• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.245-257
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• 2018

The efficacy of different control techniques against the large black chafer, Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae), in organic pear (Pyrus pyrifolia) orchards was evaluated. In this study, field trials were conducted in three locations in Korea-Naju, Hampyeong, and Boseong-to evaluate different techniques to suppress these beetles. Pheromone traps, bio-insecticides (Hongmengye and Melchungdaejang), and a combination of the two were applied as treatments. In Naju, Hampyeong, and Boseong, the highest number of adult H. parallela were caught in the control plots (n=45, n=39, and n=20, respectively), while the fewest were caught in the pheromone plus bio-insecticide plot (n=19) in Naju and in the combined treatment plot in Hampyeong (n=10). In Naju, the greatest leaf damage was observed in the control (66%), and in all locations (Naju, Boseong, and Hampyeong), the least damage occurred in the combined treatment plots (42%, 36%, and 24%, respectively). Regarding the tree canopy, the greatest leaf damage was observed in the upper canopy, and less damage was observed in the lower canopy. These results demonstrate that the combination of sex pheromone traps and bio-insecticides can be used to manage H. parallela in organic pear orchards.

• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.719-724
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• 2015

Nematomorpha, horsehair or Gordian worms, include about 300 freshwater species in 22 genera (Gordiida) and 5 marine species in 1 marine genus (Nectonema). They are parasitic in arthropods during their juvenile stage. In the present study, the used gordian worm was found in the feces of a dog (5-month old, male) in July 2014. Following the worm analysis using light and scanning electron microscopes, the morphological classification was re-evaluated with molecular analysis. The worm was determined to be a male worm having a bi-lobed tail and had male gonads in cross sections. It was identified as Gordius sp. (Nematomorpha: Gordiidae) based on the characteristic morphologies of cross sections and areole on the cuticle. DNA analysis on 18S rRNA partial sequence arrangements was also carried out, and the gordiid worm was assumed to be close to the genus Gordius based on a phylogenic tree analysis.

• Parasites, Hosts and Diseases
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• v.57 no.5
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• pp.461-467
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• 2019

Avian trematodes, Urogonimus turdi (Digenea: Leucochloridiidae), were collected from the intestine of wild birds, Zoothera aurea, 2013-2017 in the Daejeon Metropolitan City, Korea. The body was ellipsoidal, attenuated and/or round ends, 1,987-2,120 long and $819-831{\mu}m$ wide. The oral sucker was subterminal, rounded anteriorly, and $308-425{\times}351-432{\mu}m$ in size; the prepharynx and esophagus were almost lacking; pharynx was well-developed, $142-179{\times}78-170{\mu}m$ in size; intestine narrow, bifurcating just after pharynx, ascending to the oral sucker before looping posteriorly and terminating near the posterior end; ventral sucker larger, in almost median, $536-673{\times}447-605{\mu}m$ and approximately 1.5 times larger than oral sucker. A phylogenetic tree constructed with 18S ribosomal RNA showed inter- and intraspecific relationships. Based on these morphological and molecular findings, we report here a U. turdi from White's thrushes in Korea.

• Journal of Veterinary Clinics
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• v.36 no.3
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• pp.133-138
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• 2019

The present study was performed to identify the nematodes recovered from the Eurasian jay, Garrulus glandarius brandtii, from Daejeon Metropolitan City, the Republic of Korea. Total five nematode worms were detected in the body cavities of two out of the twenty birds necropsied, and they were identified using morphological features, light and scanning electron microscope (SEM), and molecular (18S rRNA analysis) methods. The nematodes were all female Diplotriaena manipoli and had numerous eggs at different developmental stages in the uterus. The nematodes were long and slender measuring about 123-145 mm. The eight submedian cephalic papillae were arranged into four large, outer papillae and four small, inner-circle papillae. A pair of amphidal pores were located at the lateral portion of the mouth. The manubrium apex of trident was rounded and three branches of trident were bluntly rounded at the posterior ends. Using 18S rRNA partial sequence arrangements, DNA analysis of nematode worms was also carried out, and they were identified to be close to the Serratospiculum tendo based on a phylogenic tree analysis. To our knowledge, this is the first report on the molecular characterization and SEM study of D. manipoli.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.666-676
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• 2000

For the study of morphological variation of Q. variabilis natural population in Korea, 19 populations were selected through the country in considering latitude, longitude, and geographical characters. Thirty trees were randomly selected from each population and 60 mature leaves were sampled from each tree. Four characters (leaf blade length, maximum blade width, petiole length, and vein number) were measured, and their ratios (the ratio of blade length to maximum blade width, the ratio of blade length to petiole length, the ratio of petiole length to vein number, upper 1/3 blade width to maximum blade width, and upper 1/3 blade width to lower 1/3 blade width) were calculated. 1. Analysis of variance for all leaf characters were significantly different among populations and among individuals within population. Contributions of variance among individuals within population in all the characters were higher than those among populations. Therefore, selection of plus trees may be preferable to desirable populations for breeding program of Q. variabilis. 2. Among principal component analysis for leaf characters, primary 2 principal components appeared to be major variables for leaf form of Q. variabilis because of the loading contribution of 80.5%. The first contribution component was petiole length/vein number and petiole length ; the second one was upper 1/3 blade width/maximum blade width, upper blade width/lower 1/3 blade width and vein number, respectively. 3. Latitude was positively correlated with blade length/maximum blade width and blade length/petiole length, but negatively correlated with petiole length/vein number, upper 1/3 blade width/maximum blade width, upper 1/3 blade width/lower 1/3 blade width, petiole length, and vein number. But, for longitude and altitude the former two traits and the later five traits exhibited the negative and positive correlation, respectively. 4. Cluster analysis using complete linkage method for leaf characters showed two groups to Euclidean distance 1.6. They were group I of population 1. 4, 5, and 13 and group II of population 2, 3, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, and 19. However, group II was divided again to Euclidean distance 1.3, that is a group including population 3, 7, 10, 14, 15, and 17(group II-1) and the other group comprising population 2, 6, 8, 9, 11, 12, 16, 18, and 19(group II-2). This cluster could be mainly observed due to difference among population in aspect (group I : NE, group II-1 : SE, and group II-2 : SW).

• Journal of Korean Society of Forest Science
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• v.43 no.1
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• pp.39-50
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• 1979

Twelve Pinus taeda were used as mother trees and one P. rigida plus tree was used as pollen tree for 12 cross combinations. Nine P. densiflora plus trees(4 mother and 7 pollen trees) were used as parents for 11 cross combinations. Those parents and 10 progenies were analyzed for LAP of ${\times}$P. taeda rigida hybrid and P. densiflora and for peroxidase of ${\times}$P. taeda rigida. The analysis, based on the banding patterns, indicate three alleles for LAP-A locus(A1, A2, A3) and two alleles for LAP-B locus (B1, B2) in ${\times}$P. taeda rigida hybrids. Chi-square test on the segregation for progenies did not show significant differences. The results indicated good agreement with monohybrid Mendelian inheritance. Independence test for occurrence frequency of 2 alleles(LAP-A3, LAP-B2) illustrated that there is neither linkage nor repulsion relationship between LAP-A3 and LAP-B2 alleles. Three band at LAP-A locus were always exhibited from all parents and their progenies of P. densiflora. However, the occurrence of two bands at LAP-B locus was variable, one bands assumed as homozygous alleles(B2/B2) and two bands as heterozygous alleles(B1/B2). The segregation ratio for progenies of P. densiflora suggested that LAP-B locus may be controlled by two alleles(B1 and B2). Three Peroxidase loci(Px-A, Px-B, Px-C) assumed to be controlled by allozyme in ${\times}$P. taeda rigida hybrid. The Px-B and Px-C loci could not find out the variations from banding patterns of parents and their progenies, while the Px-A locus showed the variations of occurrence frequency by two bands. The segregation ratio for A1/A2 at LAP-A locus suggest that the peroxidase allozymes of ${\times}$P. taeda rigida hybrid appeare to be monomeric products; that is, Px-A locus may be controlled by two alleles (A1 and A2).

• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.1-8
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• 1976

One of the most common needle leaf species used in planting in Korea is korean pine (Pinus koraiensis S. et Z.), and jack pine (Pinus banksiana Lamb.) is one of the test species for suitability. The relation of nursery bed density of 2-1 korean pine and 1-1 jack pine was studied at the Kwang Nung Nursery, Central Branch Station of Forest Research Institute, and about 40km north of Seoul. Nursery bed density of 2-1 korean pine, which ranged from 36 to 324 trees per square meters and of 1-1 jack pine, which ranged from 25 to 169 trees per square meters, had a marked effect on caliper, height, dry weight and percent and amount of plantable stock. The soil physical and chemical properties is silt plus clay, 50.55 percent; organic matter, 2.09 percent; total nitrogen, 0.13 percent; available phosphorus, 253.25 ppm; exchangeable potash, 0.46 m.e/100g; and pH, 5.58. As the density of the nursery seedling stand of 2-1 korean pine increases, the average tree height increases (Fig. 1A), but in 1-1 jack pine density do not affect to increase or decrease the average tree height. As the density of nursery bed increases, the average stem caliper (at 2cm above ground line) and dry weight decrease (Fig. 1B), but the decreasing rate is more seriously in 1-1 jack pine than 2-1 korean pine (Fig.5). As increasing the density of nursery bed, the T/R ratio of trees of the test species increase. Also the dry weight of leaf, stem and root parts are decreasing in proportion to the increase of stand density, but the drop rate of jack pine is more rapid than korean pine (table. 1) The patent facts of difference of growth characteristics between 2-1 korean pine and 1-1 jack pine were studied. These facts should be used to select the scale of stand density at the nursery bed or the plantable site. Korean pine is demanded high density, on the other hand in jack pine low density are more suitable to manage the stand density. Stands of comparatively low density had the greatest percentage of high-quality stock, and the stands of high density had less than the high quality trees of low density. An important criterion of the best density is percent and number of high-quality trees produced per square meter of bed area. Stem caliper and stem height of seedling is used in most public nurseries to sort seedling into plantable grades. The stock grade standard has set at 4.5mm caliper and 16cm height of 2-1 korean pine as the minimum desired stem caliper and height. By the result studies, the plantable stock grade standards of 2-1 korean pine used at stem height 16cm and stem caliper 4.5mm from public nurseries should be reformed to stem height 18cm and stem caliper 4.0mm by the growth characteristics and the tree distribution of stem height and caliper of relation to density. For the 2-1 korean pine, best density should be about 160 to 200 trees per square meter according to soil fertility. For the 1-1 jack pine, the suitable standard of plantable stock should be at stem height 25cm and caliper 6mm (at 2cm above ground line) and best density was about 100 to 120 trees.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.243-243
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• 1994

Although active systemic anaphylaxis and passive cutaneous anaphylaxis have been empolyed to study anaphylactic hypersensitivity, it is difficult and time-consuming to induce these reactions in experimental animals. In recent, Jun et al have found a simple method to induced anaphylactic hypersensitivity such as anaphylactic shock(AS) and cutaneous reaction(CR) using compound48/80. Cortex mori (Morus alba L.), the root bark of mulberry tree has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine. The purpose of this study was to determine whether the methanol extract of Cortex mori could inhibit the compound 48/80-induced AS and CR. To induce AS, various doses of compound 48/80 (5, 7.5, 10, 15$\mu\textrm{g}$/gm B.W.) were injected intraperitoneally (i.p.) into ICR mice. The animals were pretreated by three injection(i.p.) of Cortex mori before compound 48/80 administration. Peripheral blood was collected from the right ventricle to estimate the level of serum histamine at 15 minutes after the injctin(i.p.) of various concentration of compound48/80. Mortility rate, mean death time and mesenteric mast cell degranulation rate were evaluated over a 72 hour period. To estimate the effect of Cortex mori on compound 48/80-induced cutaneous reaction, various doses of compound 48/80 with or without Cortex mori were injected intradermally(i.d.) into the shaved flank of Sprague-Dawley rats, and the blue cutaneous patchs induced by Evans'blue injection at the compound 48/80 alone and Cortex mori plus compound 48/80 injection sites were observed. As a Parameter of these reactions, the levels of histamine in the supernatant, calcium uptake and intracellular CAMP of RPMC were measured. supernatant, 1)compound 48/80-induced mortility rate, mean death time, mesenteric mast cell degranulation rate, and serum histamine level in ICR mice were significantly inhibited by pretreatment of Cortex mori, 2) cutaneous reaction inducd by compound48/80 was well developed in Sprague-Dawley rat, but Cortex mori inhibited the compound 48/80-induced blue patch formation remarkably, 3) the compound 48/80-induced degranulation, histamine release and calcium uptake of RPMC pretreated with Cortex mori were significantly inhibited, compared to those of control without Cortex mori pretreatment, and 4)the level of cAMP of RPMC was reduced bythe increased concentration of compound 48/80, pretreatment of Cortex mori not only inhibited the compound 48/80-induced reduction of CAMP but also significantly increased the level of cAMP naturally, from the above results, it is suggested that Cortex mori has an some substances with an ability to inhibits the compound 48/80-induced AS,CR, and mast cell activation.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.45-52
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• 1999

This study was conducted to evaluate the effects of microbial inoculation on sewage sludge composting. The number and species of microorganisms in sewage sludge sampled on February were higher than those sampled on August. The composting of sewage sludge is inhibited by the polyacrylamide cation, which was used as a coagulant and known to repress the growth of microorganisms. The growth of all microorganisms was inhibited by the addition of the polyacrylamide cation at a concentration of more than 0.8%. The species and viable counts of microorganisms were observed to increase during composting sewage sludge by inoculation of the effective microorganisms and addition of the pine tree sawdust as a bulking agent, compared with those without inoculation. A variety of organisms in compost(sewage sludge plus sawdust) were observed after composting for 30 days, such as Fragilaria sp., Proales sp., Vorticella sp., Schizothrix sp., Anabaena sp., Zoothaminium sp., Epstylis sp., Arcella sp., Balantidium sp., Actinophrys sp., Synedra sp., Euglypha sp., Ulothrix sp., Anacystis sp., and Clostium sp.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.235-243
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• 2002

Ni-base superalloys are used extensively in industry, both in aeroengines and land based turbines. About 60% by weight of most modern gas turbine engine structural components are made of Ni-base superalloys. To satisfy practical demands, the efficiency of gas turbine engines has been steadily and systematically increased by design modifications to handle higher turbine inlet or firing temperatures. However, the increase in operating temperatures has lead to a decrease in the life of components and increase in costs of replacement. Moreover, around 80% of the large frame size industrial/utility gas turbines operating in the world today were installed in the mid-sixties to early seventies and are now 25 to 30 years old. Consequently, there are greater opportunities now to repair and refurbish the older models. Basically, there are two major factors influencing the weldability of the cast alloys: strain-age cracking and liquation cracking. Susceptibility to strain-age cracking is due to the total Ti plus AI content of the alloy; Liquation cracking is due either to the presence of low melting constituents or constitutional liquation of constituents. Though Rene 41 superalloy has 4.5wt.% total Ti and Al content and falls just below the safe limit proposed by Prager et al., controlled grain size and special heat treatments are needed to obtain crack-free welds. Varying heat treatments and filler materials were used in a laboratory study, then the actual welding of service parts was carried out to verity the possibility of crack-tree weld of components fabricated from Rene 41 superalloy. The microstructural observations indicated that there were two kinds of carbides in the FCC matrix. MC carbides were located along the grain boundaries, while M$_{23}$C$_{6}$ carbide was located both inter and intra granularly. Two kinds of filler materials, Rene 41 and Hastelloy X were used to gas tungsten arc weld a patch into the sheet metal, along with varying pre-weld heat treatments. The microstructure, hardness and tensile tests were determined. The service distressed parts were categorized into three classes: with large cracks, with medium cracks and with small or no visible cracks. No significant difference in microstructure among the specimens was observed. Specimens were cut from the corner and the straight edge of the patch repair, away from the corner. The only cracks present were found to be associated with inadequate surface preparation to remove oxidation. Guidelines for oxide removal and the welding procedures developed in the research enabled crack-free welds to be produced.d.