $63{\sim}164{\times}3.2{\sim}4.9{\mu}m$ in size. Conidia were pale to olivaceous in color, obclavatecylindric, straight to slightly curved in shape, $1{\sim}5$ septate and $46{\sim}98{\times}3.2{\sim}3.9{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus was $25^{\circ}C$. The fungus was identified as Pseudocercospora dendrobii on the basis of its mycological characteristics. This is the first report on sooty leaf light of Dendrobium sp. caused by Pseudocercospora dendrobii in Korea.

• The Korean Journal of Mycology
• /
• v.27 no.1 s.88
• /
• pp.32-38
• /
• 1999

A Saprolegnia sp. was isolated from cultured snakehead, Channa argus, and its physiological characteristics were investigated. The optimum temperature, pH and NaCl concentration for mycelial growth of Saprolegnia sp. were $25^{\circ}C$, 6.0 and 0%, respectively. The mycelial growth was increased with the addition of 10 mM phosphate and 10mg/L casamino acid. The essential oils extracted from three plants, Artemisia princeps var. orientalis, Thuja orientalis and Chamaecyparis obtusa have been tested to know whether they inhibit the growth of Saprolegnia sp. at six different oil concentrations(10, 100, 500, 1,000, 1,500 and 2,000 ppm). Essential oil from A. princeps var. orientalis began to inhibite the mycelial growth of Saprolegnia sp. at the concentration more than 10ppm. Using other essential oils from T. orientalis and C. obtusa, those initially inhibited the mycelial growth of Saprolegnia sp. at the concentration over 10 ppm and complate inhibition of mycelial growth was observed at over 500 ppm. The histopathological features of Snakehead infected by Saprolegnia sp. were studied. A club shape of gill lamella epithelial cells was observed in the gill. The mycelial cells were penetrated into muscular tissue, and the accumulation of the ceroid was observed in the liver, spleen and kideny tissue in common. The necrosis of tubular epithelial cells was seen in the liver tissue, parenchymal tissue in the spleen and tubular epithelial cells in the kidney.

• The Korean Journal of Mycology
• /
• v.36 no.1
• /
• pp.58-62
• /
• 2008

'Miso', a new variety of oyster mushroom was developed for the bottle culture at the Chungnam Agricultural Research & Extension Services. Its mycelium grew rapidly with $8.4{\sim}8.6\;mm/day $ at $25{\sim}28^{\circ}C$ on PDA medium. The optimum pH of the mycelial growth was pH 5.0. It took 24 days for the primitive primordium formation after inoculation on pine sawdust media mixed with 20% wheat bran. Fruiting body color was white, and the shape of pileus was convex-umbonate. In the bottle culture, the yield was 115.7 g per 850 ml bottle. Stipe length was about 54 mm, the number of stipe per bottle was 18.1, the size of pileus was 28 mm, and gill was crowded. The moisture content of 'Miso' was lower than that of Jangan No.5 and Wonhyeong No.1, and contents of protein, ash and sugar of 'Miso' were higher than those of other varieties, and tannin acid content of 'Miso' was lower than that of others. On the basis of AFLP analysis, the 'Miso' was distinct not only from Wonhyeong No.1, but also from their closest relative, oyster mushrooms.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.2
• /
• pp.983-989
• /
• 2013

The current research reviewed the design conditions that would maximize the efficiency of the hybrid collector that combines in one unit "cyclone-inertial impaction-bag filter". The computational analysis for the shape of cyclone entry predicts that a design that installs the guide vane at the entry of the tangential type cyclone brings a high-rpm and powerful vortex, very effective in promoting the deflection of coarse particles from the streamline at the cyclone. As the lower part of the cyclone is venturi-shaped, however, a strong flow downward of 4 to 5 m/sec persists through the lower part of the hopper, revealing the likely reentrainment of collected dust. And the removal of the venturi at the lower part of the cyclone would solve the problem of the reentrainment of collected dust. The acceleration of the flow velocity through the adjustment of the gap of the collision baffle would increase the effect of collision, but as the interference with the dust separation is expected, the original design should be kept for the baffle.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.25 no.1
• /
• pp.23-33
• /
• 2017

In this study, water and organic treatment efficiency and operating characteristics (temperature, salinity effect) were evaluated when food waste with high water content was treated by Bio-dying method. In addition, the optimum conditions for producing pellets for evaluating the decomposition products as SRF(Solid Refuse Fuel) after Bio-drying and evaluating the use value of SRF as a solid fuel were analyzed. As a result, the temperature, $CO_2$ concentration, organic matter removal rate and weight reduction rate according to the daily dose were about 86% and 68% at the input of 2.4 kg/day. The optimal food waste input was estimated to be 2.4 kg/day. As a result of the pellet molding and produce, Pellets can be produced within 10~25% of raw material water content. It was judged that the water content of 25%, which showed the best quality results in terms of external shape maintenance and strength. The high calorific value of SRF of decomposition products after Bio-drying was more than 3,500 kcal/kg.