• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.634-641
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• 2014

In order to elucidate the ecological and phenological responses of bean under global warming situation, we investigated leafing and flowering phenomena and growth traits of Baktae and Seomoktae in control plot (ambient $CO_2$ concentration and temperature) and warmed plot (elevated $CO_2$ concentration and increased temperature than control) in green house. Average $CO_2$ concentration and temperature were set 540 ppm in treatment and higher $2.2^{\circ}C$ in treatment than control. The appearance of leaf unfolding and the initiation of blooming and fruit maturing in Seomoktae were late in treatment than control. In case of Baktae, the number of total pods and seeds per plant in treatment was fewer than that in control. For Seomoktae, the number of total pods per plant and weight of total seeds per plant were decreased in treatment than in control. Thus, the number of pods and seeds of Baktae declined and the production of Seomoktae was decreased under global warming condition. This result indicates that site selection and crop yield for cultivating of the bean may be changed into new area due to global warming condition.

• Journal of Sericultural and Entomological Science
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• v.45 no.2
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• pp.112-115
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• 2003

NIAST has developed the artificial cultivation technique of entomopathogenic fungus, Isaria sinclairii by using the silkworm. NIAST is planning to provide the silkworm farmers the guidance of the technique. Screening of pharmacologically active principles of I. sinclairii is needed to register the fungal breeding, attain the approval of food materials, and ultimately position the fungus as a high value-added product. The result of investigating the characteristics of Isaria sinclairii was showed that conidia were irregularly long oval-shaped and measured 6.33$\times$3.33 $\mu\textrm{m}$ in average The optimal condition of cultivating hyphae was pH 5.0 in acidity and 21- $25^{\circ}C$ in temperature. And the best condition of producing conidia was pH 6.0 in acidity and 16-$20^{\circ}C$ in temperature.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.174-182
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• 2018

Background: In this study, we observed their growth and physiological responses using a variety of duty ratio under the mixed light using red, blue, and white lights. The red+blue mixed light was treated with 95%, 90%, 85%, 80%, and 75% duty ratios and red+blue+white mixed light with 85% and 70% duty ratios. We examined the width and length of leaves, total number of leaves, and number of shoots to examine their growth responses. The physiological responses were studied by measuring their photosynthetic rate, transpiration rate, stomatal conductance, water use efficiency, chlorophyll content, and fluorescence ($F_o$, $F_m$, and $F_v/F_m$). Results: We found that lower duty ratio caused the length and width of the leaves to grow longer under red+blue mixed light but that it did not cause any difference in the red+blue+white mixed light condition. In addition, there was no difference in the number of leaves and shoots among all treatments. In the red+blue mixed light condition, the photosynthetic rate was no difference, but both transpiration rate and stomatal conductance were the highest at 95% duty ratio than in other ratios. Water use efficiency pattern was similar to that of photosynthetic rate; water use efficiency was no difference. Chlorophyll content was the highest at 95% duty ratios, and it was the least at 90%, 85%, and 75% duty ratio. $F_o$ and $F_m$ values were relatively high at 85% and 80% duty ratio and low at 90% duty ratio while $F_v/F_m$ showed no difference. Conclusions: Under the red+blue+white mixed light, all physiological items showed no difference between 70 and 85% treatments. But, photosynthetic rate, water use efficiency, chlorophyll content, and $F_v/F_m$ were relatively greater in the red+blue+white mixed light than in the red+blue mixed light. Therefore, red+blue+white mixed light treated with 70% duty ratio could lessen the environmental stress and save more power when cultivating Silene capitata in a plant factory.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.228-234
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• 2004

In organic farming, nutrients for the crop production are mostly supplied by compost containing various organic materials. The long-term organic cultivation would result in continuous changes of soil chemical properties and fertility. The aim of this study was to investigate the contribution of long-term organic cultivation to the soil fertility in Korea focusing on the chemical properties of soil. Soil samples were collected from organic farms that had been cultivated for 8-10 years after certification of organic product through the conversion periods of 2-3 years. Thereby each organic farm had acquired optimal cultivating techniques and soil condition. We separated organic farms into three groups by cultivating crops, i.e. leaf vegetables, fruit vegetables and fruit trees. In each group, five representative farms were chosen in order to investigate the relationships between application rate of compost and nutrient contents in soil. The application rate of compost was approximately $10-15Mg\;10a^{-1}$ for the first 2-3 years at the beginning of organic farming and then reduced to a rate of $3-4Mg\;10a^{-1}$ after stabilization of organic matter content in soil with $30-50g\;10a^{-1}$. However, the continuous organic farming for 8-10 years resulted in accumulation of nutrients, especially of P, in soil probably due to the excessive amounts of compost applied. In conclusion, we suggest that the application rate and organic sources of compost should be decided on the basis of P content in soil by soil testing and thereafter the lack of soil N content for crop cultivation should be compensated by crop rotation with such as legumes. This might be an approach to the original meaning of organic farming as an environmental friendly agriculture.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.369-375
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• 2009

A commercial egg parasitoid, Trichogramma sp. Nabis101, was released into agricultural cultivating areas in Korea due to its wide host spectrum against insect pests. Moreover, an application technique has been recently developed to enhance its control efficacy by mixture treatment with a microbial control agent. Despite its expansion of commercial availability, any genetic identification on this commercial strain was not determined. Also, to meet inconsistent demands from consumers, the live parasitoids need to be stored without significant loss of their survival and parasitic activity. This study determined nucleotide sequence of internal transcribed spacer (ITS) of the wasp species. The identified ITS sequences indicate that this wasp species is most similar to T brasiliensis. Optimal storage condition of this wasp required young parasitized stage at $10^{\circ}C$. Under these conditions, survival, sex ratio, longevity, and parasitic behavior were not much impaired for 5 weeks.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.85-92
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• 1969

The goal for the improvement of rice culture in our country is to increase the rice yield per unit area, and that thoroughly, to equalize the rice yield per unit are highly by adaptation of high technique, while on the side of the efficiency, to increase the productivity of the labour through the cooperative work. And then, the theory for execution of the cooperative rice culture which is the productive system embodying the goal above and the expected effects as well as the future prospect for the development of the cooperative rice culture must be studied and defined. The results studied up to now are summarized as follows: 1. The cooperative rice culture is one of the most effective ways to execute highly efficient farm management and to supply the technical details on the cultivation for equalized high yield per unit area in the rice cultivating districts. 2. For the most effective accomplishment of the cooperative rice culture, the water control, and soil and variety of rice must be investigated in advance an then the basic technical details for the rice culture must be defined. 3. The rice cultivation calender is drawn up with the main technical details of rice culture by the mutual agreement of all farmers belong to the cooperative farm. All technical details for the rice cultivation in the cooperative farm are standardized by the rice cultivation calendar and the main technical operations should be worked together and the other operations executed individually. 4. The technique for rice cultivation, which was difficult to be introduced in the individual farm management, could be introduced easily to the cooperative rice culture, and the rice yield of the cooperative farm was increased 23.3% compared to that of common farm in 1968. 5. At present, the type of the cooperative rice culture is a primary type of the agreement for farm management, rarely including the associated operation type and the contracted operation type for a part of operation, However, for stabilized high yield through the mechanization of the cultivation system, the cooperative farm must be developed for a course promoting the associated operation type including the technique trust type and the contracted operation type according to the condition of location.

• Journal of Life Science
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• v.12 no.6
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• pp.708-714
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• 2002

A new leaf blight was found on the perilla leaves at the major perilla-cultivating areas such as Kangdong in Busan and Miryang in Kyungnam province. Symptoms of the disease initially appeared on the edge of perilla leaves showing black necrosis and drying, and the infected leaves were finally fell down. The SD1 isolate showing strong pathogenicity and forming abundant conidial spores on the diseased lesions was isolated. Among the tested media, mycelial growth was abundant on PDA (Potato Dextrose Agar) medium at $25^{\circ}C$ under dark condition, but conidial formation was greater on V8A (V-8 juice A8ar) medium than that on PDA medium. Optimal temperatures for mycelial growth and conidial formation on PDA medium were respectively $25^{\circ}C$ and 3$0^{\circ}C$. The rate of conidial germination and the elongation of germ tube were more effective in 10% tomato juice than those in PDB (Potato Dextrose Broth) and sterile water. In 10% tomato juice, the rate of conidial germination and the length of germ tube were 100% after incubation for 24k and 535.2${\mu}{\textrm}{m}$ after incubation for 36hr, respectively. According to the result of pathogenicity, it revealed that conidial suspention with 10% tomato juice was the most effective for pathogenicity test showing as 100% of disease incidence, and the symptoms caused by artificial inoculum were same as those of naturally infected perilla. In this study, the SD1 isolate according to the results of morphological characteristics, the incubation characteristics and pathogenicity was firstly identified A. alternata, and named as leaf blight of perilla.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.1
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• pp.11-21
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• 1986

The study was performed to investigate the effects of gaseous imission of sulfur dioxide and hydrogen fluoride on the growth of rice plant under stressed field conditions. The plants were cultivated in normal paddy fields where are 88 industrial plants operating with 285 smoke stacks emitting pollutants. There has been a number of reported studies (1, 3, 11, 19, 20) which deal with rice plant damages by air pollution under a simulated exposure experimental condition. Furthermore, these experiments were conducted to examine effects of a single pollutant on the plant. Furthermore, these experiments were conducted to examine effects of a single pollutant on the plant. In korea, however, there is no study reported in literature with respect to the in-situ dose-response relationship between rice pant reduction in yields and air pollution. This study is specifically dealt with multiple effects of sulfur dioxde and hydrogen fluoride on various plant growth indicators such as leaf damage, culm height, weight of grain, panicles per hill, spikelets per panicle and percent fertility.It appears that there is a good correlation between ambient concentrations of sulfur oxides and sulfur contents found in leaves with an average correlation coefficient of 0.868 within a 1% significance level. It is interesting to note that a better multiple correlation was found between percent leaf damage and sulfur and fluoride contentd found in leaf with a significance of 1% level. The yearly correlation coefficient ranges from 0.963 to 0.987 with an average being 0.971. It is, therefore, believed that a percent leaf damage may serve as a single indicator of pollutional damages to rice plant cultivating in fields. Regarding other factors to the diminution of rice plant growth in polluted atmosphere, it appears that a significant correlation to culm length and dry weight of grain with a 1% significance level whereas T/R ratio has a good correlation with lead damage within 5% significance level. An evaluation of data observed has demonstrated that both panicles per hill and percent fertility are significantly affected by air pollutants. As expected, hydrogen fluoride has more effects than sulfur oxide. It is, however, interesting to note that spikelets per panicles has slightly been affected while no indication of effects on 1000-grain-weight has been observed. This may lead to a conclusion that a reduction in yield of rice under polluted field conditions may have more been caused by the diminution of panicles per hill and percent fertility rather than by the diminution of spikelets per panicle and grain weight.

• Journal of Mushroom
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• v.5 no.1
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• pp.13-20
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• 2007

Analysis of genetic characteristics of Flammulina velutipes showed that strains have a range of 85% in genetic distribution diagram. According to this result, we divided these strains into five groups. In experiment of determinating the optimum media and condition in cultivating F. velutipes, we found the optimum temperature and pH range for hypha growth were $25^{\circ}C$ and 6.0 to 7.0, respectively. in addition, the best media for growth of that in plate was MCM (Mushroom Complete Media) which have a growth length from 68 to 83 mm. In vivo test, we observed that fast growth and good density of hyphae in mixture media of douglas fir sawdust, cotton seed meal and beet pulp (6:2:2 V/V). Also when we cultivated F. velutipes in this media, we harvested high yield of fruiting body.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.53-60
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• 2015

Newly, nutrients recovery by bioconversion in the swine waste which caused serious problems due to its high organic fraction and content of nutrients such as phosphorus and nitrogen is viewed as a considerable approach since it produces valuable product as well as recycling of resources. Consequently, it is necessary to find new methods to treat swine waste. One possible solution to this problem is to use this potential pollutant as a growth substrate for economically valuable products. The study for the fundamental improvement of bioconversion efficiency by finding optimum growth conditions using statistical models and biotechnology was performed. A novel approach to utilize swine waste by cultivating mycelia of the mushroom Phellinus linteus are described. A central composite face-centered design (CCF) for the experiments was used to develop empirical model providing a quantitative interpretation of the relationships among the three variables, which were substrate concentration, pH, and temperature. The maximal radial extension rate (2.78mm/d) of P.linteus was determined under the condition of 5.0 g COD/L, pH 5.0, and temperature $29.7^{\circ}C$. The results of this study suggest that swine waste could be utilized as a growth substrate for the cultivation of mushroom mycelia enhancing an efficiency of utilizing this by-product of the livestock industry.