• The Journal of Natural Sciences
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• v.8 no.1
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• pp.71-80
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• 1995

This experiment was conducted to investigate the effect of raising seedling methods of cold water, low night temperature, and abandoned mine on forcing culture of strawberry. The results were as follows ;1. $17^{\circ}C$ cold water alone and cold water plus 8-hour short day treatments significantly accelerated the flower bud differentiation of Nyoho cultivar to 11 and 15 days, respectively, comparing to common soil raising seedling.2. The date of flower bud differentiation of Nyoho cultivar as influenced by cold water treatment the 17th, the 13th and the 10th of September, respectively, when the seedlings were treated on the 10th of September and on the 25th and the 10th of August in 1991. In 1992, data showed that the flower bud differentiation dates were the 4th and the 2nd of September and the 29th of August when cold water treatment was done on the 10th of August and on the 25th and the 10th of July.3. The first harvest date when Nyoho cultivar was treated by cold water for 30days from Jul. 25 was Nov. 10, this implying that the harvesting day could advanced to 19 days comparing to that by the common soil raising seedling method. The resulting yield was recorded to 21.94 ton per hectare.4. Regardless of the starting date of the treatment, $13^{\circ}C$ low night temperature plus 8-plus short day treatments for 20 days required 17 days to differentiate the flower bud of Nyoho cultivar. Harvesting day could be advanced to 59 days comparing to that by the common raising seedling method when the seedling was treated on July 25, this resulting in increasing the total yield obtained by April 14 of following year to 8.25 ton per hectare.5. When the seedlings of both Nyoho and Hokowase cultivars were raised under the condition of abandoned mine, flowering and harvest date were earlier by the treatment for 20 days than that for 30 days or 40 days. The highest yiesd obtained was recorded in Nyoho cultivar or 1.88 ton per hectare.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.199-205
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• 2005

Seasonal occurrence and ovarian development of the bean bug, Riptortus clavatus Thunberg (Heteroptera: Alydidae), were studied at a soybean field and an university campus in which host plants are less available for the bug in Gyeongnam province with aggregation pheromone traps in 2004. It was assumed that the bug passed three generations per year at the university campus. Adults of the 1st generation might occur from early July to early August and that of the 2nd one from mid August to late September. Adults of the 3rd generation occurred from early October to mid November, entered reproductive diapause without carrying eggs in the ovaries of females during winter, and resumed activity from late March of the next year. Full-grown eggs in the ovaries of the overwintered females were first observed at the 1st half of May. Two peaks of occurrence, from early August to mid September and from mid October to mid November, were shown at soybean field that was sowed on May 24. The two peaks almost corresponded to those of the 2nd and 3rd generations at the university campus, respectively.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.783-788
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• 2005

Major components and antioxidative properties of whole fruit powders and juices prepared from premature mandarin, Citrus unshu, were investigated. Dietary fiber, flavonoid, and organic acid contents greatly increased in samples with lower degree of fruit maturity (August) than higher ones (October), and in whole fruit powders than extracted juices, whereas free sugar contents, especially sucrose content, increased in fruits with higher degree of maturity than lower ones. Antioxidative properties were not affected by degree of fruit maturity, whereas total polyphenol content and electron-donating abilities were higher in extracted juices than whole fruit powders. Nitrite-scavenging abilities of all samples were similar except at pH 6.0.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.120-124
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• 1995

The study was conducted to investigate the relationships between tobacco leaf pro-duction rate by quality grade and the value of climatic factors in tobacco growing season. In flue cured tobacco（NC82）, high quality was positively corretated with precipitation in late April and May, with sunshine' hours in early May and late June, with average temperature in middle July, significanly. In Burley tobacco（Br21）, high quality was positively correlated with precipitation in late April and May, with sunshine hours in early May and early July, with average temperature in middle July, significantly.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.151-155
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• 1999

Biological control of Tetranychus kanzawai by Phytoseiulus persimilis on the Angelica utilis was done in 'walk-in' plastic tunnels. The population of T. kanzawai nymphs and adults per 4 cm2 in damaged leaf decreased from 25 mites on July 22 after 25 predatory mites per m2 were released on July 23 to 0.4 mites on September 9 and then rose to 9.3 mites on October 16, 1997. Phytoseiulus persimilis could suppress T. kanzawai to low population level from August 13 to October 1.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.186.1-186
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• 2003

온주밀감의 당도를 높이고 신선도를 유지하기 위하여 무가온 비닐하우스에서 이듬해 2-4월에 수확하는 월동감귤은 부피과의 발생이 쉽고 저장성이 나빠 수확시기에 바로 출하하는 감귤을 제외하고는 저온저장이 필수적이다. 2월 하순에 수확한 월동감귤(궁천조생)을 저장 전에 키토산과 칼슘처리를 하고 저장에 미치는 영향을 검토하였다. 부패과 발생은 저장 30일부터 나타났고, 무처리에서는 그 이후 부패가 빠르게 진행되었다. 그러나 베푸란 또는 키토산과 칼슘 처리에서는 저장 60일까지 부패과의 발생을 억제할 수 있어서, 이 기간까지가 저장이 가능한 기간으로 보인다. 중량감소는 11월 하순에 수확한 궁천조생에 비하여 모든 처리에서 중량감소가 빠르게 진행되었다. 유리당은 11월에 수확한 궁천조생과 비교하였을 때 glucose은 비슷하였으나, sucrose, fructose은 다소 많은 양이 검출되었다. 유기산은 citric acid과 malic acid 2종류가 검출되었으며, 그 함량도 관행수확기에 수확한 감귤보다 citric acid는 1/2 이하로 낮게 나타났고, malic acid는 비슷한 함량이 나타났다. 저장기간이 경과함에 따라 유기산 함량은 서서히 감소하였으나, malic acid은 초기에 감소되었으나 3월 중순이후에는 일정한 수준을 나타났다. 유리아미노산의 함량은 11월에 수확한 궁천조생에 비하여 D,L-$\alpha$-aminoadipic acid, $\alpha$-amino- $\beta$-guanidinopropionic acid 등 2종을 제외한 27종이 검출되었다.

• Journal of Plant Biology
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• v.28 no.2
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• pp.119-126
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• 1985

The productivity and growth pattern of Sargassum confusum (Phaeophyta, Sargassaceae) was investigated in Ohori, east coast of Korea, from March 1983 to April 1984. S. confusum shows an obvious seasonal variation of the growth by passing through the germinative, vegetative, reproductive and decaying phases for about an year. The mean length of tagged individuals shows a positive correlation with the water temperature during the growing period. The growth is depressed at less than 1$0^{\circ}C$ in February, and accelerated at above 15$^{\circ}C$ in May. The rapid growth (1.29 cm/dry) occurs at 15-l8$^{\circ}C$ during May-June and the maximum length is shown at 20-21$^{\circ}C$ in early August. Daily net production estimated by the oxygen light and dark bottle method is 11.2 g C/$m^2$/ day in June. The annual value calculated by the integration of the daily net production, growth rate and biomass is 745 gC/$m^2$/yr. Net production estimated from the biomass change only is 287 gC/$m^2$/yr. But this must be an underestimated value, because the loss of considerable biomass by shedding is not included.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.04a
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• pp.87-91
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• 1999

봄철 하우스 수박 무가온 조숙재배에 알맞는 보온방법을 개발하고자 아취형 단동하우스에 PE필름터널, 유공필름＋축열물주머니, 유공필름터널＋부직포터널구를 처리하고, 삼복꿀수박을 '98년 3월 23일 정식하여 4월 27일까지 36일간 터널피복재의 보온성을 검토한 결과는 다음과 같다. (1) 보온재 피복 재배 기간중 터널내 최저온도는 PE터널구 10.9$^{\circ}C$에 비하여 유공필름터널에 축열물주머니구와 부직포터널구는 각각 0.9, 2.1$^{\circ}C$ 높았다. (2) 3월하순 활착기의 하우스내 일사량은 실외 175.2w/$m^2$ 비하여 124.2w/$m^2$로 51w/$m^2$ 낮았다. (3) 터널피복재 환기작업에 따른 소요 노동력은 PE터널구 25.2시간/10a/36일에 비하여 유공필름터널＋부직포터널구는 32.4시간으로 7.2시간/10a/36일 증가하였으나, 유공필름터널＋축열물주머니는 개폐작업으로 인한 투하 노동력이 없었다. (4) 터널재배 기간중 유공필름터널＋부직포터널구가 초기생육이 촉진되었으며, 생육후기에 발생한 흰가루병 이병엽율은 2.8%로 현저히 감소하였다. (5) 수박의 수확기는 PE필름터널구 6월 22일에 비하여 유공필름터널＋축열물주머니와 부직포터널구는 6월 12, 15일로 7, 10일 앞당겼으며, 수량은 PE터널구 2,385kg/10a에 비하여 20, 32% 각각 증수하였다.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.385-391
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• 2010

This study reports the results of natural enemy application against four insect pests on greenhouse sweet pepper in winter cropping system. Orius laevigatus ($3.3/m^2$) was released at two different times (Nov. 2005 & Feb. 2006) to control Frankliniella occidentalis, western flower thrips (WFT). Throughout the cropping season, the lowest level recorded of WFT was less than 2.0 individuals per yellow sticky trap. Amblyseius swirskii ($232.3/m^2$) was released four times (Nov. 2007 ~ Aug. 2008) to control Bemisia tabaci, tobacco whitefly (TWF). Until July 2008, TWF population had been suppressed lower than 6.6/trap. Phytoseiulus persimilis ($44.5/m^2$) was released seven times (Apr. 2008 ~ Aug. 2008) to control Tetranychus kanzawai, tea red spider mite (TRSM). As a result, TRSM population was suppressed lower than 1.7/1eaf. To control aphids, Aphidius colemani ($9.5/m^2$) was released seven times (Oct. 2004 ~ Jan. 2005), with the transplantation of banker plants ($5.5pot/660m^2$). As a whole, aphid's population has been successfully reduced to less than 2.0/leaf.

• The Korean Journal of Ecology
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• v.24 no.5
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• pp.315-322
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• 2001

Seasonal production and nutrient concentrations of mushrooms in an Quercus acutissima forest were studied from 1999 to 2000. Thirty 2×2m quadrats were established randomly in the study area. 114 species of mushrooms were identified during the study period. Although mushrooms occurred from May to November in each year, the highest biomass production occurred in August. Seasonal dominant species was Lactarius violascens in June, R. bella and L. violascens in July, Marasmius siccus in August, Cortinarius tenuipes in September, Lepista nuda and C. tenuipes in October, respectively. Annual production of mushrooms in 1999 and 2000 were 84.8 kgDW·ha/sup -1/·yr/sup -1/ and 86.7 kgDW·ha/sup -1/·yr/sup -1/, respectively. Seasonal production was27.1kg/ha for July, 35.9kg/ha for August and 17.1 kg/ha for September, 3.7kg/ha for October, respectively. Seasonal dominant species in biomass was Russula alboareolata in June, R. bella in July, R. pseudodelica in August and September, Lepista nuda in October, respectively. R. pseudodelica showed the highest biomass in the study area, which is 17.5% of the total biomass. Average concentration of nutrients in mushrooms was 45.2mg/g for N, 1.5 mg/g for P, 29.6 mg/g for K, 0.2 mg/g for Ca and 0.8 mg/g for Mg, respectively, which were much higher than those in the leaf litter. Nutrients absorbed by mushrooms in 2000 was 4,163.1 g·ha/sup -1/·yr/sup -1/ for N, 130.1 g·ha/sup -1/·yr/sup -1/ for P, 2,568.2 g·ha/sup -1/·yr/sup -1/ for K, 12.4 g·ha/sup -1/·yr/sup -1/ for Ca, 68.5 g·ha/sup -1/·yr/sup -1/ for Mg, respectively.