• Korean journal of applied entomology
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• v.44 no.2
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• pp.157-159
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• 2005

The number of winter buds oviposited by Drycosmus kuriphilus against chestnut varieties was lower of Ishizuchi and Daap than that of Okkwang, Tsukuba and Arima. D. kuriphilus oviposited multiful eggs in each winter bud of most of the chestnut varieties tested. More than three eggs were oviposited on winter bud of lower shoot of native, Tsukuba, Okkwang and Pyounggi varieties. However, average laid eggs less than one were on winter buds of Tshizuchi and Daap. Number of eggs oviposited in winter bud on lower shoot was higher than those on upper one. More than 15 eggs were oviposited in Tsukuba, whereas one or less egg was oviposited in Daap. Rates of winter buds oviposited by D. kuriphilus in native, Arima and Tsukuba were 83.8, 78.5, and $75.9\%$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.166-176
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• 2009

Eighteen Korean chestnut cultivars were collected from various places and the proximate compositions, dietary fiber, amino acid and free sugar contents in three parts (whole kernel, white kernel, yellow kernel) of eighteen Korean chestnut cultivars were analyzed. The white kernel of Chukfa and the yellow kernel of Ipyung contained the highest amount of moisture and crude protein, respectively. Carbohydrate content of whole kernel showed a range of $30.8{\sim}52.0%$ and crude ash content of whole kernel showed a range of $0.9{\sim}1.8%$. The amount of crude lipid was the highest in Byunggo. The amount of dietary fiber in Kwangeun, Daebo, Parkmi 1 ho, Yooma and Pyeonggi were higher than that of other Korean chestnut cultivars. Seventeen amino acids were detected. Major amino acids of the various chestnuts were aspartic acid and leucine. The amount of amino acids was higher in Ichui, Ipyung and Pyeonggi but was lower in Dantaek and Sandae than that of other samples. The major free sugar in the chestnuts was glucose. The free sugar amount of yellow kernels was higher than the white kernels.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.393-400
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• 2012

Compositional changes of the Korean chestnut (Castanea crenata) including Daebo, Tsukuba, Tanzawa and Okkwang were investigated in order to characterize them from different periods (immature, mature and storage period). Proximate compositions of mature cultivars were higher than that of the immature cultivars. Between minerals, K (263.0-420.6 mg/100 g) and P (45.8-69.6 mg/100 g) of Tanzawa were highest, and they gradually increased during storage. Tsukuba, in mature period, showed the highest contents of total essential amino acids and glutamic acids as savory amino acids. Major fatty acids were palmitic acid and linolenic acid in four cultivars. In addition, linoleic acids, as ${\omega}$-6 fatty acids, were increased during the storage period. Tanzawa, in the mature period, presented the highest levels of sucrose, however, tsukuba, in the storage period, showed relatively higher free sugar content than others. ${\beta}$-Carotene, as a provitamin A, of Tsukuba in the mature period was highly detected among them, and vitamin C of Tsukuba and Tanzawa was more plentiful than others.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.398-405
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• 1995

In termperate zone planting rice at different date subjects the crop to different climatic condition. This study aimed at comparison of the change in source-sink relationship of the Japonica(J) and that of Indica Japonica(I$\times$J) type rice cultivars caused by shift of heading date. Two J-and two I$\times$J-type cultivars were made to head on Aug. 16, Aug. 26 and Sep. 5. Percent grain fertility was not changed in response to shift of heading date. Ripening patterns of 4 rice cultivars were similar to sigmoid curve type but when the heading date was delayed to Sep. 5, the form is changed to log type of curve. In J-type, physiological maturity was delayed about 5 day when headed at Sep. 5, in compare to headed at Aug. 16 and Aug. 26. However ripening was continued about 10 days when the diurnal, nocturnal and minimum temperature was above 17, 12$^{\circ}C$ and about 3~8$^{\circ}C$. In I$\times$J hybrid, real ripening was continued when the diurnal, nocturnal and minimum temperature was over 20, 17$^{\circ}C$, but if the minimum temperature was downed bellow 1$0^{\circ}C$, it was impossible. Simulated photosynthetic amount based on photosynthetic ability, temperature, leaf area and day length was varied according to changes in heading date and it was decreased seriously if the minimum temperature was fall down bellow 4$^{\circ}C$ in field, that's why decrease in photosynthetic ability and aging. The temperature range of optimum ripening was 21~26$^{\circ}C$, if there is nothing hindering factor.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.250-255
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• 1983

Newly manufactured compound fertilizers for chestnut trees developed by Chosun Fertilizer Inc. were tested to evaluate their effectiveness. An experiment was carried out in chestnut farm with 4 years old Eungi Var. from 1981 to 1982. The results obtained are as follows: 1. The growth of chestnut trees was generally good in plots of compound fertilizer contained boron (B C F). 2. The number of ripened strobiles was significantly increased by reducing the ratio of dropped strobiles in plot of B C F. 3. The yield of chestnut by B C F was markedly increased, 6 times more than that of compound fertilizer without boron. 4. Boron content in soil and plant by application of B C F was relatively high, resulting in high production of chestnut. 5. B C F was effective in chestnut orchard to increase nut production markedly.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.218-223
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• 1982

Physicochemical properties and aging of chestnut, Castanea cretana(Eungi), starch were investigated. The starch granules were irregular oval shape with the ratio of short and long axis of 1 : 1.4 and the size of $2.9-21.4{\mu}$ (average $10\;{\mu})$). The starch showed a typical B-type X-type diffraction pattern. Amylose content and water binding capacity were 22.7% and 81.5%, respectively. The optical transmittance of 0.1% starch suspension increased rapidly from $55^{\circ}C$. The swelling power of the starch repidly increased betwen $55^{\circ}C$ and $60^{\circ}C$, and its increase slowed down thereafter. Amylograms of starch at 5% and 6% concentrations indicated that the starch was stable against heat and shear force. The viscosity at 6% concentration was over twice higher than that at lower concentration. The time constant(reciprocal of rate constant) for 45% starch gel stored at $21^{\circ}C$ was 1.68 days.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.295-299
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• 2007

Resistance to chestnut gall wasp (Dryocosmus kuriphilus) of Korean prevailing chestnut cultivars, new cultivars released by Korea Forest Research Institute (KFRI), and local cultivars by growers was investigated to select optimal cultivars suitable for main chestnut producing areas. During three years investigated from 2004 to 2006, we could find no damage by chestnut gall wasp in any cultivars of test sites located in Gongju and Chungju of the central area. However, most cultivars of Gwangyang, Sancheong and Hapcheon sites located in the southern area showed a lot of damage by chestnut gall wasp. Hapcheon was most severe in comparison with regional damage by chestnut gall wasp. From comparison among cultivars, Kwangeun, Sandae, Eunsan and Idae released by KFRI showed no damage suggesting the highest resistant cultivars. On the contrary, over 20% in total damage by chestnut gall wasp was investigated in Tanzawa, Riheiguri, Kurakata-amaguri, Pyeonggi, Gwangdeok, Seil, Sinipyeong and Yumabyuni suggesting susceptible cultivars. In damage by chestnut gall wasp according to investigated position within tree, weak shoot was more severe than bearing shoot. Damage by chestnut gall wasp of major cultivars in Gwangyang, Sancheong and Hapcheon sites was remarkably decreased in 2006, and it seems to be caused by biological control by natural enemies such as Torymus sinensis.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.297-300
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• 2017

Plant factory can control artificially the environments for crop cultivation, so they can produce high quality agricultural products all year round. This study was carried to select suitable kohlrabi cultivar for hydroponics in a closed-type plant factory system. We used three cultivars of red kohlrabi, 'Asac kohl', 'Kolibri', and 'Purple king' as plant materials. The artificial light source was LED light, light intensity and photoperiod were $249{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and 12/12 hours (day/night period), respectively. Hydroponic cultivation type was used circulating deep flow technique. At 43 days after transplanting, fresh weight of whole plant and tuber and leaf area were not significantly different among cultivars. Shoot dry weight and tuber dry weight were highest in 'Asac kohl' cultivar, and number of leaves was highest in 'Purple king' cultivar. Sugar content and yield were highest in 'Asac kohl' cultivar. Considering the growth and marketable yields, 'Asac kohl' was the optimal kohlrabi cultivar for hydroponic cultivation in a closed-type plant factory system.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.239-247
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• 1982

Free and bound lipids of both inner and outer part in the edible portion of 3 varieties of chestnuts(Castanea crenata) were extracted and fractionated into neutral lipid, glycolipid and phospholipid, by silicic acid column chromatography. Fatty acid composition of each fraction was examined with gas chromatography. Lipid contents in chestnut on dry weight basis were 1.84% in inner part(1.26%-free lipid and 0. 58% bound lipid) and 1.95% in outer part (1.63%-free lipid and 0.32%-bound lipid). Free lipid content was $2{\sim}5$ times higher than bound lipid content and was more abundant in the outer part. Neutral lipid content of the free lipid in the inner part was 39.5%, approximately 10 times as much as that of the bound lipid, but in the outer part, the former was 56.6%. Glycolipid content was 22. 0% in the free lipid and 17.0% in the bound lipid. Phospholipid content was 6.9% in the free lipid and 10.5% in the bound lipid. The predominant fatty acids were linoleic acid, palmitic acid and linolenic acid in the free lipid, and palmitic acid, linoleic arid and linolenic acid in the bound lipid, Therefore, saturated fatty acid content in the bound lipid was 2 times higher than in the free lipid.