• Korean Journal of Microbiology
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• v.49 no.1
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• pp.64-70
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• 2013

The greenhouse whitefly, Trialeurodes vaporariorum, is an economically important pest for greenhouse crops because they cause direct damage by feeding on plant nutrients and indirect damage as transmits many virus vectors. It has recently become a serious problem because of the continuous use of insecticide resulting in resistance among greenhouse whitefly population. To overcome these problems, in this study, the biological characteristics and virulence of an entomopathogenic fungus isolated from the cadaver of nymph greenhouse whitefly were investigated. Isolated fungus was identified as Isaria fumosorosea by morphological examinations and genetic identification using sequences of the ITS, ${\beta}$-tubulin, and EF1-${\alpha}$ regions. This fungus was named as I. fumosorosea SDTv and tested for the virulence against nymphs T. vaporariorum and the cold activity, the thermotolerance and the stability of UV-B irradiation on conidia. Mortality rate of greenhouse whitefly showed from 84 to 100% and the virulence increased with increasing conidial concentrations, $1{\times}10^5$ to $10^8$ conidia/ml. Conidia were stable at $35^{\circ}C$, 0.1 $J/cm^2$ of UV irradiation and germinated after 8 days at $4^{\circ}C$. Additionally, the activities of chitinases and proteases produced by I. fumosorosea SDTv were varied according to the medium. In conclusion, I. fumosorosea SDTv which showed high mortality rate against greenhouse whitefly will be used effectively in the integrated pest management programs against the greenhouse whitefly.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.47-55
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• 1981

Silk textile finishing has been studied for many years by many workers in order to meet more utilities for various endusers. Such studies, however, could not be successful because any natural fibers are hardly change their natures by artificial treating methods. Textile finishing is of course to improve the mechandise qualities and the poor natures of silk so that it may be available as the best textile fiber in the world. Sometimes, famous trade marked textile plays more power than its quality in the silk market, nevertheless, this should be over line of research activities. Meantime, the silk demand has been also transferred from ladies stocking to other clothes since nylon or other synthetic fibers were developed. That is why, the extension of silk demand should be developed by various research works. Specially, silk is known as difficult textile to handle it during washing or ironing process which happened to depress down the silk usage for house wives. In order to solve such problems, the reporter has been worked for many years and now, he believes that he has developed a proper finishing method to coversuch problems. The developed finishing method may be said to eligible with economical aspect and shorten the dry duration after water washing in half against normal silk textile without harming the specific silk nature. As all of us know, silk fiber starts to denature since it was spinned by silkworm and the fiber is formed as overlapped "S" type curves during its concooning process. After it is made as raw silk or sericin silk, it shows as straight line form, but it changes in to waved form in case refining or degumming process in order return to its original spinned form. Such nature is continued during its textile form and ends with hard ironing nature than other textile fibers. Mean while, the silk fiber keeps to continue its denaturing and this is iniciated by repeat of washing and drying which takes many years to reach its final stage, The reporter has found the iniciating denature of silk by his finishing process, with out heat, decreasing the swollen nature which ended with shortening the drying duration after wash. Each washing was carried out by soaking the previously weighed sample in cold water for one hour, then pressed the sample for ten minutes to eliminate its free water component before weighing with same condition. According to this, the treated silk showed much denaturing after the finishing, but the standard silk progressed the denaturing by and by with the repeat of washing and drying, finally reached the same swollen degree of treated silk, Such treating result explains that the treated silk happened to be stebilized nature by the treating immediately. On the other that the treated silk happened to be stebilized nature by the treating immediately. On the other hand, standard silk may reach to such condition by the time of worn out clothes after repeat of washing and drying for many years while the clothes will be no more useful. The decreased swelling nature has brought about the drying period in half against standard silk after all. Not only the tests of tenacity and elongation but also crease resistance recovery, stiffness and shrinkage tests were carried out after each washing and drying which he has found better result on the treated silk textile against the standard silk. The most important thing was to keep the textile feeling of silk by such finishing work before improve any poor nature of silk. The general silk has a nature to absorb smoke or dirt from its surrounding air and reaches to dirty color shade upon such exposure, but the treated one has improved such nature because of its artificial denaturing, another word, it keeps clean longer than the normal silk. Many previous finishing works could improve some specific nature of silk, but it happened to deprave other important natures. The reporters work is, however, specialized to improve the silk to be useful as Wash and Wear Silk without harming its standard natures. So far, this work happened to be a overall innovative finishing method of silk textile.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.645-650
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• 2011

Pear cultivar 'Supergold' (Pyrus pyrifolia var. culta Nakai) was originated from the cross between 'Chuwhangbae' and 'Manpungbae' with the aims of improving the fruit quality of 'Chuwhangbae' cultivar at Pear Research Station of National Institute of Horticultural & Herbal Science, Rural Development Administration in 1994. 'Supergold' was preliminarily selected in 2002 and named in 2008. The tree shows a vigorous growth habit and semi-spread characters like as 'Manpungbae'. Furthermore, it has sufficient flowers and carries abundant pollen grains, so it can also be used as a pollinator. 'Supergold' is highly resistant to black leaf spot (Alternaria kikuchiana) in the field condition. The optimum harvest time is around Sep. 11th, which is ahead of 'Whangkeumbae' about 5 days in the harvest period. The fruit shape is oblate and fruit skin color is greenish-white at harvesting time. The average weight of fruit is 570 g, and the soluble solids content is $13.6\;^{\circ}Brix$. The flesh is very soft and juicy, and renders good eating quality. Shelf life is about 6 months under the cold storage condition. To determine the self-incompatibility (SI) genotype of 'Supergold' pear cultivar, it was crossed with other cultivars of which SI genotypes have already known. The result of cross-pollinations of 'Supergold' with other cultivars showed relatively high rates of fruit set from 64.5% to 91.0%, except for the cross with pollens of 'Nijisseiki' that represented only 28.8% of fruiting rate. Although sometimes the stigma of 'Supergold' crossed with 'Hayatama', 'Chojuro', and 'Nijisseiki' showed malformed pollen tube tips, 'Supergold' is generally supposed to have cross-compatibility with all other pollen donor cultivars. It is considered that the S-allele of 'Supergold' is $S_3S_4$, which is based on the result of PCR-RFLP.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.330-339
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• 2010

In order to suggest correct direction of researches on Miscanthus spp. which are promising bioenergy crop, authors had reviewed and summarized various literature about botanical taxonomy, morphology and present condition of breeding, cultivation and utilization of miscanthus. Among the genus of Miscanthus which are known 17 species, the most important species are M. sinensis and M. sacchariflorus which origin are East Asia including Korea, and M. x giganteus which is inter-specific hybrid of tetraploid M. sacchariflorus and diploid M. sinensis. Miscanthus is superior to other energy crops in resistance to poor environments including cold, saline and damp soil, nitrogen utilization efficiency, budget of input energy and carbon which are required for producing biomass and output which are stored in biomass. The major species for production of energy and industrial products including construction material in Europe, USA and Canada is M. x giganteus which was introduced from Japan in 1930s. In present, many breeding programs are conducted to supplement demerits of present varieties and to develop "Miscanes" which is hybrid of miscanthus and sugar cane. In Korea, the researches on breeding and cultivation of miscanthus were initiated in 2007 by collecting germplasms, and developed "Goedae-Uksae 1" which is high biomass yield and "mass propagation method of miscanthus" which can improve propagation efficiency in 2009. In order to develop "Korean miscanthus industry" in future, the superior varieties available not only domestic but also foreign market should be developed by new breeding method including molecular markers. Researches on production process of cellulosic bio-ethanol including pre-treatment and saccharification of miscanthus biomass also should be strengthen.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.4
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• pp.317-323
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• 2004

This study was carried out to determine the effect of seed method and seeding rate on the desirable agronomic characteristics and yield of forage barley(Hordeum vuigare) at paddy field, National Livestock Research Institute, RDA, Suwon from October 2001 to May 2003. The experiment was arranged in a spilt plot design with three replications. Main plots consisted of tow seed method; Broadcasting and drilling, Sub-plots consisted of seeding rates; 130. 160, 190 and 220 kg/ha. The results obtained were summarized as fellows ; The resistance of cold, disease and lodging of barley for the seeding method and seed rate were not different. And dry matter percentage of barley for a seeding method of 130 kg/ha at the broadcasting was the lowest of $32.0\%$, and that for the drilling at 130 kg/ha was $32.7\%(P<0.05). Fresh yield of barley for a seeding method of drilling at 130 kg/ha was the highest of 32,073 kg/ha, and that for a seeding method of broadcasting at 130 kg/ha was the lowest of 20,944 kg/ha(P<0.05). Dry matter yield of barley for a seeding method of drilling at 160 and 130 kg/ha were the highest 9,170 and 9,138 kg/ha, and that fur a seeding method of broadcasting at 130 kg/ha was the lowest of 5,710 kg/ha(P<0.05). Based on the results of this experiment, it appears that the seeding method and rate of barley could be enhanced by drilling from 130 to 160 kg/ha, and broadcasting from 190 to 220 kg/ha. respectively.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.143-150
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• 2003

Korea has plentiful precipitation but rainfall events concentrate on several months of rainy season in her weather condition. Korea, therefore, experiences drought for a given period every year. Moreover the soil has usually low water holding capacity, as it is composed coarse particles originated from the granite. Response of several oaks and the Korean red pine (Pinus densiflora) on water stress showed that water budget was significant factor determining vegetation distribution. In addition, dehydration level due to cold resistance mechanism of several evergreen plants during the winter season was closely related to their distribution in natural condition. Experimental result under water stress showed that the Korean red pine was very tolerant to desiccation but the seedlings showed high mortality during the dry season. The mortality tended to proportionate to soil moisture content of each site. A comparison between soil moisture content during June when it is severe dry season and moisture content of the culture soil when the pine seedlings reached the permanent wilting point due to water withheld proved that high mortality during the dry season was due to water deficit. Water potential of sample plants measured during the exposure experiment to the air pollutant showed a probability that water related factors would dominate the occurrence of visible damage and the tolerance level of sample plants. In both field survey and laboratory experiment, plants exposed to air pollution showed more rapid transpiration than those grown in the unpolluted condition. The result would due to injury of leaf surface by air pollutants. Aluminum (Al/sup 3+/) increased in the acid soil not only inhibits root growth but also leads to abnormal distribution of root system and thereby caused water stress. The water stresses due to air pollution and soil acidification showed a possibility that they play dominating roles in inducing forest decline additionally to the existing water deficit due to weather and soil conditions in Korea. Sludge, which can contribute to improve field capacity, as it is almost composed of organic matter, showed an effect ameliorating the retarded growth of plant in the acidified soil. The effect was not less than that of dolomite known in widely as such a soil ameliorator. Litter extract contributed also to mitigate the water stress due to toxic Al/sup 3+/. We prepared a model showing the potential interaction of multiple stresses, which can cause forest decline in Korea by synthesizing those results. Furthermore, we suggested restoration plans, which can mitigate such forest decline in terms of soil amelioration and vegetation restoration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4602-4609
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• 2013

In summer and winter, the difference between the temperature during the day and that during the night is high, which leads to various problems during concrete placement, such as cracks and defects in the concrete as well as low durability and strength. Although nuclear power plant concrete is widely used for placement in all seasons, particular attention must be paid to its quality during the summer. Therefore, we evaluated the effects of a cooling method for mixing water, which is a commonly used hot weather precooling method, and the use of a retarder, on the characteristics of Nuclear Power Plant concrete. In the cooling method for mixing water, cold water at 5 was used, with 50% of the water content consisting of ice flakes. The effects of using a retarder were evaluated by reviewing the characteristics of the cement at the unset stage and after hardening. To evaluate the characteristics of the unset cement, we measured the slump, air volumes, setting times, and pressure strengths after hardening. Furthermore, we measured the heat of hydration at different temperatures; the loss of heat was minimized using insulation. Both the slump time and the complete ageing time of the air volume were found to be 120 min at $20^{\circ}C$ and 40 min at $40^{\circ}C$. In the case when the cooling method for mixing water was used and in the case when a retarder was used, the initial and final sets by penetration resistance were delayed, and the delay decreased with increasing air temperature. For the heat of hydration, the cooling method for mixing water not only lowered the maximum temperature but also delayed its attainment. However, the use of a retarder had no effect on the maximum temperature. Moreover, in the early ages (e.g., 3 and 7 days), the pressure strength of the concrete was lower than that of plain cement. However, the strength of 28-day concrete met the standard construction specifications.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.606-610
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• 2011

'Jungmo1001' is an early maturing intermediate breeding line developed from a cross between Cheolweon52 and SR14694-57-4-2-1-3-2-2 by the rice breeding team of National Institute of Crop Science, Rural Development Administration (RDA) in 1994. 'Jungmo1001' has about 107 days duration from seeding to heading in mid-northern inland plain, southern alpine area and north-eastern coastal areas. It has about 73 cm in culm length with semi-erect plant type and good canopy architecture. This variety has 13 tillers per hill and 90 spikelets per panicle. Its 1,000 grain-weight of brown rice is 21.2 g which is less than 26.3 g of 'Odaebyeo'. Milled kernels are translucent with non-glutinous endosperm, low amylose content (18.1%) compared with 'Odaebyeo' palatability of cooked rice is very good. This variety shows strong resistance to cold treatment, lodging, premature heading and wilting. This variety shows moderately resistant to blast disease but susceptible to bacterial blight, stripe virus and insect pests. The milled rice yield performance of this variety is about 5.45 MT/ha by ordinary culture in local adaptability test for three years. This variety may be highly adaptable to the mid-northern inland plain, southern alpine area and north-eastern coastal areas of Korea.

• Korean Journal of Breeding Science
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• v.49 no.2
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• pp.80-86
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• 2017

'Jungmo2501' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the National Institute of Crop Science, RDA in 2010. The following is the characteristics of 'Jungmo2501' that is characterized as light green leaf, yellow brown culm and whitish yellow grain. The heading date of 'Jungmo2501' was about 3 days earlier than that of check cultivar 'Samhan'(May 7 and May 10, respectively). Its plant height was 11 cm longer than 103 cm of the check, and the leaf blade ratio of aerial parts was 26 % higher than the check (11.8% and 9.4%, respectively). The cold tolerance, resistance to lodging and wet injury of 'Jungmo2501' were similar to those of the check. The average forage dry matter yield of 'Jungmo2501' harvested at milk-ripe stage was 5% higher than the check ($15.5ton\;ha^{-1}$ and $14.7ton\;ha^{-1}$, respectively). 'Jungmo2501' was higher than the check in terms of protein content (6.6% and 5.9%, respectively), neutral detergent fiber (58.5% and 57.6%, respectively), and acid detergent fiber (34.5% and 32.1%, respectively), while total digestible nutrients was lower than the check (61.6% and 63.6%, respectively), and TDN yield was $0.37ton\;ha^{-1}$ more than that of the check ($9.71ton\;ha^{-1}$ and $9.34ton\;ha^{-1}$, respectively). The silage grade of 'Jungmo2501' estimated by Flig score showed level II, meaning good quality. Fall sowing cropping of 'Jungmo2501' is recommended only for areas where average daily minimum mean temperatures in January are higher than $-6^{\circ}C$.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.611-615
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• 2011

'Manjong' is a new japonica rice cultivar developed in 2009 derived from a cross between 'Yeongdeog34' and 'Nampyeongbyeo' at the Department of Functional Crop, NICS, RDA. This cultivar is suitable for the double cropping system after the cash crop cultivation. Heading date of 'Manjong' is later than 'Keumobyeo' under the late transplanting cultivation on July 10. It has high grain fertility under cold conditions and low premature heading. One of the distinguishing characteristics of this variety is its resistance to major diseases like leaf blast and rice stripe virus disease. However, it shows susceptibility to major insect pests and bacterial blight disease. Milled rice kernels are translucent with non-glutinous endosperm and have 7.2% protein and 18.7% amylose contents. Ripening ratio and head rice ratio is very higher than those of 'Keumobyeo'. The palatability of cooked rice is also better than 'Keumobyeo'. The milled rice yield of 'Manjong' in local adaptability tests after harvest of the cash crop is $4.81MT\;ha^{-1}$. This cultivar is suitable for planting in the plain paddy fields of Honam and Yeonnam regions in Korea.