• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.159-166
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• 2008

This research was carried out to test and analyze capacity of the long distance sprayer fan in large livestock farmhouses. Long distance sprayer was manufactured to be able to spray a lot of water, which was a solvent for agricultural chemicals and black dye with the maximum spraying distance of 140 m and the effective spraying distance of 100 m. The spraying quantity and the distance were measured the intensity values of images within A4 papers, which absorbed the agricultural chemicals by spraying by binary image processing. These A4 papers were fixed upon the height of 1 m from soil ground at regular 10 m interval. After the A4 papers were collected and analyzed the intensity values of gray level. Gray level was ranged from 0 to 255, where 0 was black and 255 was white. A4 paper was fallen down from the stick at 10 m distance, because there were too large amount of sprayed water with black dye. Also, the paper showed low gray level at distance 30 m because of dropping lots of black water. The intensity value of gray level was showed almost less than 200 on the A4 papers between the distance 20 m and 100 m, which meant equality of spraying quantity. Additionally, it was possible to spay agricultural chemicals of until 180 m. Throughout this research, long distance sprayer could apply for preventing hoof-and-mouth disease in large livestock farmhouses.

• The Plant Pathology Journal
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• v.33 no.5
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• pp.499-507
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• 2017

In an attempt to develop a biological control agent against mycotoxigenic Fusarium species, we isolated Bacillus amyloliquefaciens strain DA12 from soil and explored its antimicrobial activities. DA12 was active against the growth of mycotoxigenic F. asiaticum, F. graminearum, F. proliferatum, and F. verticillioides both in vitro and in planta (maize). Further screening using dual culture extended the activity range of strain DA12 against other fungal pathogens including Botrytis cinerea, Colletotrichum coccodes, Endothia parasitica, Fusarium oxysporum, Raffaelea quercus-mongolicae, and Rhizoctonia solani. The butanol extract of the culture filtrate of B. amyloliquefaciens DA12 highly inhibited the germination of F. graminearum macroconidia with inhibition rate 83% at a concentration of $31.3{\mu}g/ml$ and 100% at a concentration of $250{\mu}g/ml$. The antifungal metabolite from the butanol extract was identified as iturin A by thin layer chromatography-bioautography. In addition, volatile organic compounds produced by DA12 were able to inhibit mycelial growth of various phytopathogenic fungi. The volatile compounds were identified as 2-heptanone, 5-methyl heptanone and 6-methyl heptanone by gas chromatography-mass spectrometry (GC-MS) analysis. These results indicate that the antagonistic activity of Bacillus amyloliquefaciens DA12 was attributable to iturin A and volatile heptanones, and the strain could be used as a biocontrol agent to reduce the development of Fusarium diseases and mycotoxin contamination of crops.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.329-336
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• 1987

Antagonistic interaction between glyphosate and some herbicides in effects of post-emergence application on cut grass and of pre-emergence application on some weed species including barnyardgrass was evaluated with pots in plastic house. By addition of oxyfluorfen to glyphosate, the weeding efficacy on cutgrass was visually evaluated as promotive in both weeding rate and efficacy. However, by alachlor, simazine, gluphosinate or quizalofop-ethyl showed delayed weeding rate, and by paraquat, the promotive in rate but lower in efficacy, respectively. Fresh weights of cutgrass at 30 days after the lower-rate application has generally indicated the lower weeding efficacy than that from glyphosate alone. Even at higher rate application, the addition of alachlor or simazine to glyphosate has still indicated the lower efficacies. As a result of interaction analysis by Colby method, no synergism was detected from any treatments, and the combinations of simazine or paraquat to glyphosate in lower mixing rate showed significant antagonism at 5% probability level of DMRT. On the annual weed species including barnyardgrass, the significant soil-residual weeding efficacies were recognized by addition of any rate of oxyfluorfen, alachlor, simazine and higher rate of quizalofop-ethyl to glyphosate, respectively.

• Journal of Cadastre & Land InformatiX
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• v.46 no.2
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• pp.27-42
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• 2016

Forest accounts for almost 64 percents of total land cover in South Korea. For inventorying, monitoring, and managing such large area of forest, application of remote sensing and geographic information system (RS/GIS) technology is essential. On the basis of spectral characteristics of satellite imagery, forest cover and tree species can be classified, and forest cover map can be prepared. Using three dimensional data of LiDAR(Light Detection and Ranging), tree location and tree height can be measured, and biomass and carbon stocks can be also estimated. In addition, many indices can be extracted using reflection characteristics of land cover. For example, the level of vegetation vitality and forest degradation can be analyzed with VI (vegetation Index) and TGSI (Top Grain Soil Index), respectively. Also, pine wilt disease and o ak w ilt d isease c an b e e arly detected and controled through understanding of change in vegetation indices. RS and GIS take an important role in assessing carbon storage in climate change related projects such as A/R CDM, REDD+ as well. In the field of climate change adaptation, impact and vulnerability can be spatio-temporally assessed for national and local level with the help of spatio-temporal data of GIS. Forest growth, tree mortality, land slide, forest fire can be spatio-temporally estimated using the models in which spatio-temporal data of GIS are added as influence variables.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.44-49
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• 2002

The study was conducted to isolate and identify insecticidal bacteria for biological control of larvae of mushroom fly, Lycoriella mali, which is one of serious pests to oyster mushrooms during its cultivation period. Among eight bacteria isolated from the soil in the oyster mushroom beds and the dead body of L. mali, two bacteria, Bti-D and Bti-U showed more toxicity with mortality rate than other six-bacteria isolates. The two bacteria showed more toxicity in three instar of the period of development of the mushroom fly than in other instar. Symptoms of the larvae of L. mali infected by the two bacteria developed as follows: at the early infection, the front middle gut changed color to light brown, the middle gut to brown, whole body to black brown, and eventually, the fly died. For the identification of these isolates, cultural and biochemical characteristics by Bergey's manual and Biolog system, cell morphology by TEM, endospore and endotoxin by phase-contrast microscope, and test using 33H antisera were examined. According to the results, these two isolates, Bti-D and Bti-U were identified as Bacillus thuringiensis subsp. israelensis respectively.

• Microbiology and Biotechnology Letters
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• v.7 no.3
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• pp.135-140
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• 1979

A Streptomyces sp. strain AS-727 which was capable of producing penicillinase, was isolated from soil. The enzyme production was affected by the carbon and nitrogen sources added. Among them so far tested, glucose (or maltose) and sodium nitrate increased the enzyme production. And the amount of enzyme prodced reached maximum in 4 days cultivation. The optimla pH and temperature of the penicillinase was between pH 6.0 to 8.0 and 4$0^{\circ}C$ respectively. The stabel pH range of the enzyme was stable at 4$0^{\circ}C$, but it lost about 30％ and 40％ of the the activity respectively when it was treated at 6$0^{\circ}C$ and 8$0^{\circ}C$ for 60 minutes. The activity of the enzyme was inhibited by Z $n^{++}$, but A $g^{+}$, $Co^{++}$, $_Mn^{++}$, $Ca^{++}$, P $b^{++}$ did not affected enzyme activity. Peculiarly, the enzyme protein precipitated by freezing or addition of ammonium sulfate, urea, sodium chloride and some organic solvents as etanol, methanol, acetone was not dissolved in deionized water or any buffer solution.n.n.ion.n.n.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.3
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• pp.172-178
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• 2003

This study was conducted to assess the physiological tolerance of native tree species for successful restoration and revegetation of abandoned coal-mine spoils. Study sites were two coal-mine spoils (Sododong and Ssarijae) in Taebaek, Kangwon Province, Korea. Five individuals of Betula costata and of B. schmidtii were analyzed for malondialdehyde (MDA) and hydrogen peroxide ($H_2O$$_2$) content, nitrate reductase (NR) and superoxide dismutase (SOD) activity, and for carbohydrate concentration in the leaves. Trees in the abandoned coal-mine spoils were influenced by deficiencies expressed by MDA and $H_2O$$_2$ content in the leaves of two species being higher at the coal-mine spoils than in the surrounding forest. Low NR activity indirectly represented nitrogen deficiency in the soil of the coal-mine spoils; an unmanageable SOD activity implied that tolerant functions didn't net against a certain stress of the coal-mine spoils. Decreased glucose and increased starch concentration especially showed the inhibition of the carbohydrate metabolism by inadequate factors. Consequently, low nitrogen content in the real-mine soils might increase damage in trees as a result of inhibiting the expression of tolerance mechanisms against stress. Therefore, trees in coal-mine spoils need ample nitrogen to use as a metabolic energy source in order to prevent damage and increase tolerance against stress.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1286-1298
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• 2005

The genus Paenibacillus is a new group of bacilli separated from the genus Bacillus, and most of species have been isolated from soil. In the present study, we collected 450 spore-forming bacilli from the roots of winter crops, such as barley, wheat, onion, green onion, and Chinese cabbage, which were cultivated in the southern part of Korea. Among these 450 isolates, 104 Paenibacillus-like isolates were selected, based on their colony shape, odor, color, and endospore morphology, and 41 isolates were then finally identified as Paenibacillus spp. by 16S rDNA sequencing. Among the 41 Paenibacillus isolates, 23 were classified as P. polymyxa, a type species of the genus Paenibacillus, based on comparison of the 16S rDNA sequences with those of 32 type strains of the genus Paenibacillus from the GenBank database. Thirty-five isolates among the 41 Paenibacillus isolates exhibited antagonistic activity towards plant fungal and bacterial pathogens, whereas 24 isolates had a significant growth-enhancing effect on cucumber seedlings, when applied to the seeds. An assessment of the root-colonization capacity under gnotobiotic conditions revealed that all 41 isolates were able to colonize cucumber roots without any significant difference. Twenty-one of the Paenibacillus isolates were shown to contain the nifH gene, which is an indicator of $N_{2}$ fixation. However, the other 20 isolates, including the reference strain E681, did not incorporate the nifH gene. To investigate the diversity of the isolates, a BOX-PCR was performed, and the resulting electrophoresis patterns allowed the 41 Paenibacillus isolates to be divided into three groups (Groups A, B, and C). One group included Paenibacillus strains isolated mainly from barley or wheat, whereas the other two groups contained strains isolated from diverse plant samples. Accordingly, the present results showed that the Paenibacillus isolates collected from the rhizosphere of winter crops were diverse in their biological and genetic characteristics, and they are good candidates for further application studies.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.6
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• pp.87-100
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• 2016

This research was performed for the purpose of providing useful and base data and preservation strategy of growth characteristics of Rhododendron micranthum. From the result of research, wild growth area of Rhododendron micranthum was discovered near steep forest road on 695~901m in altitude above sea level of Baekdu-daegan National Arboretum. Vegetation colony structure of Site I was resulted in Pinus densiflora(tree stratum M.I.P.=45.3%) is dominants, Betula schmidtii(arborescent M.I.P.=9.8%) is second dominant, and Site III resulted in Pinus densiflora(tree stratum M.I.P.=30.5%) is dominants, Betula schmidtii(arborescent M.I.P.=10.3%) is second dominant. Site II resulted in Betula schmidtii(arborescent M.I.P.=30.4%) is dominants and Pinus densiflora tree(tree stratum M.I.P.=8.3%) is second dominants. For herbs, it was researched that the rate of one year herb of chrysanthemum family(10), rice family(3), sedge(2) was higher than near forest area. Among Species diversity index, that of Shannon was in range of 0.7348~1.1090. After comparing this with similar area, this value was relatively low. Dominance analysis result was analyzed that various groups are evenly distributed. Monthly highest average temperature is $23.9^{\circ}$ in Site A and Site B, and monthly lowest average temperature is $-4.5^{\circ}C$ in Site I and $-4.7^{\circ}C$ in Site II. Monthly maximum average humidity is 85.6% in Site I and 83.2% in Site II. Monthly minimum average humidity is 60.9% in Site I and 60.8% in Site II and it showed that these 2 area are located far away but have similar temperature and humidity characteristic and climate environment is similar. It was analyzed that humidity is high with the result of annual average humidity is over 60%. In growth characteristic, it showed that doubt damage of Stephanitis pyrioides, exposure of roots, peeled bark was discovered and supplement on this is urgent.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.675-687
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• 2005

In this study, the cyclone/denuder/filter pack sampling system was used to measure the daily concentrations of water soluble inorganic compounds of fine ($D_{p}< 2.5\;{\mu}m$) and coarse ($D_{p}<10{\mu}m$m) size fractions of aerosol and related gases at Gosan super site during ABC-EAREX 2005. The mean concentrations for $HNO_{3},\;HNO_{2},\;NH_{3}$, were 0.39, 0.08, and $0.29\;{\mu}g/m^3$. respectively. Average concentrations of sulfate, nitrate, and ammonium in $PM_{2.5}$ were 3.39, 1.06, and $1.04\;{\mu}g/m^3$, which occupied about $26\%$ of total $PM_{2.5}$ mass. In particular, more than half of these ionic species were found in size of less than $2.5\;{\mu}m$. Gas phase nitric acid concentrations have shown high correlation coefficient with $HNO_{2}$(R=0.80) and $O_{3}$(R=0.78), implying the active photochemical reactions from its precursors. Equivalent molar ratios between major ion components, $NH_{4}\;^{+}/nss\;SO_4\;^{2-},(0.83\;for\;PM_{2.5},\;0.86\;for\;PM_{10})$, revealed that the existing forms of the secondary aerosols were probably $(NH_{4})_{2}SO_{4}\;and\;(NH_{4})_{3}H\;(SO_{4})_{2}$. Especially, $(NH_{4}\;^{+}+K^{+}+Ca^{2+}+Mg^{2+})/(NO_{3}\;^{-}+nss\;SO_{4}\;^{2-}) (0.99\;for\;PM_{2.5},\;1.05\;for\;PM_{10})$ indicated that some of them existed not only as $NH_{4}NO_{3}$ but also as $CaSO_{4}\;or\;KNO_{3}$, which pointed out the probability of influences from the abundant soil components during Asian dust (AD) periods. These neutralized types of secondary aerosols showed that pollutants could be aged and transported from a distance.