• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.358-364
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• 2011

To examine the possibility of natural regeneration of six Acer species in broadleaved mixed forest in Korean peninsula, samples of six Acer species' samaras were collected at several seed sources from September to October 2009 and 2010, and seed morphological characteristics and viability were studied using cutting method. Inflorescense type of Acer mandshuricum(AM), A. pseudosieboldianum(APS) and A. palmatum(AP) is corymb, that of A. pictum subsp. mono(APSM) and A. okamotoanum(AO) is flat-topped panicle, and that of A. ukurunduense(AU) is raceme. Number of seed-set per inflorescense proves the highest value 38.5 sets in AU and the lowest value 2.4 sets in APS. Diameter of the seeds proves highest value 13.5mm in AO, and the lowest value 4.7mm in APS. Angles between the wings proves the highest values $130.05^{\circ}$ in APS, and the lowest value $48.60^{\circ}$ in AU. Air dry weight of 20 seed-sets proves highest value 3,900mg, in AO, and the lowest value 404mg in AU. Viable seed ratio of AP proves 50%, and that of AU does 43.2%. Those of other four species ranges 8.6~22.2%. Considering postdispersal seed predators and disturbance of litter, viable seeds of APSM, AO, AM, and APS supplied in the natural forest in Korea might be insufficient for seedling establishment. This study showed that sound viable seed supply might be key factors of natural regeneration of major Acer species in Korea. The openings made by insect pests were observed on the seed-coat of APSM, AM, AU, and APS samara, and Bradybatus sharpi were observed in the samaras of APSM and AO. Further study on the seed insect fauna, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.109-118
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• 1987

The purpose of this study was to investigate the inhabiting ecology of wild birds using artificial nests in Gyeongnam province. The sort of birds, the utilization of artificial nests by the materials, by the sites and by the forest type, and other inhabiting ecology of birds were investigated from 1984 to 1986. The results obtained were as follows; 1. Wild birds in surveyed areas were classified into 20 families and 35 species. Among them the birds inhabiting the artificial nests were 6 species and those using them most frequently were Parus ater (17.2%), P. major (16.7%) and P. palustris (12.2%). 2. The artificial nests installed on the top and at the toot of the mountain were chiefly utilized by P. ater and P. major, but the artificial nests in park area were mostly used by Passer montanus and Sturnus cineraceus. 3. Sixty-one percent of the artificial nests were utilized by the birds; 45.5% were used for breeding and 15.6% were inhabitation only. 4. When different nest materials and shapes were tested, mixed nests (sawdust and cement) were used most frequently, and C type. (Diamond shape) of wood nests was used more frequently compared with the A (Roof shape) and B (Box shape) types of wood nests. Meanwhile, the birds prefered the 3cm hole size (81.1% of utilization) to 4cm of hole (57.8%) and 5cm of hole (24.4%). 5. The artificial nests constructed in mixed forest were more frequently inhabited (73.3%) by the birds than coniferous forest (68.3%) and broad-leaved forest (63.3%). 6. The period of egg-laying in Parus species was from late April to early May, while Eophona migratoria, Lanius bucephalus, Motacilla alba and Passer montanus laid eggs generally in the middle of May. 7. Parus species, Passer montanus and Motacilla alba laid one egg every day for 5-10days, but Eopphona migratoria laied 4 eggs in 7 days and Lanius bucephalus laid 5 eggs in 4 days. The incubation period of Parus species was 16-18 days, while the others were about 11 to 14 days. 8. Thirteen days after the hatch of Parus major, chicks reached 13.9g of body weight, 72.0mm of wing-length and 20.9mm of tarsus length. P. montanus chicks reached 20.3g of weight, 66.2mm of wing-length and 20.2mm of tarsus length during the same period. 9. Food item of feeding chicks almost consisted of creatures (98.2%) with following composition; 55.2% of insect larvae, 37.2% adult insects, 2.8% of pupae and 2.8% of spiders. Vegetable items were 2% only. Among those creature food items, 95.2% were insect pests to forest.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.257-268
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• 1990

The regional characteristics in the occurrence of the rice stem borer, Chilo suppressalis (Walker), in Korea, were examined by analyzing the light trap data obtained from 39 locations during the years of 1965-1988, and some ecological significance of the overwintering larval populations collected from the four locations where some of the typical ecological-race have been known, the results obtained are as follows; The total number of the moths have decreased greatly throughout the nation since 1970. The decrease in the total number of moths related with those in the spring moth but not in the summer moths, and suggested that the changes in the rice production systems have effected significantly on the second generation of the insect. The variations between the regions had been gret in 1960's, decreasing phase in 1970's and increasing phase in loast decade. The overall average of 50% emergence dates have shifted earlier in both moths, and the changes were different considerably with the regions as wheel as in generations. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were 21.07% for Suweon, 43.06% for Iri, 63.51% for Jinju, 27.04% for Gwangju. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were different with the body weight; 45.44% for the larvae of less than 39 mg, 37.61% for 40-49 mg, 37.28% for 50-59 mg, 30.17% for greater than 60 mg. When the overwintered larvae wee incubated at $25^{\circ}C$, post-diapause larval development periods of body weight classes were 18.6$\pm$1.2 days for the larvae of less than 39 mg, 20.4$\pm$3.3 days for 40-49 mg, 21.4$\pm$3.2 days for 50-59 mg, 21.8$\pm$3.2 days for grater than 60 mg, and only the larvae of less than 39 mg, body weight class less than 39 mg was found statistically different in post-diapause larval development periods. From these results, the changes in the cultural practice of the rice have effected on the ecological pattern of the rice stem borer, and the effects seemed to be different with the generations, and with the regions where the different ecological races are distributing.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.621-631
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• 2021

The purpose of this study is to survey and analyze acorn production and characteristics of the Quercus acuta Thunb. according to the need for information on seed supply and seedling cultivation during the restoration of warm broad-leaved forests. For the survey, a total of 30 seed traps with a surface area of 1 m² were set up, 3 in each of 10 quadrats (8 in Wando, 1 in Haenam, and 1 in Jindo). The acorns that fell in the seed trap at the end of each month were collected from August to December each year between 2013 to 2016. The collected acorns were then classified into sound, damaged, decayed, or empty grade, and the number of acorns produced was calculated. In the case of sound acorns, acorn traits, such as length, diameter and weight of acorns without cupule, were measured. Duncan's multiple tests of acorn production and characteristics were conducted for comparative analysis of the annual average values with the values by year, stand, month, and treatment plot. The annual number of acorn dropped into the seed traps in each quadrat from 2013 to 2016 was 5-350 acorns/3 m² in 2013, 17-551 acorns/3 m² in 2014, 5-454 acorns/3 m² in 2015, and 14-705 acorns/3 m² in 2016. There was a large difference in acorn production between the quadrats, presumably attributed to the difference in the amount of light received due to the density of trees in the square. Annual acorn production per area was 335,000 acorns/ha in 2013, 932,000 acorns/ha in 2014, 556,000 acorns/ha in 2015, and 1,037,000 acorns/ha in 2016. That was a sharp variation of acorn production in the two-year cycle. As the fluctuation in the production of Q. acuta showed simultaneity between stands, it is judged that Quercus acuta Thunb. had a clear cycle of fruitfulness and fruitiness between forest objects. September showed the biggest amount of fallen acorns and largest damage from insect pests, indicating that preventing early fall of acorns could increase the fruiting period and enable mass production of sound acorns. There was no significant difference between annual average acorn length in each region. In the case of the acorn diameter and weight, the average values of acorns from Haenam were significantly higher than those from Wando and Jindo. There was no significant difference in the average annual acorn characteristics by month, and the average annual acorn length, diameter, and weight in November were 19.72mm, 12.23mm, and 1.64g, respectively, the highest between August and November.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.124-133
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• 2009

Demand for the high quality barley with fibroid material and functional substances has been increasing in recent although the amount of barley consumption decreased drastically during the last two decades. But the limited information on quality of barley makes consumers hard when they purchase barley for their own consumption. Therefore, 51 brand barley, .i.e., 28 naked barley and 23 waxy barley from supermarkets and 10 polished barley from local markets were collected, and their external quality were analyzed to provide basic information on brand barley. Among 51 brand barley, 56% were 1kg package and 25% were 800 g package and there was no significant difference ($1{\pm}3.62\;g$) between printed and actual weighs. The weight of 1,000 grains of naked barley and waxy barley ranged $18.6{\sim}26.7\;g$ and $14.6{\sim}24.7\;g$, respectively. Thousand grain weight of 38% of naked barley ranged $20{\sim}22\;g$, while that of 43% of waxy barley ranged $18{\sim}20\;g$. The ratio of normal grains was 88% and 94% for naked barley and waxy barley, respectively, when separated with 1.7 mm sieve. Although 82% of brand barley products were free from foreign substances, in 18% of brand barley products, sands, pieces of cloth and wood, other kinds of grain and insect larvae were found, Average test weight of brand barleys was $843g{\cdot}L^{-1}$ with range of $805{\sim}917g{\cdot}L^{-1}$. Water content was less than 14% in 7.8% of barley products, while it was $14{\sim}15%$ in 62.7% of them. Average whiteness of brand barley was 31.06, while waxy barley had higher whiteness with 27.28 than naked barley with 34.16. Heated water uptake rate of milled naked barley and milled waxy barley were 215.4% and 231.7%, respectively, while expansion rate of milled naked barley and milled waxy barley were 379.7% and 401.6%, respectively. Barley from local markets were as good as brand barley products in 1,000 grain weight, ratio of normal grains, inclusion of foreign substances, test weight, water content, whiteness, water uptake rate, and expansion rate, but they showed higher ratio of foreign substances included.

• Korean Journal of Veterinary Service
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• v.38 no.3
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• pp.173-180
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• 2015

Environmental pesticides used for insect control can be transferred from plants to animals even to livestock animals through food chain. Human beings also can be exposed to pesticides by consuming polluted dairy products, including meats, eggs and other milk products. Therefore, the Ministry of Food and Drug Safety (MFDS) established Standard for Pesticide Residue Limits in dairy products. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methods for detecting residual pesticides are relatively well established for fruits and vegetables, however, the methods for meat have not been appropriately studied yet. In the present work, pyraclofos was used as an organophosphate pesticide to examine its tissue residue in experimental animals by QuEChERS methods. For this, pyraclofos (150 mg/kg body weight) was orally administered to male rats once a day for 2 days. After 6, 12, and 24 hr of the treatment, the tissue residues in liver and femoral muscle of the rats were determined using QuEChERS methods followed by HPLC analyses. In preliminary studies, the recovery rates of spiking samples of pyraclofos demonstrated approximately 109~110% from the tissues. In previous study, pyraclofos tissue residues were observed with significantly high levels in livers and muscles at 6 hr of oral treatment. Then, they were almost completely disappeared after 24 hr of the administration, indicating the orally exposed pyraclofos is rapidly absorbed and distributed to body organs, then quickly excreted from the body with a negligible level of tissue residue. The alterations in blood chemistry as well as the histopathology of heart, lung, liver, spleen and kidney have also been investigated in the experimental animals for assessing acute toxic effects of pyraclofos. The obtained blood chemistry indexes (ALT and AST) showed maximum peak values at 12 hr after the oral administration and decreased to the normal levels at 24 hr of the treatment. Histopathologic observation exhibited acute hepatic damages at 24 hr of the treatment. In conclusion, we suggest that QuEChERS method can be adequately optimized for the analysis of pyraclofos residues in animal tissues.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.123-127
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• 2003

In order to develop the crude forage maize hybrids with high dry matter and grain yield, several hybrids evaluated as superior hybrids at three regions in 2001. They were planted and surveyed again for second selection in 2002. The selected hybrids showed large difference in some major characteristics according to planting areas and dates(Suwon ; April 25, Daejeon ; May 15 and Milyang ; May 25), but insect and disease injury were similar to check. Fresh and dry weight of the H67 hybrid at Suwon and Daejeon was the highest among hybrids including check, but low in Milyang due to raining after flowering. Grain yield was higher than check in H15 at Suwon, H45 and H37 at Daejeon and H67 at Milyang.

• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.49-55
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• 1980

Monoterpenes, phenolic substances, growth substances and total nitrogen from normal needles and infested needles attacked by Thecodiplosis japonensis were compared for Pinus densiflora, Pinus thunbergii and Pinus rigida. The results obtained in this study were as follows: 1. Major monoterpene components in P. densiflora needles were ${\beta}$-phellandrene, ${\alpha}$-pinene and those in P. rigida needles were ${\beta}$-pinene and ${\alpha}$-pinene. In P. rigida resistant to this insect, infested needles showed higher ${\alpha}$-pinene, ${\beta}$-pinene and myrcene but lower camphene, limonene and ${\beta}$-phellandrene than normal needles. 2. Orcinol, catechol ferulic acid, salicylic acid and five unknowns were detected in P. rigida needles whereas orcinol, catechol, ferulic acid and four unknowns in P. densiflora needles. 3. Tryptophan, a precursor of IAA, was detected in larvae and also in gall tissues of both P. densiflora and P. thunbergii needles. This fact shows that growth substances may involve in gall formation by Thecodiplosis japonensis. 4. Total nitrogen contents per unit needle weight were neither significantly different between P. densiflora and P. rigida, nor between normal and infested needles.

• Applied Biological Chemistry
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• v.19 no.1
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• pp.1-23
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• 1976

The female moths of Lepidoptera comprising over 1,000,000 described species possess long-chain unsaturated alcohols or esters as the typical structure of potential sex attractants. In this experiment, various stereoisomers of $C_{16}-unsaturated$ acetates were synthesized for potential sex attractants; e.g., $CH_3(CH_2)_mCH=CH(CH_2)_nOR$ (m=0-12, n=1-13, R=H and $-COCH_3$). Seventeen acetates were spectrometrically examined so that the data would provide a ready catalog of gas chromatography and mass spectrometric data for comparison with natural insect sex attractants. Exclusively cis and trans isomers were obtained by the catalytic and chemical reduction methods, respectively. Commercially available $CH_3(CH_2)_mBr,\;CH_3(CH_2)_mC{\equiv}CH,\;HC{\equiv}C(CH_2)_nOH\;and\;HO(CH_2)_n\;OH$ were used for the synthetic starting material. 1-Alkynes, $CH_3(CH_2)_m\;C{\equiv}CH$ exceeding nine methylene groups did not condense with alkyl dihalides. The yield of coupling products was gradually decreased with increasing the molecular weight of diols. In the coupling reaction of $BrCH_2CH_2$ OTHP with acetylene gas, the tetrahydropyranyl ether of bromohydrin produced undesirable elimination product. In this experiment, it seems that p-toluenesulfonic acid is greatly favoured hydrolyzing agent over dilute sulfuric acid in the hydrolysis of the tetrahydropyranyl ether of long-chain alkynols.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.192-197
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• 1979

Spread factors were tried to determine the diameter of airborne droplet emitted: from the sprayer by the measurements of airborne droplet diameter emitted from the uniform size droplet producer and impression diameter on Kromekote card or Eucalypt's leaf in the different dilute concentration with Geigy Red Herbicide Dye from 0.5% to 2% by weight. The results abtained were as follows; The general form of the equation in the relationship between airborne droplet and impression diameter on Kromekote card or Eucalypt's leaf was an exponential equation as follows; $$Y=aX^b$$ which gave a linear relation on log-log graph paper. The spread factor seemed to be larger in the thin dilute concentration than in the thick dilute concentration. The spread factor was remarkably smaller on Eucalypt's leaf than on Kromekote card due to the penetration of liquid into the leaf and the stomata of the epidermis. The calculated equation of the mean depth of the droplet sprayed on Eucalypt's leaf was the same form as $Y=aX^b$, which implied that the spray liquid was distributed in surplus in accordance with the diameter of the droplet larger than the optimum size droplet to control insect and disease.