• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.229-234
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• 1989

In flue-cured tobacco, the relationships between the quality of tobacco leaves (productivity according to quality grade) and specific meteorological factors were noted showing different significances according to different seasons during the growing period of the tobacco plants. The thick leaf high quality was significantly correlated with average temperature in late April, late May, early July and late July. The degree of contribution was greatest in middle May and lowest in late May. In the highest and lowest temperatures, the relations to leaf quality had similar tendency like in the average temperature; the thick leaf low quality showed opposite tendency relative to the high quality in the degrees of correlations and contributions. Amount of precipitation was significantly correlated with the thick leaf high quality in late April, early May, middle May, late June and late July. The degree of positive contribution was shown in order of late April, middle July and early July, and that of negative one was in order of middle June, early June and late June, respectively. Duration of sunshine period was highly associated with thick leaf high quality of tobacco leaves in all of the growing season except for middle April and middle July. The degree of positive contribution was in order of late May, late April, early July and middle July, and that of the negative one was in order of late June, early May, middle June and middle May.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.2
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• pp.109-116
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• 2012

This study was carried out to determine the forage quality, production, and regrowth of Phragmites communis as a native grass according to growth stages. Experiment 1 was conducted in Ansan from May 2009 to April 2010 (7 stages), and experiment 2 was conducted in Cheonan from May to November 2011 (10 stages). In experiment 1, forage quality decreased rapidly with advance of growth from May. When harvested on late May, July, September and April of the following year, the contents of crude protein were 7.7%, 4.6%, 3.7%, and 2.2%, respectively. Relative feed value (RFV) were 80.2, 65.1, 61.8 and 52.8, and lignin contents were 7.1%, 9.9%, 12.0%, and 13.2%, respectively. In experiment 2, significantly higher forage yields were observed when harvested from late June to mid July. On the other hand, forage quality decreased with delayed harvest as was in experiment 1. Good regrowth of Phragmites communis was observed when harvested earlier than in August. When harvested on late May, June, July, August, September, October and November, the dry matter (DM) yields were 7,329 kg/ha, 12,527 kg, 9,593 kg, 8,279 kg, 7,649 kg, 5,822 kg and 5,540 kg, and in vitro digestible DM (IVDDM) yields were 3,924 kg/ha, 5,264 kg, 4,273 kg, 3,322 kg, 3,352 kg, 2,195 kg and 1,887 kg, respectively. Forage quality grades of Phragmites communis were 4th grade in May, 5th grade from June to Sept., and 6th grade in Oct., Nov., or in Apr. of the following year. However, all regrown Phragmites communis ranked the 4th in quality. In conclusion, we recommend that Phragmites communis should be harvested from late June to mid July (no later than the end of July) to obtain good forage quality with digestible nutrient contents greater than rice straw. Regrowth of Phragmites communis was poor, and more than 70% of annual forage yields were out of the first harvest. Therefore, we recommend only one harvesting per year for good regrowth and stable production of Phragmites communis.

• Journal of Life Science
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• v.13 no.2
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• pp.206-213
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• 2003

This study was conducted to estimate volatile compounds in pericarp of Zanthoxylum piperitum DC (Chopi). Chopi which harvested on lune 2, July 14 and September 11 in 2001 was dried at room temperature for one week. Fifty-two, 47, and 44 volatile compounds were analyzed with GC-MS in pericarp harvested on lune 2, July 14 and September 11, respectively. Eight terpenes including myrcene, ${\gamma}$-terpinene, $\alpha$-terpinolene, $\alpha$-phellandrene and $\beta$-caryophyllene were detected in pericarp harvested on tulle 2 and July 14, but not $\alpha$-phellandrene and $\beta$-caryophyllene in pericarp harvested on September 11. Thirteen alcohols or terpene alcohols including linalool L and citronellol were detected in pericarp harvested on lune 2, and added cis-linallol oxide and piperitol isomer in pericarp harvested on July 14 and September 11. Three aldehydes or terpene aldehydes were not affected by degree of maturation, but citronellal was increased in pericarp harvested on September 11. Five volatile compounds of ketones containing cryptone and piperitone were detected, and their concentration was changed during maturation. Six esters including lavandulyl acetate and $\alpha$-terpinenyl acetate were detected in pericarp harvested on lune 2, and [(E)-6,7-ephoxy-3,7-dimethyl-2-octenyl]ester of acetic acid was added in pericarp harvested on July 14 and September 11. Seven hydrocarbons including $\delta$-cadinene and neopentylidene cyclohexane were detected in pericarp harvested on June 2 and $\alpha$-muurolene was newly added in pericarp harvested on July 14 and September 11. We suggest that kinds and concentration of volatile compounds in pericarp were remarkably different from those in mature stage.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.117-117
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• 2003

다시마(Laminaria japonica) 생태육종 연구의 일환으로 완도산과 백령도산 품종의 재배시험을 전남 고흥군 명천어장과 계도어장에서 2001년부터 2002년까지 실시하였다. 시험기간 중 어장의 수온, 염분농도, 유속, 용존산소농도는 구간별로 유의차가 없었으며 수온은 1월부터 7월까지 점차 상승하였고, 염분농도는 5월까지 상승하다가 6월과 7월에 낮아졌다. 유속은 저층에서보다 표층에서 빨랐고, 용존산소농도는 1월부터 7월까지 점차적으로 낮아졌다. 어장의 영양염 변화는 구간별로 1월부터 7월까지 유의차가 없었으며 암모니아염이 5월에 다소 증가하였다. 일반적으로 전장과 엽폭은 4월까지 증가하다가 끝녹음으로 인하여 4월이후에는 다소 감소하였으나, 엽두께, 전중량, 비대도는 7월까지 계속적으로 증가하였다. 형질간의 상관관계는 모두 1%와 5% 수준에서 유의차가 있었다. 각형질에 있어서 품종과 환경간에 월별로 질적교호작용과 양적교호작용중 어느 한 쪽이 나타났다. 품종시험에 의한 유전력은 엽폭에서 가장 높았고, 엽두께에서 가장 낮았다. 표현형상관, 유전상관, 환경상관계수는 형질간에 대부분 높은 값을 보였으나 엽두께와 전중량간의 값이 일반적으로 낮았다. 부모와 자식간의 회귀에 의한 유전력은 계도어장의 엽두께에서 가장 높았으나 일반적으로 전중량에서 높았고, 육종가와 유전상관은 전중량에서 가장 높았다. 각 형질의 상대적 경제 가치를 고려한 선발 총점은 명천어장에서의 완도산 품종에서 가장 높았다.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.75-87
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• 2018

This study was carried out to investigate the effects of planting time on the survival rate and growth. Ilex cornuta Lindl., I. aquifolium 'Silver Queen', Ardisia pusilla 'Variegata', and Rhododendron indicum(Satsuki azalea) were planted in pottery pot six times such as April 1, June 1, July 1, August 1, October 1, and December 1 in 2017. The survival rate of I. cornuta Lindl. planted in April, October, and December was 100%, whereas the survival rates were 90% in June, 50% in July, and 60% in August, respectively. The survival rates of I. aquifolium 'Silver Queen' and R. schlippenbachii were also shown about 60% in July and 70% in August, which were lower than in the other planting times at 100%. However, the survival rate of A. pusilla 'Variegata' was shown 100% in the all planting times. The growth rates of plant length, plant height or leaf length or any others of I. cornuta Lindl. were shown 20.0%, 15.5% and 16.5% planted in June, July, and August, respectively, while those planted in April, October and December were 3.2%, 12.3% and 10.7% respectively. Similarly, the growth rates of leaf numbers and plant length of I. cornuta Lindl., A. pusilla 'Variegata', and R. indicum(Satsuki azalea) planted in summer season from June to August for all plat (not only leaf numbers and plant length in was facilitated, while the growth was restrained in planting for spring or autumn. Therefore, the plantation during summer is better for increasing the survival rate and promoting the growth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.95-101
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• 1980

Optical properties were studied at the fishing ground of anchovy in the southern part of Korea based on seven oceanographic stations from May to August and November to December, 1977. Submarine daylight intensity was measured at intervals of 1m depth in the upper 30 m layer by the underwater luxmeter (Toshiba # 9). The absorption coefficient of the sea water ranged from 0.066 to 0.619 (mean 0.21) for six months. The transparency ranged from 2.6 to 16 meters (mean 8.4m). The relationship between absorption coefficient (n) and transparency (D) was k=1.70/D. The mean water color in this area was 4.8 $(3\~10)$ in Forel scales. The rates of light penetration for daylight at four different depths were computed with reference to the surface light intensity. The mean rates of light penetration were $69.38\%(25.43\~88.10\%),\;30.35\%\;(4.38\~59.46\%),\;12.53\%\;(0.75\~33.51\%),\;5.7\%(0.18\~20.27\%)$ at depths of 1, 5, 10 and 15 m respectively.

• Asian Journal of Turfgrass Science
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• v.24 no.1
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• pp.16-23
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• 2010

Mowing is an important practice in golf course management. Mowing interval and height can affect net photosynthesis of turfgrass and finally shoot density, tillering, rooting and regrowth of turfgrass. The objectives of this study were to investigate the regrowth rate of zoysiagrass shoot under different mowing height for determination of proper mowing frequency. Recommended mowing interval were calculated by a rule that no more than 33% of the above ground height be removed in a single mowing. Daily shoot growth of zoysiagrass at 10 mm mowing height were 2.1~4.7 mm (July), 1.9~2.9 mm (August), 0.9~1.5 mm (September), and 0.6 mm (October). These results indicate that recommended mowing interval were 1.1~2.3 day for July, 1.7~2.4 day for August, 3.5~5.4 day for September, and 8.5 day for October, respectively. Daily shoot growth of zoysiagrass at 15 to 17 mm mowing height were 4.0~5.3 mm (July), 2.9~4.5 mm (August), 1.4~3.7 mm (September), and 1.3 mm (October). These results indicate that recommended mowing interval were 1.4~1.9 day for July, 1.7~2.5 day for August, 2.3~6.3 day for September, and 6.8 day for October, respectively. Daily shoot growth of zoysiagrass at 18 to 21 mm mowing height were 3.5~4.7 mm (July), 2.9~4.9 mm (August), and 1.5~1.8 mm (September). These results indicate that recommended mowing interval were 1.9~2.6 day for July, 1.8~3.1 day for August, and 5.9~7.0 day for September, respectively. Daily shoot growth of zoysiagrass at 50 mm mowing height were 4.6~4.9 mm (July), 5.0~6.5 mm (August), and 2.5~4.7 mm (September). These results indicate that recommended mowing interval were 5.1~5.4 day for July, 3.9~5.0 day for August, and 5.3~9.8 day for September, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.7-11
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• 1979

This study was attempted to establish the basic data for evaluating the processing suitability of Cynthia roretzi which is one of the most tasty sea foods in Korea. The results are as follows: The moisture content was increased from November to January. From this period to March, moisture was decreased and increased again from April. Protein content was high from August to November and lipid content was relatively high from June to February. From March to May the content of glycogen was 7.3 to 7.5 percent. From this period to February glycogen was decreased rapidly. By the results of condition index and chemical composition of Cynthia roretzi, the suitable harvest season as raw materials for processing seems to be from March to June.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.31-38
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• 1982

The water quality at the Nakdong River stream was surveyed for 3 years from 1978 to 1980 at quarterly intervals of January, April, June and October at 12 sites along the main stream from Sangju to Imhaejin and at 2 sites of Geumho and Nam River tributaries. The overall results are summarized as follows: 1) The levels of dissolved oxygen in the Geumho River tributary on the basis of three-year average were 0.7 ppm in January, 1.3 ppm in April, 4.0 ppm in July and 0.8 ppm in October. BOD concentrations in the same period were 91 ppm in January, 37 ppm in April, 6 ppm in July and 24 ppm in October. The water of Geumho River was so highly contaminated that the water seems to be unsuitable for any type of water use. 2) The relatively clean water in the upstream of the main Nakdong River was rapidly polluted by the highly contaminated water of Geumho tributary. That is, dissolved oxygen and BOD at Hwawon site right after junction of the tributary were 10.4, 8.8 ppm in January, 5.8, 6.5 ppm in April, 6.3, 3.2 ppm in July and 7.0, 5.3 ppm in October, respectively. The values of turbidity, ammoniacal nitrogen and electrical conductivity were also observed to be quite high.

• 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.