• 한국노년학
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• v.37 no.3
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• pp.727-745
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• 2017

This study purported to examine the effects of precarious employment and social capital on the changes of self-rated health status among the middle aged and the young-old population in South Korea. The study analyzed 12 year follow-up data generated by the Korean Labor and Income Panel Study(KLIPS 6-17), which included 10532 employed subjects aged 55 to 75. Multi-level growth curve modeling was performed by fixed and random effect models using STATA 13.0 program. Afterwards, Hausman test was performed, which resulted in support of the estimation by fixed effect model. The results showed that a day labor position was significant factor affecting the deteriorated changes of self-rated health status over time. In addition, wage, weekly working hours, and private/relational social capitals were also found to be significant factors affecting the changes of the self-rated health status. The results supported the divergence hypothesis as well as the cumulative advantage theory. Efforts should be made to develop and implement various employment support policies and social service programs to alleviate the health inequality of the employed workers over their middle-aged to young-old period.

• Journal of Life Science
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• v.14 no.5
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• pp.761-769
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• 2004

This study was investigated the occurrence of sclerotinia rot caused by Sclerotinia sclerotiorum at the major perilla cultivating area, Gangdong-dong, Gangseo-gu, Busan in 1998. The incidence of this disease ranged from 8.1 to 28.3% at Gangdong-dong area during the growing seasons. Symptoms of the disease initially appeared damping-off of infected stems and soft-rot on the leaves of perilla. Under the relatively high humidity, abundant white mycelia of the pathogen formed on the lesion developed into black sclerotia later and the infected leaves were finally fell down. Sixteen isolates, Sl-S16, isolated from diseased lesions showing typical symptoms, and pathogenicity was tested using mycerlial disks. Among them, S2 isolate showing the most strong pathogenicity was selected and identified as Sclerotinia sclerotiorum on the basis of morphological and cultural characteristics. For biological control, an antagonistic bacteria, N4 isolate which effectively inhibited not only mycelial growth of S2 isolate but also suppress sclerotinia rot on the pot assay, was selected and identified as Bacillus megaterium according to Bergey's manual and API system., Wettable powder type, N4 formulation using B. megaterium N4 isolate was developed and estimated its control effect on perilla crops in a plastic house. As a results, N4 formulation which applied before 3 days inoculation of pathogen was effectually controlled Sclerotinia rot as the control value of 98.0%, was more effective than chemical fungicide, benomyl showing the control value of 78.0%. This is the first report of wettable powder formulation as a biocontrol agent using B. megaterium N4 against Sclerotinia rot caused by S. sclerotiorum on perilla.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.11-17
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• 2000

In an effort to produce high quality Angelica gigas in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.

• Research in Plant Disease
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• v.22 no.3
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• pp.184-189
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• 2016

To select resistant oil seed crops against two species of root-knot nematodes, Meloidogyne incognita and M. arenaria, 10 cultivars of sesame (Sesamum indicum L.) and 10 cultivars of perilla (Perilla frutescens var. japonica) were screened in greenhouse pot test. All sesame cultivars tested were resistant to M. incognita but susceptible to M. arenaria. While, perilla was resistant to both Meloidogyne species. Therefore, perilla cultivars could be used as rotation crop in greenhouse infested with both M. incognita and M. arenaria. But, sesame cultivars only can be used as a rotation crop in greenhouse infested with M. incognita but not for M. arenaria.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.292-297
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• 1995

We developed an in vitro assay method for evaluating plant growth promotion and providing an evidence that the growth promotion is rendered by growth enhancing factors. The amendment of culture filtrates of Trichoderma harzianum T95 and Gliocladium virens G872 and G872B in Murashige and Skoog (MS) agar medium enhanced the cotyledon growth of cucumber in terms of fresh weight and primary leaf area of cucumber cotyledon cuttings, of which the treatment of G. virens G872B was the most effective. The mycelial culture filtrate of G872B was more effective in the growth promotion than its conidial germling filtrate. The addition of 1% sucrose in MS mineral medium with 0.1% culture filtrates of the antagonists (T95 and G872B) was optimum for enhancing the effect of the filtrates on the growth of cotyledon cuttings in vitro. When cucumber seeds treated with G872B, Pseudomonas putida Pf3 or the G872B-Pf3 mixture were planted in a greenhouse, the rate of seed germination, biomass of shoot and root, and yield of cucumber fruits were increased, especially by G872B or the G872B-Pf3 mixture. Correspondingly, cucumber fruit yields in early to middle-cycles of harvest were significantly greater in the plots of G872B than the control and Pf3-treated plots, and the final yield was highest in the plots of the G872B-Pf3 mixture applications.

• Research in Plant Disease
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• v.24 no.2
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• pp.145-152
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• 2018

During 2015-2017, we surveyed the incidence of viral infections of tomato and paprika growing in greenhouses in Cherwon province, Korea. In 2015 and 2016, we collected leaves and fruits from tomato and paprika plants growing in greenhouses. We detected viruses in the samples collected using specific primer sets for Broad bean wilt virus 2 (BBWV2), Cucumber mosaic virus (CMV), Pepper mild mottle virus (PMMoV), Pepper mottle mosaic virus (PepMoV), and Tomato spotted wilt virus (TSWV). We detected PMMoV, CMV, and TSWV in the samples, and CMV and TSWV were the most prevalent. For the prevention of future viral diseases, we then surveyed the routes of infection by these viruses in tomato and paprika plants growing in greenhouses in Cherwon province in 2017. Leaf and fruit samples were collected from seedlings and crops two and four months after transplanting into greenhouses. As a result, we found that TSWV was transferred from seedlings to plants, and outbreaks of the virus occurred at the early stage of cultivation. On the other hand, we found that CMV was a virus indigenous to the soil of some towns in Cherwon province, and thus outbreaks of this virus occurred at the middle stage of cultivation.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.212-216
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• 2012

BACKGROUND: Green manure and graminaceousmanure crops have several benefits, such as improving soil physical and chemical properties and utilizing excessive greenhouse nutrients that they have a potential to be a water pollutant source. METHODS AND RESULTS: The objective of this study was to investigate nitrogen (N) supplying capabilities of green manure and graminaceous manure crops for lettuce (Lactuca sativa L.) and Chinese cabbage (Brassica campestris L.) grown under greenhouse conditions. For this two leguminous manures (Crotalaria juncea (Cr.) and Sesbaniaexaltata (Se.)) and two graminaceous manures (Sorghum bicolor; Haussolgo(Ha.) and Sudangrass (Sg.)) in the greenhouse were grown, cut, and incorporated into the greenhouse soil before planting. Chemical nitrogen (N) fertilizer rate was estimated based on N recommendation for lettuce and Chinese cabbage. 100% of the N recommended rates (1N) were 70 kg N $ha^{-1}$ for lettuce and 60 kg N $ha^{-1}$ for Chinese cabbage and 50% of the N recommendation rates (0.5N) were 35 kg N $ha^{-1}$ for lettuce and 30 kg N $ha^{-1}$ for Chinese cabbage. Nitrogen treatments were control (0N), Cr., Se., Cr + 0.5 N, Se + 0.5 N, Ha + 0.5 N, Sg + 0.5 N, and N recommendation rate (1N). Incorporated N from green manure and graminaceous manure crops were 130, 116, 93, and 87 kg N $ha^{-1}$ for Cr., Se., Ha., and Sg., respectively. Lettuce and Chinese cabbage were grown after incorporated green manure crops into the greenhouse soil. There was no significant difference in lettuce and Chinese cabbage yields under N treatments except control (0 kg/ha). Nitrogen use efficiency (NUE)was from 44% to 73% and the highest NUE was under Se. treatment. Although yields were not statistically different under N treatments except control, actual yield increase ranged from 170 to 1,100 kg/ha for lettuce and ranged from 2,770 to 5,210 kg/ha for Chinese cabbage compared to yield under N recommendation rate. Estimated economic benefit from this would be higher approximately between \2,770,000 and \5,210,000/ha under N treatments except control than the N recommendation rate. CONCLUSION: These results suggest that incorporating green manure crops, such as Cr. and SeSe. into soil or adding 0.5 N after incorporation of them can be beneficial in many ways in that it increases economic return because of yield increase, reduces the use of chemical N, and decreases the negative environmental impact on water quality because excessive N in the greenhouse soil can be used by green manure crops during the fallow.

• Research in Plant Disease
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• v.17 no.3
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• pp.295-301
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• 2011

The effect of various fungicides on anthracnose of strawberry, caused by Colletotrichum gloeosporioides, was determined in vitro, and in greenhouse and field trials. The $EC_{50}$ values of benomyl were clearly different between two sensitive and resistant groups of isolates. Iminoctadine tris had lower $EC_{50}$ values than mancozeb and propineb as protective fungicides and the response of mancozeb, propineb and azoxystrobin was variable depending on the isolate. In the greenhouse, pre- and post- inoculation fungicide applications significantly reduced disease compared to the non-treated control. Propineb, mancozeb and azoxystrobin were effective in controlling the disease when applied prior to inoculation. Metconazole and prochloraz-Mn treatments as ergosterol biosynthesis-inhibiting fungicides had the lowest incidence of anthracnose. In the nursery field trials in 2009 and 2010, the reduced fungicide spray program provided similar levels of disease control compared to the calendar-based applications with captan. A reduced spray program based on efficacious fungicides such as prochloraz-Mn will be useful for strawberry growers and provide more options for controlling anthracnose in Korea.

• Management & Information Systems Review
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• v.37 no.2
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• pp.87-108
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• 2018

This article explores the international trade flow of Bangladesh's ready-made garments (RMG). We first suggest the brief history and an international structure of trade among countries by using the trade volume. Then we implemented a gravity model regression with the sample of 38 major partner countries in order to investigate the potential export market for the RMG industry. The fixed effect and random effect model for the panel data during the period of 1990 to 2011 are estimated. Our result shows that Bangladesh's RMG exports are affected positively by the size of economy, inflation, exchange rate, foreign direct investment(FDI) and trade openness. On the other hand, the distance between trading partners are related negatively with the trade volume. We used the estimated coefficients from the panel regression in order to predict RMG export potential of Bangladesh. This might show which country is the promising export market for Bangladesh RMG industry. We found that Bangladesh has the highest potential of RMG export with Japan and USA, which seem to have considerable room for export growth if trade barriers and constraints are removed. We added some policy implications for encouraging the RMG export of Bangladesh by using the results from the analysis.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.163-170
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• 2012

Nineteen registered insecticides including 8 mixed formulations with buprofezin and 11 single formulations which is not including buprofezin were evaluated by spray application for their toxicity against adult and nymph of citrus mealybug, Planococcus citri. Five mixed formulations with buprofezin such as buprofezin 15EC+acetamiprid 4EC, buprofezin 10SC+clothianidin 3SC, buprofezin 20WP+dinotefuran 15WP, buprofezin 20SC+thiacloprid 5SC, and buprofezin 20SC+thiamethoxam 3.3SC showed high insecticidal activity (>93%) against nymph and adult of P. citri. Insecticidal activities of EPN 45EC, fenitrothion 50EC and methidathion 40EC in organophosphorous group showed 90 to 93% against nymph only. In addition to, insecticidal activities of acetamiprid 8WP, clothianidin 8SC, dinotefuran 20WG and thiamethoxam 10WG in neonicotinoids group showed above 90% against nymph only. In systemic and residual effect, five mixed formulations that was already proved to have high insecticidal activity showed low toxicity with below 60% against $3^{rd}$ instar nymph of P. citri in tomato and rose under greenhouse. Control efficacy of five mixed formulations with buprofezin was above 90%, 80% and 70% at 5 days after treatment (DAT), 10 DAT and 15 DAT, respectively.